Ten Things I Like About... Podcast

This is a 10 minute, 10 episode podcast about unknown or misunderstood wildlife.

Listen on:

  • Apple Podcasts
  • Podbean App
  • Spotify
  • Amazon Music
  • iHeartRadio
  • PlayerFM
  • Podchaser
  • BoomPlay

Episodes

Coelacanth: Behavior

Wednesday Jul 05, 2023

Wednesday Jul 05, 2023

Summary: What are those coelacanth doing in the deep water of the ocean? Join Kiersten as she discusses some of the coelacanth’s behavior.
 
For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean.
 
Show Notes:
 Coelacanth, Smithsonian, https://ocean.si.edu/ocean-life/fish/coelacanth
“New Insights About the Behavioral Ecology of the Coelacanth Latimeria chalumnae Video Recorded in the Absence of Humans Off South Africa” by Jiro  Sakaue, Kazuhiko Maeda, Micheal J. Miller, Ryuichi Sakai, Koh-ichi Tahara, Hideki Abe, Kazuya Made, and Hitoshi Ida, Front. Mar. Sci., 10 November 2021, https://www.frontiersin.org
 
Music written and performed by Katherine Camp
Transcript
(Piano music plays)
Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.
(Piano music stops)
Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right out side our doors and some are continents away but all are fascinating. 
This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.
 
This episode continues coelacanths and the fourth thing I like about this enormous fish is their behavior.
Once again, I’m going to  state that we are still learning new things about the coelacanth everyday, so what I talk about in this episode is what we currently know, but the future may bring different information.
As I mentioned in the last episode, coelacanths are a deep water fish. They are typically found between 250 feet to1300 feet below the surface. We can see them using specialized scuba diving equipment called ‘rebreathers’ and by using submersibles. This technology has allowed us to study live individuals instead of the dead specimens that wash ashore or are, most often, caught as by-catch by fishermen. Because of this we know a lot about their anatomy, since many of the dead specimens have been dissected, but we don’t know as much about their behavior.
In the 1980’s studying coelacanths with deep sea vehicles became the common practice in the Comoros Island area. Between 1986 and 2009 we studied this population with submersibles and remote operated vehicles, or ROVs. Using their spot patterns we determined that this population contained approximately 300 to 400 individuals. We also observed their basic day to day pattern. 
A day in the life of a coelacanth consists of resting in caves at a depth of 500 feet to 800 feet during daylight hours. They will share caves with other coelacanths and smaller species of underwater life. The caves are carbonate caves formed during underwater volcanic eruptions. During the night, coelacanths leave the caves to hunt in even deeper waters. At least one individual was seen hunting in waters approximately 2000 feet deep. That’s a third of a mile under the surface of the water! I can’t even imagine the pressure these fish endure.
In the Fall of 2000, a few individuals were encountered by divers in another area near South Africa called Jesser Canyon. This encounter actually was the first direct contact between humans and a live coelacanth. We then began focusing on this area, as well, to study the coelacanth. Between 2002 and 2004 submersibles were used to watch this area. Here they observed 21 individuals in 16 different locations in canyons off the coast of Sodwana Bay, South Africa. These individuals were seen at depths of 300 feet to 450 feet. These studies revealed that the coelacanths in this area were traveling between two canyons, Jesser Canyon and Wright Canyon.
Research begun in 2018 wanted do something that had never been done before, study coelacanths without the influence or interference of humans. If you noticed in all the research I’ve detailed so far, the common thread was the presence of a submersible, human diver, or mobile ROV. We have no idea how these things might change the behavior of the coelacanths observed. We do know that the presence of unknown stimuli, meaning divers or ROVs, can alter the natural behavior of wild animals. 
These researchers used fixed cameras set up in a known coelacanth resting places to record the fish’s behavior without the presence of humans. They also wanted to record the ocean conditions such as temperature and current direction and velocity. To do this they placed two oceanographic recording devices near the study site. The main focus of this study was on the folding or unfolding of the first dorsal fin. 
Now you might think, wow that’s a lot of work to look at one trivial little fin,  but we’ve learned some of the most ground breaking things about animals by looking at one tiny little behavior, such as the eye movement of gorillas and the tongue flicking of snakes. This research actually shone a light on coelacanth behavior that we didn’t even know we should be looking for!
Okay, let’s take a moment to look at the iconic coelacanth image. If you haven’t yet googled the coelacanth, do so now and look at a few different photos of live coelacanths. Go ahead now, I’ll wait. Unless you’re listening to this podcast in your car. Do Not try to look up an image of the coelacanth if you are driving. Eyes on the road! 
For those of you able to safely pull up images, look at that first dorsal fin. What do you notice about it in 98% of the pictures? It’s unfolded and standing up right, correct? I’m actually looking at the cover of the book A Fish Caught in Time by Samantha Weinberg right now and the first dorsal fin is erect in the illustration of the coelacanth on the cover.
Up until the 2018 research project, we thought this was just how the coelacanth naturally carried this fin. Now we did know they were capable of folding it up and down and we assumed this fin was used for stabilization during swimming. We might have been wrong about that. According to the data collected in the absence of human interaction, the dorsal fin raises when the coelacanth encounters a stressor. 
In this research it was a sand tiger shark. They got great video of a coelacanth and a sand tiger shark in the same cave during the day. The shark showed no antagonistic behavior toward the coelacanth but while the shark was in the cave with the coelacanth, that first dorsal fin was raised. When the shark left the cave, the fin relaxed. They were other species of fish in the cave with the coelacanth as well and the fin was lowered while they were present. 
This sand tiger shark was larger than the coelacanth and might have posed a threat to the coelacanth. There isn’t any evidence that sand tiger sharks eat coelacanths but when you’re a potential prey item you’re not going to ask the shark if they going to eat you, you’re going to take action. Raising the dorsal fin may be a way for the coelacanth to look bigger and ward off predators. This type of behavior has been well documented in other species of fish.  
This observation floored me. It means that the presence of humans and ROVs is considered stressful to the coelacanth and our presence was probably changing the behaviors we observed. If we want to know more about them, we’re going to have to come up with some unobtrusive methods of observation. 
This research also studied temperature and currents near where the coelacanth were seen. Does this impact their behavior? It was observed that the coelacanth were present in the caves when the temperature of the water was between 59 degrees Fahrenheit and 71 degrees Fahrenheit. This has been seen in past research, as well. The researchers postulated that this is the optimal range for oxygen uptake in the coelacanth. The current direction was frequently southward and low in velocity when the coelacanths were seen at the study site, but more research will need to be done to determine if this is of any significance.
Wow! I don’t know about you but the coelacanth continues to amaze me. I’m glad you spent some time with me to learn about coelacanth behavior because it’s my fourth favorite thing about this ancient fish.
If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change. 
 
Join me next week for another episode about the coelacanth.  
 
(Piano Music plays) 
This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.

Coelacanth: Habitat

Wednesday Jun 28, 2023

Wednesday Jun 28, 2023

Summary: Where do coelacanths live? Join Kiersten as she talks about the habitat of the coelacanth.
 
For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean.
 
