Thanks to Sy and Finn for their suggestions this week!
Further reading:
Creeping Crinoids! Sea Lilies Crawl to Escape Predators, New Video Shows
New and Unusual Crinoid Discovered
Sea otters maintain remnants of healthy kelp forest amid sea urchin barrens
Sea urchins see with their feet
A sea lily [photo from this page]:
A feather star [still from a video posted on this page]:
Purple urchins [photo by James Maughn]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This week as we bring invertebrate August to a close, we’re going to cover some animals suggested by Finn and Sy.
We’ll start with Sy’s suggestion, crinoids, also called feather stars or sea lilies depending on what body plan a particular species has. We talked about them in episode 79 but it’s definitely time to revisit them.
Crinoids are echinoderms, a really old phylum of animals. Fossils of ancient echinoderms date back to the Cambrian half a billion years ago and they’re still incredibly common throughout the world’s oceans.
Ancient crinoids had five arms the way many starfish do, which makes sense because crinoids are related to starfish. At some point each arm developed into two, so many crinoids have ten arms or even more, and many have arms that branch. The arms are used for feeding and have feathery appendages lined with sticky mucus that traps tiny bits of food floating in the water.
There are two big divisions of crinoids today, the feather stars and the sea lilies. Feather stars are more common and can swim around as adults if they want to, although most stick to crawling along the sea floor. They swim by waving their feathery arms. Sea lilies look like flowers as adults, with a slender stem-like structure with the small body and long feathery arms at the top. I specify that sea lilies have stems as adults because a lot of feather stars also have stems as juveniles, but when they reach maturity they become free-swimming.
Even though the sea lily looks like a plant, and some species even have root-like filaments that help it anchor itself to the sea floor or to rocks, it’s still an animal. For one thing, it can uproot itself and move to a better location if it wants to, crawling with its arms and pulling its stem behind it, which is not something a plant can do except in cartoons. If a predator attacks it, the sea lily will even shed its stem completely so it can crawl away much faster. Since echinoderms in general are really good at regenerating parts of the body, losing its stem isn’t a big deal.
The biggest sea lilies today are deep-sea species, but even they only grow a stem up to about three feet long at most, or about a meter. This wasn’t the case in the ancient past, though. The longest crinoid stem fossil ever discovered was 130 feet long, or 40 meters.
Crinoids filter food particles from the water that flows through the feathery arms. Even though they look like feathers or petals, a crinoid’s arms are actually arms. They have tiny tube feet on them that act sort of like fingers to help the crinoid hold onto pieces of food, and to do a better job of holding the food, the tube feet are covered with a sticky mucus. The mouth is in the middle of the arms on the top of the body.
Crinoids absorb oxygen directly from the water. Its body contains a system of chambers and pores that are full of water, and by contracting special muscles, the crinoid moves water around in its body to transport nutrients and oxygen and to collect waste material.
Crinoids are closely related to starfish, sea cucumbers, sand dollars, and sea urchins, which brings us to Finn’s suggestion. Finn suggested urchins, which are also echinoderms. In fact, at the end of episode 79 I mentioned that one day I’d do an episode about urchins, and it only took me six years to get here!
Many urchins look like living pincushions because they’re covered in spines. That’s where the name urchin comes from,
Episode 394: Mantis Shrimp!
lundi 19 août 2024 • Durée 11:44
Thanks to Anbo and Siya for suggesting the mantis shrimp this week!
The Kickstarter for some animal-themed enamel pins is still going on!
Further reading:
Rolling with the punches: How mantis shrimp defend against high-speed strikes
The magnificent peacock mantis shrimp [picture by Cédric Péneau, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=117431670]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
As invertebrate August continues, this week we have a topic suggested by Anbo and Siya. They both wanted to learn about the mantis shrimp!
The mantis shrimp, which is properly called a stomatopod, is a crustacean that looks sort of like a lobster without the bulky front end, or a really big crayfish. Despite its name, it’s not a shrimp although it is related to shrimps, but it’s more closely related to lobsters and crabs. It can grow as much as 18 inches long, or 46 cm, but most are about half that size. Most are brown but there are hundreds of different species and some are various brighter colors like pink, blue, orange, red, or bright green, or a rainbow of colors and patterns.
There are two things almost everyone knows about the mantis shrimp. One, it can punch so hard with its claws that it breaks aquarium glass, and two, it has 12 to 16 types of photoreceptor cells compared to 3 that humans have, and therefore it must be able to see colors humans can’t possibly imagine.