Show Notes: 
A Fish Caught in Time: The Search for the Coelacanth by Samantha Weinberg
“Madagascar may be a secret stronghold for ‘living fossil’ fish” by Stephanie Pappas, www.livescience.com
African Coelacanth, NOAA Fisheries, www.fisheries.noaa.gov
Coelacanth, Smithsonian, https://ocean.si.edu/ocean-life/fish/coelacanth
Music written and performed by Katherine Camp
 
Transcript
(Piano music plays)
Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.
(Piano music stops)
Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right out side our doors and some are continents away but all are fascinating. 
This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.
This episode continues the coelacanth and their habitat is the third thing I like about this amazing animal.
We are still learning more and more about the coelacanth everyday. And one of the things we’re still learning about is their habitat. Where exactly do these behemoths live? The information I’ll give you in this episode is what we know to date, but the future could show us something different.
When the coelacanth was discovered off the coast of South Africa eighty-five years ago we had no idea where it came from, but we did know where it was caught. The fisherman caught it off the coast of South Africa in the Indian Ocean at a depth of forty fathoms, or 240 feet. We didn’t see another one until 1952. This one was caught near the Comoros Islands which is off the southeastern coast of Africa in the Indian Ocean. Now we had an idea of where we might find more.
It wasn’t until later that researchers went to the islands and talked to the native islanders asking about this giant fish. (Quick note here, we should do more of this. Native inhabitants of areas that others explore know a lot about local wildlife. Why reinvent the wheel when you have so much information right in front of you, if you are just willing to listen?) Now, back to the coelacanth. Locals of the Comoros Islands were familiar with the coelacanth and had even eaten them in the past. Focusing on this area, several more coelacanth were found.
In 1998, more coelacanth were discovered in Indonesia, half a world away. The question was how did they get there? Did they migrate? Do they do that seasonally? Did a few get lost? Did they get washed away in a storm? Or have they been there this whole time?  Turns out, they’d been there the whole time.
When the Indonesian coelacanth was discovered, scientists performed DNA tests to see if they were related to the African coelacanth or possibly a new species. Once again these ancient fish surprised us, the two populations were indeed two separate species. According to research available at the recording of this episode it looks like these two species may have evolved separately.
The African coelacanth’s scientific name is Latimeria chalumnae and the Indonesian coelacanth’s scientific name is Latimeria menadoensis. I mention this because they were named after Marjorie Courtenay-Latimer the discoverer of the first specimen in 1938 and I think it’s wonderful that this woman of science gets props for her discovery. 
Before we get into where exactly these fish are found around the global let’s talk about at what depths they are found. This first specimen found in 1938 was caught by fisherman at a depth of 40 fathoms or 240 feet. For quite some time we thought this deepwater depth is where they lived.  But we now know that they actually inhabit, mesopelagic waters, also known as the “twilight zone”, that reach depths of 650 feet to 1,300 feet. That’s a lot deeper that we thought or ever expected. We’re not sure why the original specimens were caught in the shallower depths, but they could have been hunting or they could have been ill and unable to control their swim bladders properly and floated up into shallower depths. More recent sitings of both species have been between 300-500 feet deep, so obviously these fish are doing something important at these depths. Now that we know at what depths the coelacanth can be found let’s look at where in the world we can find them.
Let’s investigate the habitat of the African coelacanth, Latimeria chalumnae, first. These coelacanth are found in the Indian Ocean near the coasts of southeastern Africa, Madagascar, and the Comoros. The first one found in 1938 was caught off the coast of South Africa but after that no more were seen in the area. More specimens were found near the Comoros islands, that are situated between Madagascar and the east coast of Africa, in the 1950s so it was thought that the first one found in 1938 was a stray individual from the Comoros area. But when diving technology advanced, divers using “rebreathers” which allow to you dive deeper underwater than typical scuba gear, and later on researchers using submersibles, saw resident individuals in South African waters. Specimens have been caught off the coast of Madagascar  and off the coast of Mozambique and Kenya.
Latimeria menadoensis, also known as the Sulawesi coelacanth is from Indonesia. Two specimens were caught off the island of Manado Tua at the northeastern tip of Sulawesi. Later two more were sighted 225 miles southwest of this island. 
In both regions, coelacanth inhabit temperate waters near steep rocky slopes of volcanic islands. In the daytime, the Comoran coelacanths can be found clustered together in caves in submarine lava deposits. In the evenings they venture out to hunt. The two individuals observed from a submersible in Indonesia were seen in a deep carbonate cave at a depth of 500 feet. Both species seem to depend on caves, canyons, and cliff ledges for almost all aspects of their life. Sleeping during the day and hunting at night seem to be done in and around these structures. 
in 2021 researchers found evidence that Madagascar might be an unknown haven for coelacanths. In a new review of Madagascar fishery bycatch, 34 specimens were confirmed to be coelacanths. These catches have never been reported to scientists or conservationists before now. This indicates that coelacanth may be living off the coast of Madagascar. 
When we look at the history of this large island off the coast of Africa, it could be completely possible. Coelacanth are actually older than the island of Madagascar by about 330 million years, but Madagascar has had a coast line for around 88 million years; whereas, the Comoros Islands is only 15 million years old. Based on this history and recent bycatch reports, researchers think that Madagascar might be their ancestral home. More research will need to be done to find out if this is true, but it just one more thing that adds to the mystery of the coelacanth.
I am so glad you went deep sea diving with me today to learn about the habitat and species of the coelacanth because it’s my third favorite things about them.
If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change. 
 
Join me next week for another episode about the coelacanth.  
 
(Piano Music plays) 
This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.

Coelacanth: Anatomy

Wednesday Jun 21, 2023

Wednesday Jun 21, 2023

Summary: Join Kiersten as she takes you on a surprising journey from the head of the coelacanth to the tail. 
 
For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean.
 
Show Notes: 
A Fish Caught in Time: The Search for the Coelacanth by Samantha Weinberg
https://www.pbs.org/wgbh/nova/fish/anatomy.html
Music written and performed by Katherine Camp
 
Transcript
(Piano music plays)
Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.
(Piano music stops)
Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right out side our doors and some are continents away but all are fascinating. 
This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.
This episode continues the coelacanth and their anatomy is the second thing I like about this ancient animal.
In the first episode we established that the coelacanth is a fish, so the anatomy should be like fish anatomy, right? Maybe, but this fish has been around for 400 million years and from comparisons between living specimens and fossils, they don’t seem to have changed much at all. So the coelacanth has some anatomical surprises that other fish do not possess.
Let’s start at the head of the coelacanth and work our way back. In the center of the snout there is a large jelly-filled cavity. It’s called the rostral organ. Scientists initially thought this might be an electrosensory organ for detecting weak electrical impulses given off by prey. This hypothesis was supported by examining the organ’s intricacies including nerves and how it interacted with the brainstem. When submersible exploration became available to scientists, we were able to test this on a living coelacanth. Using electrical fields, researchers confirmed that coelacanths do indeed respond to electrical fields under water. There is no other vertebrate, that we know of, alive today that has a rostral organ. So we’re already off to an interesting start. Let’s see what else the coelacanth has that other animals may not!
Moving to the mouth we find teeth. That’s not entirely unique in fish that eat other fish and the coelacanth is a carnivore. They have three different shapes of teeth, one is a high, sharp cone-shaped tooth that could be called a fang, the second is a midsized, sharp cone-shaped tooth, and the last is a small rounded tooth.  What is unique to the coelacanth is that the small rounded teeth are embedded in a bony dental plate that lies beneath their chin. We’re not entirely sure what the advantage of having a dental plate gives the coelacanth. In general, the teeth seem more like a way to keep fish in the mouth once they are sucked in versus tearing or chomping on their prey.
The eyes are just above the mouth and they are attached to thick optic nerves. The eyes are large. I’d say they are in proportion to their body and they are a five foot long fish, so…large eyes. Each eye does have a few cones, which allows for color vision, but they many rods, which help detect light. This is perfect for the coelacanth because they live deep under water where there is very little light available. The rods help them see in almost near darkness.  
They also have something else that helps them see in the dark and this is a layer behind the retina of the eye called the tapetum lucidum. If you’ve ever seen light flash in your cat’s eyes at night, you’re seeing the tapetum lucidum. This layer acts like a mirror reflecting the light that comes into the eyes back out of the eye to increase the amount of light that passes over the retina. This enhances the coelacanth’s ability to see in low light.
Just behind the eye toward the top of the head is the intracranial joint. Until we rediscovered the coelacanth this joint had only been seen in fossils of primitive fish. This joint allows the coelacanth to open its mouth exceptionally wide to swallow fish and other prey. Two powerful muscles cross the intracranial joint providing strength to the coelacanth’s jaws. The coelacanth is the only fish alive that still has an intracranial joint. 
Just under this joint and near the eye is the brain. The brain is small. It takes up only 1.5% of the brain case in mature adults. In a 90 lbs coelacanth the brain weighs less than a tenth of an ounce. That’s a pretty tiny brain. There is no extant vertebrate with this much of a difference between the size of the brain and the size of the body. Although, they have been alive for 400 million years so it must be working. 
Coelacanths do have gills like other species of living fish and they are located behind the eye in the usual place that you find fish gills. They are relatively small in comparison to the overall body size, but they are similar to other fish species found at the same depth as the coelacanth. The relatively small surface area of the lungs is indicative of a slow-moving fish as opposed to an active fish. All the evidence we have to date does show that the coelacanth is a relatively slow-moving fish. When you’re a five foot long fish, you take your time getting places.
This large fish is covered in scales and those scales are woven tightly together like armor. I think that seems appropriate for such an ancient animal. The scales are hard and rough to the touch. Each scale has tiny, tooth-like spikes called denticles all over the surface which creates the roughness. The hard scales and denticles provide protection against predators and rocks. The scales are a beautiful steely-blue color with random white spots throughout. The pattern of the spots is unique to each individual and scientists have used that to their advantage. Researchers use the spots like name tags to identify individual coelacanth.
The fins of this fish are quite spectacular. They have six fins that are lobed and this puts them into a group of fish known as the lobed-finned fish. Lungfish and coelacanth are both included in this group.  What’s the difference between a lobed fin and a normal fin? Great question! Lobed fins are fins that are attached to stalks that project out from the body rather than fins that are attached directly to the body. They look kind of like paddles sticking out from the side on the animal. The coelacanth has six lobed fins, one on each side just behind the gills called pectoral fins (2), one on each side of the pelvis called pelvic fins (4), one small secondary dorsal fin on the top of the body (5), and one anal fin on the underside of the body before the tail (6). 
Overall the coelacanth has seven fins, not including the tail. The first dorsal fin is the only non-lobed fin. It’s larger than the other fins and attaches directly to the body. It can be raised and lowered to change its surface area.
We call the coelacanth a vertebrate because it has an internal skeleton which usually implies that it has vertebrae or bones of the spine. Once again the coelacanth surprises us. They have a notochord in place of a bony spine. A notochord is a thick-walled, fibrous, and elastic tube that is filled with oil. This is what the coelacanth has in place of a bony spine. Most creatures with a backbone replace the notochord with vertebrae in the embryonic stage. But adult coelacanth use the notochord for their longitudinal support.
Like almost all other fish species,  the coelacanth has a swim bladder. Fish use the swim bladder to maintain buoyancy in the water. Most fish use air to inflate the swim bladder and they are able to modify the amount of air depending on the depth in which they wish to swim. I bet you didn’t see this coming but…, the coelacanth’s swim bladder is not filled with air! Okay, maybe you did see that coming. The coelacanth’ s swim bladder is filled with oil and fat, but it works the same as the air filled bladder, helping maintain buoyancy. 
That brings us to the end of the fish, also known as, the tail. Hopefully, you’ve listened to the first episode of this series where I talk about the rediscovery of the coelacanth, if not definitely check it out. When Marjorie Courtenay-Latimer rediscovered the coelacanth in 1938, she described the tail as looking like a “puppy dog tail.” The tail is actually divided into three sections with a small tail fin in the middle. The tail is flat and powerful giving the coelacanth the ability to dart forward forcefully when catching prey or escaping predators. The tail can rotate and flex from side to side and is thought to help the fish with trim and balance.
That is all I have for coelacanth anatomy. Thanks for joining me on this head to tail adventure because it’s my second favorite thing about the coelacanth.  
 
If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change. 
 
Join me next week for another episode about the coelacanth.  
 
(Piano Music plays) 
This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.

Coelacanth: Rediscovered

Wednesday Jun 14, 2023

Wednesday Jun 14, 2023

Summary: In 1938 something amazing happened in a small town off the eastern coast of South Africa. Join Kiersten as she reveals the unbelievable story of how the coelacanth, a fish thought extinct for millions of years, was rediscovered. 
For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean.
 
Shoe Notes: 
A Fish Caught in Time: The Search for the Coelacanth by Samantha Weinberg
Music written and performed by Katherine Camp
 
Transcript
(Piano music plays)
Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.
(Piano music stops)
Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right out side our doors and some are continents away but all are fascinating. 
This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.
This episode begins a new series about an animal thought to have been extinct since the time of the dinosaurs, but as this episode will show the coelacanth has been here all along and this is the first thing I like about them.
We’ll begin with the unbelievable story of the rediscovery of this amazing animal.
Let me set the scene for you: It’s 1938 in the town of East London, South Africa. East London sits on the eastern coast of South Africa and harbors a bustling fishing industry. It’s a hot and humid December day and the young, female curator of the East London Museum is hustling to get her newest exhibition completed before they close for the upcoming Christmas holiday. As Marjorie Courtenay-Latimer is painstakingly assembling a rare dinosaur fossil, a startling sound shatters the peace of the museum and her concentration. It’s the ringing of the newly installed phone and she doesn’t know it yet, but it’s the sound of destiny calling. 
On the other end of the phone is the manager of the Irvin and Johnson trawler fleet. Mr. Jackson would call Marjorie when his ships came back to port with specimens that she might be interested in for the museum. This day Majorie was so stressed to get things organized before the holiday break that she almost said No, but she didn’t want to jeopardize her relationship with the shipping company manager. She decided to take a quick break and see what she could see.
She had no idea what she’d find when she stepped onto the deck of the Nerine. Over the phone Mr. Jackson had indicated that several pounds of sharks were available for her perusal. The museum didn’t need any sharks currently and Marjorie had decided that she’d most likely not take anything, but she took a look through the pile of fish on the forecastle deck anyway. She found sharks, seaweed, starfish, sponges, rat-tail fish, and many more. She carefully sorted through the pile but saw nothing she of interest which strengthened her reserve to take nothing that day. 
About halfway through she noticed a blue fin, not the usual faire, and she dug down through slime and scales to take a closer look. What she’d found was a fish, a very unusual fish.
A quote from the book A Fish Caught in Time: The Search for the Coelacanth by Samantha Weinberg expresses the discovery in Marjorie’s own words.
“I picked away the layers of slime to reveal the most beautiful fish I had ever seen,” she recounts. “It was five feet long, a pale, mauvy blue with faint flecks of whitish spots; it had an iridescent silver-blue-green sheen all over it. It was covered in hard scales, and it had four limb-like fins and a strange little puppy dog tail. It was such a beautiful fish - more like a big china ornament - but I didn’t know what it was.” End quote.
The fisherman who stood by watching, said in thirty years of fishing he’d never seen anything thing like it. They’d caught it at a depth of forty  fathoms, 240 feet, off the mouth of the Chalumna River. When the captain of the ship first saw the catch he’d thought it so beautiful he’d almost set it free. Marjorie’s gut told her to take it. 
She and her museum assistant, Enoch, wrapped the fish in a bag and transported it back to the museum to give it a more complete inspection. It was weighed and measured and Marjorie sketched a rough picture of this puzzling fish. The specimen weighed in at 127 pounds and a voice in Marjorie’s head kept circling back to something she’d learned as a child in grade school. She’d gotten in a bit of trouble with her teacher and had to write a sentence as punishment.
‘A ganoid fish is a fossil fish.’ She had to write it twenty-five times and; therefore, never forgot the statement. Essentially it means a ganoid fish is a fish that has long been extinct and is only seen in the fossil records. (As an aside, Ganoid also refers to a type of scale that can be found in extant fishes such as bowfin, gars, paddlefish, and sturgeon.) This sentence kept running through her head as she examined the fish in front of her, but logically it could not be a ganoid fish because this was a fresh specimen caught just that morning. 
She looked through all the books she had on fish but nothing matched. She decided she must preserve the fish for future examination by someone with a bit more knowledge than herself. Preserving a five foot, 127 pound fish was not something that could be done in the museum, so she had to come up with some alternate plans. First she asked the mortuary if they’d place it in one of their lockers, since the were refrigerated. The mortician balked at storing a giant fish with the bodies of the human dead, he was worried what the town might think. Then she thought of the food storage building. It also hade refrigeration, but that was also a no go. 
Her final option was the taxidermist and he was certainly up for the challenge. Between the two of them they wrapped the humongous fish in formalin soaked towels and stored it in the taxidermist’s store. Next, Marjorie sent a letter to James Leonard Brierley Smith, a chemist lecturer at Rhodes University in Makhanda, South Africa. J.L.B. Smith was an amateur ichthyologist and acted as the honorary curator of fishes for the smaller museums along the south coast, such as the East London Museum. She asked for his help in identifying a strange fish she’d found and sent along her sketch of said fish. 
Because of the holiday, his response was delayed several days. As she waited, Marjorie checked in on her find daily. Despite all their hard work the fish was inevitably deteriorating. The taxidermist had to get to work at his trade to save any portion of the fish. Finally, an answer came back from JLB Smith. It was most likely a coelacanth. Marjorie was gobsmacked. The coelacanth was a fish thought to have gone extinct during the time of the dinosaurs. They hadn’t existed outside of a fossil for 65 million years, or so we thought. Marjorie Courtenay-Latimer’s discovery shook the scientific community.  
I hope this episode whet your appetite to learn more about the coelacanth because their rediscovery is my first favorite thing about these forgotten fish.
If you’d like to know more about Marjorie Courtenay-Latimer and the rediscovery of the coelacanth, I highly recommend the book A Fish Caught in Time: The Search for the Coelacanth by Samantha Weinberg. It is one of my favorite non-fiction reads. 
 