One of those things is right, but one is wrong, or at least partially wrong. We’ll discuss both in a minute, but first let’s learn the basics about these fascinating animals.
The mantis shrimp lives in shallow water and spends most of its time in a burrow that it digs either in the sea floor or in crevices in rocks or coral, which it enlarges if necessary. Some species will dig elaborate tunnel systems while others just wedge themselves into any old crack that will hide them. It molts its exoskeleton periodically as it grows, like other crustaceans, and after that it either has to expand its burrow or move to a larger one. Most species live in tropical or subtropical areas, but some prefer more temperate waters.
It has eight pairs of legs, which includes three pairs of walking legs, four pairs with claws that help it grasp items, and its front pair, which are hinged and look a little like the front legs of a praying mantis. That’s where the “mantis” in mantis shrimp comes from, although of course it has lots of other names worldwide. In some places it’s called the thumb splitter.
The mantis shrimp has two eyes on stalks that move independently. Its brain extends into the eye stalks, and the section of the brain in the eye stalks, called the reniform body, is what processes vision. This allows it to process a lot of visual information very quickly. Reniform bodies have also been identified in the brains of some other crustaceans, including shrimp, crayfish, and some crabs. Scientists also think that the eyes themselves do a lot of visual processing before that information gets to the reniform body or the brain at all. In other words, part of the reason the mantis shrimp’s eyes are so complicated and so unusual compared to other animals’ eyes is because each eye is sort of a tiny additional brain that mainly processes color.
The typical human eye can only sense three wavelengths of light, which correspond to red, green, and blue. The mantis shrimp has twelve different photoreceptors instead of three, meaning it can sense twelve wavelengths of light, and some species have even more photoreceptors. But while our brains are really good at synthesizing the three wavelengths of light we can see, combining them so that we see incredibly fine gradations of color in between red, green, and blue, the mantis shrimp doesn’t process color the same way we do. So while its eyes can sense colors we can’t, its brain doesn’t seem to do anything with the color information.
Episode 385: More Monitors
lundi 17 juin 2024 • Durée 09:18
Thanks to Cosmo and Zachary for suggesting this week's monitor lizards!
Further reading:
No One Imagined Giant Lizard Nests Would Be This Weird
The Mighty Modifications of the Yellow-Spotted Goanna
The Asian water monitor:
A yellow-spotted goanna standing up [picture by Geowombats - https://www.flickr.com/photos/geowombats/136601260/, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=2595566]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
Last week we had our big dragons episode where we learned about the Komodo dragon and some of its relations, including goannas. I forgot to thank Cosmo for suggesting the lace monitor, also called the tree goanna, in that episode, and I also forgot that Zachary had also suggested monitor lizards as a topic, so let’s learn about two more monitor lizards this week.
Cosmo is particularly interested in aquatic and semi-aquatic animals, and a lot of monitor lizards are semi-aquatic. Let’s learn about the Asian water monitor first, since it’s the second-largest lizard alive today, only smaller than the Komodo dragon.
The Asian water monitor is common in many parts of South and Southeast Asia, including India, Vietnam, Cambodia, Laos, southern China, and many islands. A half dozen subspecies are currently recognized, although there may be more.
The largest water monitor ever reliably measured was 10 1/2 feet long, or 3.2 meters. It’s dark brown or black with yellow speckles and streaks, and young lizards have larger yellow spots and stripes. It lives wherever it can find fresh or brackish water, from lakes and rivers to swamps, ponds, and even sewers.
Like the crocodile, the Asian water monitor’s tail is flattened from side to side, called lateral compression, and it’s also very strong. It swims by tucking its legs against its sides and propelling itself through the water with its tail. It can dive deeply to find food, and while it prefers fresh water, it will swim in the ocean too. That’s why it’s found on so many islands.
Juvenile Asian water monitors spend most of the time in trees, but even a fully grown lizard will sometimes climb a tree to escape danger. Only saltwater crocodiles and humans kill the adults.
In some parts of its range, the water monitor is killed by humans for its meat and its skin, which is used as leather. In other parts of its range, it’s never bothered since it eats venomous snakes and animals that damage crops. It’s sometimes kept as a pet, although it can grow so big that many people who buy a baby water monitor eventually run out of room to keep it. That’s how so many have ended up in the waterways of Florida and other areas far outside of its natural range, from people letting pets go in the wild even though doing so is illegal and immoral.