If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change. 
 
Join me next week for another episode about the coelacanth.  
 
(Piano Music plays) 
This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.

Caecilians: Conservation

Wednesday May 31, 2023

Wednesday May 31, 2023

Summary: Even though we don’t know much about caecilians they still need our help. Join Kiersten as she talks about what threats caecilians face and how we can help.
 
For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean.
 
Show Notes: 
IUCN Red List: www.iucnredlist.org
“Fatal fungus found in third major amphibian group, caecilians,” by Natural History Museum, Phys Org; phys.org/news/2013-05-fatal-fungus-major-amphibian-group.html
Chytridiomycosis: Cornell Wildlife Health Lab: cwhl.vet.cornell.edu
Conservation Organizations:
IUCN SSC Amphibian Specialist Group: www.iucn-amphibians.org
Amphibian Ark: www.amphibianark.org
Save the Frogs: savethefrogs.com
Association of Zoos and Aquariums: www.aza.org/amphibian-conservation
 
Music written and performed by Katherine Camp
 
Transcript
(Piano music plays)
Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.
(Piano music stops)
Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right out side our doors and some are continents away but all are fascinating. 
This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.
This episode concludes caecilians and the tenth thing I like about these intriguing creatures is the conservation efforts we already have under way to protect their future. 
Throughout the last nine episodes I have clearly established that we don’t know as much about these fascinating amphibians as we should considering how long they’ve been on the planet. Of course, they are fairly secretive living underground and under the water, so it’s definitely been hard to study them. Having said this, you may be wondering how do we know anything about their conservation status if we can’t get an accurate count of how many are in the wild. The answer is, we can’t, but we do have enough information on some of the species to classify them on the IUCN red list of threatened species.
As a reminder, or for the first time if you haven’t listened to any of my previous series’, the IUCN stands for International Union for Conservation of Nature and Natural Resources. They list the conservation status of animals and plants from around the world. A species can be listed as data deficient, which means we don’t have enough information to make a decision on whether the population is so low that the species is in danger of disappearing, or extinct, which means all the individuals of that species have died. They no longer exist. 
There are several stages in-between data deficient and extinct. These classifications help us develop plans to help species survive the changing environment that is most often impacted by human activity.
Of the 200 species of caecilians that we know about, 193 are listed on the IUCN’s red list. 76 are listed as Least Concern which is good, that means their populations are healthy and thriving. 3 are listed as Near Threatened which is a step up from Least Concern, which means they are still okay for now but we should start including them in conservation plans. 7 are listed as Vulnerable which means they are one step away from Endangered and need help now. 16 are listed as endangered which means if efforts are not taken now we could lose this species. And 2 are listed as critically endangered which means they are a step away from extinction. That leaves 89 listed species as Data Deficient, almost half of the known species of caecilians.
Now that we have the numbers, we have to ask what is impacting caecilian populations. I think you, my listeners, may be able to guess. According to the IUCN website habitat loss is the biggest impact on caecilian populations. It’s the subtropical and tropical species that are being disturbed the most and the activities that are impacting them are all human centric activities. Non-timber agriculture is the largest pressure on the habitat in which our most endangered caecilians are found. The pesticides used in association with the agriculture is the next threat to their lives. Since they live in the ground and are dependent on mainly insects for food you can see how they would be majorly impacted by these activities.
So what exactly are we doing to help? The first thing is we’re still studying them. The more information we have about how they live and where they live the better our conservation plans. We have to know what habitat is best for them, what they eat, and how long they live to truly understand how to successfully protect them. Studying their natural history is a great tool for any conservation efforts for their future. Any students or zoologists out there listening that are looking for a species to study, maybe you can think about caecilians.
Studying animal’s in situ, which means out in their natural habitat, can be difficult. First you need to find them, then you need to catch them without harming them, then you measure everything you can possibly measure such as weight, length, color, sex, and any distinguishing characteristics such as scars or patterning. Then before you let them go you tag them with some kind of ID tag that does not harm they, so if they are captured again or seen by naturalists data can be added to their history. For example, when ornithologists catch birds they place a ring around their leg that has a number on it specific to that bird. When that bird is found again or birders report seeing the bird that information is added to their file. This helps us understand how large an animal’s home territory my be, determine migration paths, and can tell us how long they live. 
Caecilians are even more difficult than most because they choose to live underground or underwater making it terribly difficult to find them, and once they have been found we have no way of permanently tagging them. This is something scientists are still working on for further research.
The other thing we are doing is protecting their habitat by declaring swaths of land preserves or national parks. This is often done because other plants and animals in the same area need protection, too. It’s a great side effect for the caecilians.
Habitat loss is not the only thing caecilians need to worry about. Disease is another serious threat to amphibians. One of the worst diseases effecting amphibians is chytridiomycosis. This is an infectious disease caused by a fungus and has been the cause of declines or complete extinction of over 200 amphibian species. It is know to effect over 350 species of amphibians and until 2013 we thought caecilians might be safe. Chytrid fungus gets into the skin of the amphibian which is devastating because amphibians breathe and take up water through their skin. This fungus interferes with that function. An infection is almost always fatal. Because most caecilians are fossorial we had hoped they might be unaffected by chytrid but a study published in 2013 did find the fungus present in 50% of the individuals tested from the wild. This was devastating news.
For years scientists have been working on a cure for the fungus, but very little head way has been made since what kills the fungus often kills the amphibian. Putting anything in on amphibians skin is instantly absorbed into their system, so it’s a thin line between curing and killing. Some head way has been made with an ionic liquid spread on the backs of frogs but this can only be done with captive individuals and is still not 100%. To date we have no real cure for this disease. 
So what can we do to help? If you are a hiker or explorer in areas where amphibians are common, the chytrid fungus is probably found there. To prevent spread of the fungus, disinfect your clothing and gear before you use them again at another site and do not transport amphibians of any kind from one habitat to another.  
On that note, if you are a hobbyist that likes to have amphibians as household pets, including caecilians, be sure you’re not getting your animals from illegal harvesting companies. Trapping for pet trade in another reason our amazing amphibians, including our caecilians, are disappearing. Make sure you’re patronizing a responsible person who sells only animals born in captivity.
For more on what you can do to help caecilians and other amphibians in the wild, check out my show notes where I have a few great organizations listed.
That’s it for caecilians! Thank you for joining me on this journey through caecilian behavior. I know I had an amazing trip and I think you did too. Conservation efforts for caecilians is my tenth favorite thing about this mysterious amphibian. 
 
If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change. 
 
Join me in two weeks when we’ll talk about an animal thought extinct since the time of the dinosaurs until it was rediscovered alive and well in 1938! 
 
(Piano Music plays) 
This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.

Caecilians: Odds and Ends

Wednesday May 24, 2023

Wednesday May 24, 2023

Summary: In this episode Kiersten and a guest host talk about a few things we know only a little bit about, such as caecilian origins and how they communicate.
 
For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean.
 
Show Notes: 
Caecilians: An Overview https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/caecilians
 
“Petrified Forest Brings the Funk with the World’s Oldest Fossil Caecilian.” Park Paleontology News, Vol 15, No 1, Spring 2023. Https://www.nps.gov/aticles/000/petrified-forest-brings-the-funk-with-the-world-s-oldest-fossil-caecilian.htm
Music written and performed by Katherine Camp
Transcript
(Piano music plays)
Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.
(Piano music stops)
Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right out side our doors and some are continents away but all are fascinating. 
This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.
This episode continues caecilians and the ninth thing I like about them is a bit of this and a bit of that. In this episode we’re going to talk about some of the amazing things that we only know a little bit about and my husband Georgiy will be joining me.
Hello Georgiy!
Georgiy: Hello!
Kiersten: Are you enjoying my series on caecilians?
Georgiy: Da!
Kiersten: I’m so surprised about all the amazing attributes these animals have. I think it’s my favorite research so far!
Georgiy: I’m surprised that they have lived for so long and we hardly know anything about them!
Kiersten: I agree and speaking of which. New information about their fossil history has recently been discovered!
Georgiy: Really?
Kiersten: Yes! In the Chinle Formation of the Petrified Forest National Park in Arizona, paleontologists have found the oldest caecilian fossils to date.
Georgiy: How old are they?
Kiersten: They are 220 million years old. More than 80 bones from the caecilian named Funcusvermis gilmorei have been found. Scientists are excited about this because it bumps the fossil record of caecilians back about 35 million years. So they are even older than we thought they were. These ancient caecilians have the two rows of teeth like modern day living caecilians but, unlike extant caecilians, they have legs and no tentacles. Finding these fossils answers a question that scientists have had for many years. Where are the Triassic Era caecilians? Now we know!
Georgiy: Does this tell us anything new about modern day caecilians?
Kiersten: Sort of. These fossils help support the hypothesis that living amphibians are more closely related to each other than any of their extinct ancestors. So frogs, salamanders, and caecilians that are alive today are more closely related to each other than their long dead ancestors. Even though modern day amphibians look and act so much different from each other.
Georgiy: That’s interesting.
Kiersten: I think so, too. You know what else is interesting?
Georgiy: What?
Kiersten: Caecilians are both terrestrial and aquatic.
Georgiy: I say again, What?
Kiersten: (laughs) I’ve mentioned this before in a few episodes but I wanted to make it very clear. Some caecilians live on land, terrestrial, and some live underwater, aquatic. The terrestrial species usually live under ground in tunnels, but some live in the thick leaf liter of the tropical forest floor.
Georgiy: Oh…I see. 
Kiersten: Good. Now to throw another curve at you, some species of caecilians live on land as adults but live under water as juveniles.
Georgiy: Whoa! How does that work?
Kiersten: As adults, some caecilian species lay eggs in an underground burrow near fresh water. When the eggs hatch the young make their way to the water where they slither in and spend their larval stage under the water.
Georgiy: How can they breathe?
Kiersten: Oh, good question! While in the egg the young developed external gills to help them breath under water. They also developed lungs so, when they become adults they loose the gills and emerge onto land where they breath air with their lungs. 
Georgiy: That’s just cool! So let me get this straight, some caecilians live their entire lives underground, some spend their entire lives underwater, and some split their lives between the water and the ground.
Kiersten: Exactly! 
Georgiy: This episode has been pretty cool.
Kiersten: But wait, there’s more! Another interesting thing about caecilians is how they communicate. 
Georgiy: Oooo! How do they communicate?
Kiersten: With chemical perception. 
Georgiy: Explain please.
Kiersten: Why certainly. Caecilians are the only amphibians with tentacles. These tentacles are on their face in-between their eyes and nose and detect chemical in the environment. Scientists believe that they also use these to communicate with each other. 
Georgiy: Do they talk to each other a lot?
Kiersten: Most caecilians appear to be solitary, so probably not, but we don’t know much about their social lives. The aquatic caecilian Typhlonectes natans uses chemical cues to find mates. They probably use their tentacles to sense pheromones. It’s highly possible that the terrestrial caecilians do the same thing. 
Georgiy: So they sniff out a good mate.
Kiersten: (laughs) Yes! There is something to be said about a nice cologne.
Well thanks for helping me out today, Georgiy.
Georgiy: You’re welcome.
Kiersten: That all I’ve got for this odds and ends episode. Thanks for joining me for this second to last episode about a little bit of this and a little bit of that about caecilians because it is my ninth favorite thing about them!
 
I would like to take a moment to thank a gentleman at Central Arizona College in Apache Junction, Arizona who went to great lengths to help me find information on the caecilian when I began this series. Thanks Richard, you’re the man!
If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change. 
 
Join me next week for the final thing I like about caecilians!
 
(Piano Music plays) 
This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.

Caecilians: Defense

Wednesday May 17, 2023

Wednesday May 17, 2023

Summary: Join Kiersten as she talks about how caecilians defend themselves against predators.
 
For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean.
 
Show Notes: 
“Morphological Evidence for an Oral Venom System in Caecilian Amphibians,” by Pedro Luis Mailho-Fontana, Marta Maria Antoniazzi, Cesar Alenandre, Daniel Carvalho Pimenta, Juliana Mozer Sciani, Edmund D. Brodie Jr., and Carlos Jared. iScience, Volume 23. Issue 7,101234, July 2020. https://doi.org/10.1016/j.isci.2020.101234
 
“Predation on Caecilians (Caecilia orientalis) by Hawks (Leucopternis princeps) Depends on Rainfall,” by Harold F. Greeney, Rudy A. Gelis, and W. Chris Funk. Herpetological Review, 2008, 39(2), 162-164. 
 
“Skin gland concentrations adapted to different evolutionary pressures in the head and posterior regions of the caecilian Siphonops annulatus,” by Carlos Jared, Pedro Luis Mailho-Fontana, Rafael Marquez-Porto, Juliana Mozer Sciani, Daniel Carvalho Pimenta, Edmund D. Brodie Jr., and Marta Maria Antoniazzi. Scientific Reports 8, Article number: 3576 (2018).
 
“This Worm-Like Amphibian May Pack a Venomous Bite,” by Alex Fox, Smithsonian Magazine, https://www.smithsonianmag.com/smart-news/worm-amphibian-may-pack-venomous-bite-180975266/
Music written and performed by Katherine Camp
 