While most of the time the water monitor isn’t dangerous to humans, if it feels threatened, it can be quite dangerous. Like the Komodo dragon and other monitor lizards, it’s venomous, plus its teeth are serrated, its jaws are strong, and it has sharp claws. It eats a lot of carrion, along with anything it can catch. A population in Java even enters caves to hunt bats that fall from the ceiling.
Zachary didn’t suggest a particular type of monitor lizard, so let’s learn about the yellow-spotted goanna. Goannas are a type of monitor lizard found in Australia, New Guinea, and some nearby areas. We talked about some of them last week, including Cosmos’s suggestion of the lace monitor, but after the episode was released I found an article I had saved over a year ago. It’s about the yellow-spotted goanna, and a remarkable discovery about how it takes care of its eggs.
The yellow-spotted goanna lives in parts of Australia and southern New Guinea, and a big male can grow up to five feet long, or 1.5 meters. It can swim and climb trees when it wants to, but mainly it stays on the ground, although it prefers to live near water if possible.
Episode 295: The Peregrine Falcon
lundi 26 septembre 2022 • Durée 10:29
Thanks to Nikita for this week's suggestion that we learn all about the peregrine falcon!
I'll be at the Next Chapter Book Fair in Dalton, Georgia on October 1, 2022! Come say hi!
Further listening:
Crossover episode with Arcane Carolinas from ConCarolinas 2022!
Further reading:
Falcons see prey at speed of Formula 1 car
A peregrine falcon in flight:
Baby peregrine falcons. Look at those giant peets! [photos by Robin Duska, taken from this site]
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This week we have a suggestion from Nikita, who wants to learn about the peregrine falcon! The peregrine falcon is the fastest animal known, and I thought about trying to talk very fast for this episode, but I decided I make enough mistakes just talking normally.
A quick note before we start. On Saturday, October 1, 2022, I’ll be at the Next Chapter Book Fair and Convention in Dalton, Georgia. If you happen to be in the area, stop by and say hi! I’ll be selling books and I think I’m on a panel too. That’s the last event I have planned for the year and I’m not sure if I’ll be selling books at conventions next year. It’s fun, but it’s also a lot of work. Whatever copies of the Beyond Bigfoot & Nessie book that don’t sell next week, I can offer for sale directly from me. If you want a signed copy of a slightly banged-up paperback that’s been to a lot of conventions, email me and we can work out a price with shipping.
Speaking of conventions, back in June I had a fantastic time at ConCarolinas, and one of the things I did was join the guys from Arcane Carolinas to record an episode of their excellent podcast. Well, they’ve just released that episode and it’s fantastic! I’ll put a link in the show notes in case you don’t already listen to their podcast.
Now, let’s learn about the peregrine falcon!
The peregrine falcon lives throughout the world, with as many as 19 subspecies, although experts disagree about a few of those. It’s about the size of a crow, with females being much bigger than males. Different subspecies have different patterns, but in general the peregrine falcon is dark above and pale below with a darker barred pattern. It has bright yellow around its eyes, and the base of its hooked bill and its feet are yellow.
The peregrine mates for life, and reuses the same nesting site every year. Some populations of peregrine migrate long distances, and sometimes the male will stay year-round near the nesting site while the female migrates. Either way, at the beginning of the breeding season, which is usually around the end of winter, the pair performs courtship flights where the male will pass food to the female while they’re both flying. Sometimes the female turns over to fly upside-down to take food from her mate.
The male typically prepares several potential nesting sites, and the female chooses which one she likes best to lay her eggs. The peregrine doesn’t build a nest, though, just kicks at the dirt to make what’s called a scrape. It’s just a shallow depression in the dirt. The female lays 2 to 5 eggs that hatch in about a month into fuzzy white babies with gigantic talons. Both parents help incubate the eggs and both feed the babies after they hatch.
The peregrine especially likes open areas with cliffs for its nest, and as far as it’s concerned, skyscrapers are just a type of cliff. It’s surprisingly common in cities as a result, not to mention that cities are home to another bird, the pigeon, that the peregrine loves to eat. The peregrine mostly eats birds, especially pigeons, gulls, ducks, and various songbirds, but it will also eat bats and sometimes small animals like squirrels and rats. It mostly hunts at dawn and dusk, but it will hunt at night too and sometimes during the day.