Transcript
(Piano music plays)
Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.
(Piano music stops)
Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right out side our doors and some are continents away but all are fascinating. 
This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.
This episode continues caecilians and the eighth thing I like about these amazing amphibians is how they defend themselves.
Who are caecilians protecting themselves from? We’re aware of a few species of animals that eat caecilians. Snakes, spiders, turtles, and ants have all been reported preying on caecilians. In 2008 a surprising animal was added to this list. A group of researchers watching cameras set up to record a Barred hawk nesting site in Ecuador captured something unexpected. The parents fed their single chick many different animals including 50 individual Caecilia orientalis, a terrestrial caecilian species. Researchers are unsure how a hawk was able to find a subterranean animal easily enough to bring 50 of them to their young, but we can add these hawks to the list of caecilian predators.
So how do caecilians protect themselves from getting eaten? The first way caecilians protect themselves from predators is really a bit of a happy accident and that’s their fossorial lifestyle. Spending most of your life underground does cut down on the number of predators that can find you, although it doesn’t seem to be slowing down the Barred Hawk. Even so, evolution has given terrestrial caecilians a bit of a jump start on protecting themselves by equipping them to live underground. Aquatic caecilians spend a large amount of time close to the substrate of their chosen water source and hidden in dense plant matter, also a great place to start protecting themselves.
Caecilians do have a few other tricks up their sleeves to actively defend themselves from predators. 
But before we get to those, I want to tell you that most of the information I’ve found on this subject comes from the study of one species of caecilian, Siphonops annulatus, so it may not apply to all species of caecilians. One more I caveat need to mention is that this information is based on educated inference. Because we have not actively seen caecilians defending themselves from predators, we are making some assumptions based on the natural history of other species of animals.
Now that’s out of the way, let’s get to the really cool stuff!
Most amphibians are covered in mucus to help with oxygen transmission and disease protection, caecilians are no exception. Actually, caecilians have more mucus glands than any other amphibian. If you remember, in the locomotion episode, I mentioned that some fossorial caecilians, such as Siphonops annulatus, use their mucus to help lubricate their tunnels to make movement easier. To do this they have glands on their heads that create and release the mucus. They also have glands on their rear end and scientists assumed it was for the same reason. Not so. The gland on the rear end expels a poisonous mucus. We assume that this poison is excreted to protect them from predators that might follow them into their tunnels. 
They also tend to plug the opening of their tunnels with their rounded bums when they are sleeping or resting. A perfect way to keep a predator at bay, greet them with a face full of poison!  
Another option Siphonops annulatus has is their bite. A recent study from 2020 has shown that Siphonops annulatus may have a venomous bite! Once again this is a first for an amphibian. It’s not the first time toxins have been found in Order Amphibia. The most famous example is poison arrow dart frogs that produce poison that is excreted onto their skin. Now, they are classified as poisonous because the toxin is transferred through touch. Animals classified as venomous such as rattlesnakes and Gila monsters inject their toxin into another animal through something like fangs or teeth. Up until this recent discovery, we thought there were no venomous amphibians. 
The study found glands closely associated with this caecilian’s teeth. They found the glands in both the upper and lower jaws. These glands are the same type of glands found in certain venomous reptiles. Within the glands researchers found a combination of mucus, lipids, and proteins. The researchers isolated the cells found in the glands and discovered a similarity to oral venom glands identified in the Texas alligator lizard. As of the recording of this podcast the Texas Alligator lizard and Siphonops annulatus are not classified as venomous, but we’ll have to wait to see what future research determines.
Unlike snake venom glands there appear to be no muscles related to the glands in Siphonops annulatus to facilitate injection of poison, but the caecilian teeth are covered in mucus produced by these oral glands. This leads the scientists to believe that the venom may be secreted when the caecilian clamps it jaws down tightly on a prey item.
There needs to be more study to determine whether this substance is a toxin used to immobilize prey and if it is truly a venomous substance at all. Another purpose for this adaptation may also be as a defense against predators. Considering we’ve never seen defensive behavior in Siphonops annulatus in situ, these glands might be related to protection against predators. 
These scientists did find oral glands present in other species of terrestrial caecilians meaning that they all may have venom that they use for capturing prey and for defense. Further research needs to be done to confirm or debunk this. When they looked at some aquatic caecilians they found no oral glands, which truly intrigues researchers. 
That is all we currently know about how caecilians protect themselves from predation, but I’m sure future research will turn up even more amazing information, and I can’t wait to read about those discoveries because defense is my eighth favorite thing about caecilians. 
 
I want to take a moment to say hello to a young listener. Lydia, thanks for listening and I’m so glad you’re enjoying the podcast. Speaking of which…
If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change. 
 
Join me next week for another thing I like about caecilians!
 
(Piano Music plays) 
This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.

Caecilians: Reproduction

Wednesday May 10, 2023

Wednesday May 10, 2023

Summary: Now that we know about the existence of caecilians. Let’s talk about how caecilians make more caecilians! Join Kiersten as she walks us through the various ways caecilians reproduce.
 
For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean.
 
Show Notes:
“The Care and Captive Breeding of the Caecilian Typhlonectes natans” by Richard Parkinson. Herpetological Bulletin, 2004, Number 88.
 
“Reproductive ecology of female caecilian amphibians (genus Ichthyophis): a baseline study” by Alexander Kupfer, Jarujin Nabhitabhata, Werner Himstedt. Boiological Journal of the Linnean Society, Vol 83, Issue 2, October 2004, pg 207-217.
*cool egg pictures in this paper
“Life history and reproduction of the neotropical caecilian Siphonops annulatus with special emphasis on parental care” by Carlos Jared, Pedro Luiz Mailho-Fontana, Simone G. S. Jared, Alexander Kupfer, Jacques Hubert Charles Delabie, Mark Wilkinson, and Marta Maria Antoniazzi. Acta Zoological, Vol 100, Issue 3, pg 292-302.
 