Even though the peregrine isn’t very big compared to many birds of prey like eagles, owls, and hawks, it is an astounding hunter.
Episode 294: Updates 5 and a New Zealand Parrot!
lundi 19 septembre 2022 • Durée 17:34
It's our fifth updates and corrections episode, with some fun information about a New Zealand parrot, suggested by Pranav! Thanks also to Llewelly, Zachary, Nicholas, and Simon who sent in corrections.
Further reading:
Vitiligo
Tyrannosaurus remains hint at three possible distinct species
Study refutes claim that T. rex was three separate species
The reign of the dinosaurs ended in spring
Impact crater may be dinosaur killer’s baby cousin
California mice eat monarch butterflies
'Hobbit' human story gets a twist, thanks to thousands of rat bones
Playground aims to distract mischievous kea
The kea showing off the bright colors under its wings:
A kea jungle gym set up to stop the birds from moving traffic cones around for fun:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This is our fifth annual updates episode, where I catch us up on new studies published about various animals we’ve talked about before. This is mostly just whatever happens to catch my eye and isn’t comprehensive by any means. Also, because things have been so busy for me the last few weeks, I decided to just go with what I’d already finished and not try to add more.
We’ll start as usual with corrections, then do some updates, then learn about a parrot from New Zealand, which was a suggestion from Pranav. This part of the episode started as a Patreon episode from 2019, so patrons, I promise your October bonus episode will be brand new and interesting and in-depth!
First, both Llewelly and Zachary pointed out that there are lions living in Asia, not just Africa. It’s called the Asiatic lion and these days, it only lives in a few small areas in India. It’s a protected animal but even though their numbers are increasing, there are probably still no more than 700 Asiatic lions living in the wild.
Next, Nicholas points out that vitiligo isn’t a genetic condition, it’s an autoimmune disorder that can be caused by a number of different diseases and conditions. You still can’t catch it from other people, though. We talked about vitiligo briefly in episode 241, about squirrels. Nicholas included a link, which I’ll put in the show notes for anyone who’s interested in learning more.
For our final correction, Simon questioned whether there really are only six living species of macaw known. This was polite of him, since I was completely wrong about this. In fact, there are six genera of macaws and lots of species, although how many species there are exactly depends on who you ask. Since this mistake made it into the Beyond Bigfoot & Nessie book, I am very irritated at myself, but thank you to Simon for helping me clear this up.
Let’s start our updates with the animal who gets an update every single time, Tyrannosaurus rex. A study published in February 2022 examined the fossilized remains of 37 T. rexes and suggested that there may actually be three distinct species of T. rex instead of just one. The study focused specifically on differences in teeth and leg bones that don’t seem to have anything to do with the individual’s age when it died or whether it was male or female.
However, in July 2022, another study found that all the T. rexes found so far do indeed belong to the same species. This is how science works, because new information is always being discovered and that means we have to reassess the things we thought we knew.
In other dinosaur news, in episode 240 we talked about the last day of the dinosaurs. Results of a study released in February 2022 suggest that the asteroid struck in early spring in the northern hemisphere. The asteroid hit the earth so hard that it rocked the entire continental plate that it struck, which caused massive waves unlike any other waves, since all the water above the continental plate was pushed upwards at once. This pushed all the sediment lying quietly on the bottom of the ocean up into the water,
Episode 293: Bat-Winged Dinosaurs and an Actual Bat
lundi 12 septembre 2022 • Durée 16:20
We'll have a real episode next week but for now, here are two Patreon episodes smashed together into one!
Happy birthday to Speed!
Further reading:
Yi qi Is Neat But Might Not Have Been the Black Screaming Dino-Dragon of Death
Yi qi could probably glide instead of actually flying:
The Dayak fruit bat [photo by Chien C. Lee]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
I’ve finally finished moving, although I’m still in the process of unpacking and finding places for all my stuff. I haven’t had the chance to do any research this week, so this episode is actually two repurposed Patreon episodes, one from June of 2019 and one from May of 2021. They’re both short episodes so I put them together. I apologize to patrons for not getting something new this week, but I think everyone else will find these animals interesting.
But first, we have a birthday shout-out! A great big happy birthday to Speed! I hope this next year is the very best one yet for you!
Please excuse the varying quality of audio.
Listener Simon sent me an article about a recently discovered dinosaur with batlike wings, only the second batwinged dinosaur ever discovered. I thought that would make a really neat episode, so thank you, Simon!