  Music written and performed by Katherine Camp
 
Transcript
(Piano music plays)
Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.
(Piano music stops)
Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right out side our doors and some are continents away but all are fascinating. 
This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.
This episode continues caecilians and the seventh thing I like about these hidden gems is how they reproduce.
When it comes to reproduction most animals will reproduce in one of three ways. If you are viviparous, you give live birth to young that have developed in your uterus. If you are ovoviviparous, you give live birth to young that have developed inside eggs that are incubated in your uterus. These young are typically born with a yolk that helps nourish the young for a few days after birth. If you are oviparous, then you lay eggs that are incubated outside the body by parental warm or substrate covering. There are animals out there that reproduce in other ways, but these are the three main ways of animal reproduction.
Caecilians use two of these reproductive techniques. Of the caecilians we know of today, they are either oviparous or viviparous. 
Let’s take a look at our oviparous species’ first. Some research has been done on species in Family Ichthyophiidae. These species lay eggs and their young go through an aquatic larval stage. The species studied in this particular research was found in Thailand and individuals were observed in the wild as well as in captivity.  It was actually one of the first times caecilians in this family had been studied in situ, which means on site in their natural habitat. Ichthyophis kohtaoensis was studied for three consecutive years and researchers discovered many previously unknown behaviors. 
When we talk about reproduction in most species, it tends to revolve around certain times of the year. Very few animals are like humans and reproduce anytime of the year. Most amphibians found in tropical areas jump into breeding mode at the start of monsoon season, so one of the first questions researchers asked is whether this would be the same for caecilians. The answer they found was a bit of yes and a bit of no. Just like other amphibians, caecilians breeding season was cyclical and revolved around the rainy season. But actual mating appeared to begin at the end of the dry season before the rains came and continued into the beginning of the rainy season. Egg laying typically happened after the rainy season had already begun.
When it comes to parental care, if there is any given, it is the female only. Ichthyophis kohtaoensis does incubate eggs for approximately three months. Toward the end of the dry season, females will begin to gain weight in anticipation of remaining in a nest to guard and incubate eggs. The average number of eggs is 37 with a range of 22-58 eggs laid in one nest. Larger females tended to have larger clutch sizes. The eggs are round and clear, so you can see the developmental stages of the young inside. The pictures they included in their  scientific paper were pretty cool!
The nest site is extremely important because the larval stage of this caecilian is spent in the water. Females will chose a site with softer substrate such as sand, loose soil beneath tree roots, and sandy clay loam under grass tufts. Every nest found was between seven to nine feet from the edge of a freshwater source. The sources were varied including standing ponds and pools, slow moving brooks and rivers, and large seasonal ponds. Once the eggs hatch the young make their way into the water and are on their own. Field studies and captive observations indicate a long larval period so the chosen body of water needs to last long enough for the young to survive through this period to adulthood.
This pattern of reproduction is only one option for oviparous species. Another pattern lengthens the parental care window and has been well studied n only one species, Siphonops annulatus. Unlike Ichthyophis kohtaoensis, the young of Siphonops annulatus do not have an aquatic larval stage. When the young of this caecilian hatch they remain in the underground nest with the mother. 
Breeding season occurs about about the same time as our previous caecilian, beginning at the end of the dry season. Females gain weight at this time and lay eggs after the rainy season has begun. This is more support for the hypothesis that caecilian reproduction is cyclical and follows the seasonal changes revolving around monsoon season because this pattern has now been seen in two species from different countries. Ichthyophis kohtaoensis is found in India and Siphonops annulatus is found in Brazil. The observations reported in the study on Siphonops annulatus were collected over a period of ten years and were gathered in situ and in captivity. 
The young of Siphonops annulatus hatch after about a month but remain in the underground nest with the mother for approximately four months. This species practices dermatophagy which means they eat skin. Specifically the young eat the outer layer of their mother’s skin. Part of the weight that the female gains before egg laying includes a thickening of the outer layer of her skin. This layer bulks up with nutritious fatty lipids that the young scrape off using special baby teeth that they lose when they leave the nest. 
In captivity, young have also been seen congregating around the mother’s cloaca, which is the orifice near the end of the tail, consuming a liquid. We don’t currently know what this substance is but it may be another nutritious liquid for the young. After four months of feeding on mom in the nest, the young will emerge into the world and be on their own. Siphonops annulatus lay fewer eggs than Ichthyophis kohtaoensis and this may be due to the intensive parental care Siphonops annulatus provides.
The last form of reproduction in caecilians is live birth and we’re going to look at one of the most well studied species of viviparous caecilians, Typhlonectes natans. Hopefully you remember from previous episodes that this species is an aquatic caecilian, living their entire lives in the water. The information about the breeding behaviors of this species comes mostly from captive specimens, so this information needs to be taken with a little grain of salt because animals always act a little different in captivity than they would in the wild. These behaviors have been in several different individuals; therefore, we feel fairly comfortable saying this is what happens in the wild. 
Once again, it appears that breeding behaviors are influenced by monsoon season, but in a slightly different way than with our egg-laying species. The dry season that comes before monsoon season is when Typhlonectes natans is triggered to begin breeding. Then the females will carry their young through the following rainy season and give birth when the next dry season begins. We have no proven information why this happens, yet, but using some inference, this pattern probably provides females with more consistent access to food while they are pregnant. They carry their young for about 10 months, so it’s important to be healthy and well fed. 
The young are born in the dry season when waters are lower and calmer. This makes it easier for them to get to the surface of the water and that is important because Typhlonectes natans must surface to breath air. The young are in danger of drowning if they can’t breath air from the surface of the water. 
While they are growing inside mom, the young scrap a secretion from the mother’s uterine wall to nourish themselves. They have small fetal teeth that help them collect these nutrients. I can’t believe there is another species of caecilian that eats its mother! 
The developing young also have gills which allows the female to pass oxygen to them in utero. When the young are born, the gills are already gone or disappear within two days. After birth the young will begin to eat small, soft invertebrates within a few days and do not rely on mom for anything. 
Females are not the only one’s involved in the reproductive process. Let’s take a quick moment, because that’s all it’s going to take, to talk about what the male contributes to the next generation of caecilians. Unlike all other amphibians, that we currently know of, caecilian reproduction is internal. Most amphibians lay eggs that are fertilized after they are laid. Caecilian males have a phallodeum which is an organ that they use to pass sperm into the female through her cloaca. No other amphibian does this. With every episode I make, these caecilians become more and more fascinating.
Whether in the water or underground, the males and females twine their bodies together aligning their cloacas up with each other. Then the male inserts his phallodeum into her cloaca and passes her his sperm. A month after mating eggs are either laid or pregnancy indicators, such as weight gain and size growth, are seen.  
All of the behaviors I talked about in this episode are based on observations of just a few species of caecilians and may not apply to other species. There is so much more we have to learn about them and hopefully we’ll be able to do that in the future.
That’s all I wrote about caecilian reproduction and I trust hope you found it as fascinating as I did because it is my seventh favorite thing about the unknown amphibian.
 
If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change. 
 
Join me next week for another thing I like about caecilians!
 
(Piano Music plays) 
This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.

Caecilians: Diet

Wednesday May 03, 2023

Wednesday May 03, 2023

Summary: What do these secretive amphibians eat? Join Kiersten as she takes you on a culinary journey in this episode on caecilian diet.
 
For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean.
 
Show Notes: 
“Caecilian jaw-closing mechanics: integrating two muscle systems” by Thomas Kleinteich, Alexander Haas, and Adam P. Summers. J R Soc Interface, 2008 Dec 6: 5(29): 1491-1504. doi: 10.1098/rsif.2008.0155
 
“Diet of the Banana Caecilian Ichthyophis bannanicus in Mekong Delta, Vietnam” by Binh V. Ngo, Nghiep T. Hoang, and Chung D Ego. Journal of Herpetology, 48(4):506-513 (2014). doi.org/10.1670/13-113.
 
“Rotational feeding in caecilians: putting a spin on the evolution of cranial design” by G. John Easy and Anthony Herrel. Biology Letters (2006) 2, 485-487. doi: 10.1098/rsbl.2006.0516
 
“Dietary Partitioning in Two Co-occurring Caecilian Species (Geotrypetes seraphim and Herepele squalostoma) in Central Africa” by M. T. Kouete and D. C. Blackburn, Integr Org Bill, 2020; 2(1). doi:10.1093/iob/obz035 
 
Music written and performed by Katherine Camp
 
Transcript
(Piano music plays)
Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.
(Piano music stops)
Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right out side our doors and some are continents away but all are fascinating. 
This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.
This episode continues caecilians and the sixth thing I like about these awesome amphibians is their diet.
Our understanding of what and how caecilians eat is still evolving but we know enough to know that it is fascinating!
First, let’s talk about what they eat. Caecilians are carnivores. That means they eat meat. There have been enough studies into various species of caecilians that we have a decent idea of what prey items they tend to eat. In general they focus on invertebrates that are commonly found where they live, underground, in the leaf litter of tropical forests, and underwater. Some examples include ants, termites, earthworms, snails, and some caecilians have been recorded eating crabs, lizards, frogs, and blind snakes. Aquatic caecilians eat fish and aquatic invertebrates. You probably get the drift, if it’s an insect or small animal that lives where caecilians live and it fits in their mouth, they’ll eat it.
Since caecilians have no limbs to help them catch or stabilize prey items their jaw muscles and skulls have evolved to produce a high bite force to help prevent prey items from squiggling away. Caecilians have developed a double jaw muscle mechanism that is special to these amphibians. These muscles are different from other vertebrates because they are actually located above and below the jaw as opposed to the side of the jaw. Take a moment here and place your hands on the side of your jaw. Now open and close your mouth. What you feel moving is your jaw muscles. 
If we were able to place our hands on the sides of a caecilian’s jaw, we would not feel those muscles. Scientists think that the placement of the  muscles on the top and bottom of the skull may be due to the close confines of burrows in which the caecilians live and hunt. Whatever the reason it’s one more cool adaptations these amphibians have developed.
In the last episode we talked about the two different skull formations found in caecilians. At first thought, these differences might be due to the burrowing needs of the caecilian, but upon studying bite force and diet the different skull formations may actually be related to bite force. Caecilians who have the perforated, or zygokrotaphic, skull structure utilize the leverage from the two jaw muscles more efficiently than caecilians with the completely roofed, or stegokrotaphic, skull. What exactly does this information indicate? We’re not quite sure yet. We need more research to determine what these results may mean. For now, we’ll just have to settle for the knowledge itself.
Scientists, being the inquisitive people that they are, asked if caecilians might specialize in specific diet items. Two pieces of evidence leans us towards yes as the answer. One piece of evidence supporting this is tooth shape. Caecilains that eat mostly soft-bodied invertebrates, like earthworms, tend to have sharp curved teeth. This allows the teeth to hook into soft tissue and hold tight. Caecilians that tend to eat prey items that have a harder shell, such as snails, have flatter, pedestal style teeth. This allows them to crush and grind the hard shell. 
While we’re talking about teeth, let me toss this cool fact out there. Caecilians have two rows of teeth in their top jaw and may have one to two rows in the bottom jaw! Forgive my side trip, I just couldn’t resist telling you this fascinating fact.
The second form of evidence supporting diet specialization comes from a study done with two species of caecilians that live in the same area but in different layers of soil. Researchers analyzed the diet of Geotrypetes seraphini and Herpele squalostoma two terrestrial caecilians from Central Africa. G. seraphini lives lower in the soil and eats mostly earthworms, while mole crickets which are found higher in the soil or in leaf litter above ground dominated H. squalostoma’s diet. Now, we don’t know if the diet is dependent on where they live or if they live where their preferred diet can be found. That is a study for the future.
Caecilians just can’t stop surprising us! In another study looking at feeding  behavior of caecilians scientists discovered that these amphibians utilize  rotational feeding. What exactly is rotational feeding? Think about those nature programs you’ve seen about African animals being snatched up by a crocodile. The crocodile often catches something larger than it can swallow in one gulp and spins length wise. This behavior is used to reduce the size of a prey item so it can be easily consumed.
In this study, two species of terrestrial caecilians were observed and recorded eating. They caught both species using rotational feeding to successfully maneuver large prey items into their mouths, just like crocodiles. Unexpectedly, the researchers also observed the caecilians using rotational feeding even when they caught smaller prey items that easily fit into their mouths. So the question is why do they spin when the prey item fits easily into their mouth? We don’t have a solid answer to that question yet, but the researchers postulated that because caecilians are blind maybe they are using the rotational feeding to feel the prey item to help them determine what it is. 
The last behavior we’re going to talk about concerning caecilians’ diet is the most fascinating and slightly disturbing food item I’ve come across in all my years as an animal caretaker. Boulengerula taitanus is an African caecilian that begins life by eating its mother’s skin. You heard me correctly, they eat their mother’s skin! What?! 
So, while mom incubates her eggs that she laid in her subterranean tunnel the outer layer of her skin thickens with nutritious fatty lipids. When the young hatch they have special baby teeth that help them shave off the mother’s outer skin layer. This is the only vertebrate known to use this type of parental feeding strategy! I am thankful everyday I wasn’t born bird so my mother didn’t have to puke into my mouth to feed and now I’m thankful I wasn’t born a caecilian so I didn’t have to eat my mother’s skin.
That’s all for this episode and I know you loved this episode on caecilian diets because it’s the most fascinating episode I’ve researched so far and it’s my sixth favorite thing about this amphibian.
If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change. 
 
Join me next week for another thing I like about caecilians!
 
(Piano Music plays) 
This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.

Caecilians: Locomotion

Wednesday Apr 26, 2023

Wednesday Apr 26, 2023

Summary: Caecilians are legless amphibians, so how do they get around? Join Kiersten as she talks about caecilian locomotion.
 
For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean.
 
Show Notes:
“The kinematics of locomotion in caecilians: effects of substrate and body shape” by Anthony Here et. al, J Exp Cool A Ecol Genet Physiol. 2010. Https//pubmed.ncbi.nlm.nih.gov
 
“A comparative study of locomotion in the caecilian Dermophis mexicanus and Typhlonectes natans (Amphibia: Gymnophiona)” by Adam P. Summers and James C. O’Reilly, Zoological  Journal of the Linnean Society, Vol 121, Issue 1, Sept 1997, pls 65-76. Https://doi.org/10.1111/j.1096-3642.1997.tb000147.x
 
Music written and performed by Katherine Camp
 
Transcript
(Piano music plays)
Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.
(Piano music stops)
Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right outside our doors and some are continents away but all are fascinating. 
This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.
This episode continues caecilians and the fifth thing I like about these supercool amphibians is the way they get around. 
In previous episodes, we have clearly established that caecilians do not have legs, so you may have been asking yourself, how do they get around? Excellent question. Let’s get the answer.
Caecilians are definitely not the only no-legged animal on planet Earth. There are snakes, glass lizards, and fish that do not have legs. Each of these examples have a unique way of locomotion. Caecilian locomotion is something that blows my mind!     
In the last episode we learned that caecilians are divided into ten different families. Most of those families are terrestrial, which means, according to the Oxford Dictionary, of, on, or relating to the earth. Furthermore, many terrestrial caecilians, are fossorial which means they live underground. Nine of our ten families are considered terrestrial caecilians.
So how exactly do caecilians create motion? They use hydrostatic movement. Hydrostatic motion is created when one set of muscles contracts in a circular and longitudinal pattern and another set of muscles stretches in response. Think of how a jellyfish moves. That in and out, almost like breathing, motion is how hydrostatic movement works. Many species of invertebrates use hydrostatic systems to move and several species of vertebrates use hydrostatic systems in specific body parts. 
What makes caecilian hydrostatic locomotion unique is that they are the first known vertebrate to use their entire body as a hydrostatic system for locomotion. How could this get more interesting? I shall tell you! Hydrostatic movement generally depends on utilizing fluid filled portions of the body or vertebrae, but caecilians hydrostatic motion depends on a criss-cross array of tendons that surround their body cavity. Caecilians' skin and skeleton move independently of each other. Muscles do not attach the skin to the skeleton like other vertebrates. This allows them to create twice the maximum forward force of similar sized burrowing snakes that rely on longitudinal movement. 
This is one more example of what makes caecilians so unique in the animal kingdom.
Now that we know exactly how terrestrial caecilians create forward motion let’s look at another characteristic that is influenced by their fossorial lifestyle.
As you know, caecilians don’t have feet, so instead their skull bones have adapted into the perfect shape to move through the soil. They’re skulls are often described as wedge-shaped, compact, and robust. Sounds a lot like a shovel which would be perfect for digging through soil!
Fossorial caecilians’ skull bones have actually fused together in ways that other animals’ skull bones are not fused. There are two types of skull structures in caecilians. The first type is zygokrotaphic in which the skull is perforated between the squamosal, or the side of the skull and the parietal, or the top of the skull. The second type of skull is stegokrotaphic which means the skull in completely roofed. 
These two skull types are incredibly interesting to researchers and have inspired several scientific studies. One study investigated whether the amount of tunneling a species does determines which skull formation is found in their family. The thought was that the completely roofed skull formation would be  better suited to caecilians that burrow in soil more than other species that live mainly in leaf litter. To withstand the force needed to push through the soil a completely fused skull would be better, right? 
What investigators found did not support this hypothesis. There was no evidence showing caecilians with stegokrotaphic skulls had increased burrowing activity. Skull shape may be more influenced by what they eat instead, we’ll talk about this more in next week’s episode.
While investigating this hypothesis the researchers did discover that cranial shape varies greatly throughout caecilians. Even though there is variability in the position of the mouth, the temporal perforation of the skull, and the closure of the eye orbits, caecilian skulls are are generally bullet shaped which helps make burrowing much easier. 
Scientists are always asking questions and a group of researchers studying caecilian movement wanted to know if the length of a caecilian impacted the way they moved. Using x-ray video these scientists recorded the movement of five different species of caecilian that ranged in size. What they discovered was that as the length of the caecilian increased their ability to create the internal concertina motion of hydrostatic movement decreased. As the caecilians increased in length they lost the skin and skeletal independent movement because of the increase in body length. The larger species depended more on lateral movement, even though they are still capable of concertina movement. 
On an interesting note, in all species locomotion choice was dependent on substrate. When they were burrowing through soil they used a whole body or concertina motion to move forward; yet, when they were above the soil they used a lateral movement. This movement is similar to how snakes move in that side to side slithering motion.
Family Typhlonectidae contains our aquatic caecilians. There are 13 species in this family and they all live their entire lives under the water. They also burrow into soil but since the substrate is underwater it’s often more sandy or silty. Many species in this family have lost the concertina movement of terrestrial caecilians. Instead, they rely on a lateral motion to move through the water and soft substrate.
That’s it for caecilian locomotion, I hope you enjoyed this episode because it’s my fifth favorite thing about this awesome animal.
If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change. 
 
Join me next week for another thing I like about caecilians!
 
(Piano Music plays) 
This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.

Image

Ten Things I Like About....

This is Ten Things I Like About.... a 10 minute, 10 episode podcast about unknown or misunderstood wildlife. Each series of ten episodes will focus on different attributes of a specific animal or plant. 

Copyright 2022 All rights reserved.

Podcast Powered By Podbean

Version: 20241125