These are really recent discoveries, both from the same area of northeastern China. In 2007 a small fossil found by a farmer was bought by a museum. A paleontologist named Xing Xu thought it looked interesting. Once the fossil had been cleaned and prepared for study, Xing saw just how interesting it was.
The dinosaur was eventually named Yi qi, which means strange wing. It was found in rocks dated to about 163 million years ago. Yi qi was about the size of a pigeon and was covered with feathers. The feathers were probably fluffy rather than the sleek feathers of modern birds. But most unusual was a long bony rod that grew from each wrist, called a styliform element. Yi qi also had very long third fingers on each hand. The long finger was connected to the wrist rod by a patagium, or skin membrane, and another patagium connected the wrist rod to the body. So even though it had feathers on its body, it probably didn’t have feathered wings. Instead, its forelimbs would have somewhat resembled a bat’s wings.
Paleontologists have studied the fossilized feathers with an electron microscope and discovered the structures of pigments that would have given the feathers color. Yi qi was probably mostly black with yellow or brown feathers on the head and arms. It probably also had long tail feathers to help stabilize it in the air.
Ambopteryx longibrachium was only discovered in 2017, also in northeastern China. It also lived around 163 million years ago and looked a lot like Yi qi. The fossil is so detailed it shows an impression of fuzzy feathers and even the contents of the animal’s digestive tract. Its body contained tiny gizzard stones to help it digest plants but also some bone fragments from its last meal, so paleontologists think it was an omnivore. Its hands have styliform elements, although not a wrist rod like Yi qi, and there’s a brownish film preserved across one of its arms that researchers think are remains of a wing membrane.
Paleontologists think the bat-winged dinosaurs were technically gliders. Careful examination of the wrist rods show no evidence that muscles were attached, so the dinosaurs wouldn’t have been able to adjust the wings well enough to actually fly. Modern bats have lots of tiny muscles in their wing membranes to help them fly.
Yi qi’s wrist rod isn’t unique in the animal world. The flying squirrel has styliform rods made of cartilage that project from the wrists, with the patagia attached to them. When a squirrel wants to glide, it extends its arms and legs and also extends the wrist rods, stretching the patagia taut. It can even control its glide to some extent by adjusting the wrist rods.
These two bat-winged dinosaurs were related,
Episode 292: The Kunga
lundi 5 septembre 2022 • Durée 07:52
This week let's learn about a mystery that was solved by science!
Happy birthday to Zoe!
Further reading:
Let's all do the kunga!
The kunga, as depicted in a 4500-year-old mosaic:
The Syrian wild ass as depicted in a 1915 photograph (note the size of the animal compared to the man standing behind it):
Domestic donkeys:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
As this episode goes live, I should be on my way home from Dragon Con, ready to finish moving into my new apartment! It’s been an extremely busy week, so we’re just going to have a short episode about a historical mystery that was recently solved by science.
But first, we have another birthday shout-out! Happy birthday to Zoe, and I hope you have the most sparkly and exciting birthday ever, unless you’d rather have a chill and low-key birthday, which is just as good depending on your mood.
This week we’re going to learn about an animal called the kunga, which I learned about on Dr. Karl Shuker’s blog. There’s a link in the show notes if you’d like to read his original post.
The mystery of the kunga goes back thousands of years, to the fertile crescent in the Middle East. We’ve talked about this area before in episode 177, about the sirrush, specifically Mesopotamia. I’ll quote from that episode to give you some background:
"These days the countries of Iraq and Kuwait, parts of Turkey and Syria, and a little sliver of Iran are all within what was once called Mesopotamia. It’s part of what’s sometimes referred to as the Fertile Crescent in the Middle East. The known history of this region goes back five thousand years in written history, but people have lived there much, much longer. Some 50,000 years ago humans migrated from Africa into the area, found it a really nice place to live, and settled there.
"Parts of it are marshy but it’s overall a semi-arid climate, with desert to the north. People developed agriculture in the Fertile Crescent, including irrigation, but many cultures specialized in fishing or nomadic grazing of animals they domesticated, including sheep, goats, and camels. As the centuries passed, the cultures of the area became more and more sophisticated, with big cities, elaborate trade routes, and stupendous artwork."
The domestic horse wasn’t introduced to this area until about 4,000 years ago, although donkeys were common. The domestic donkey is still around today, of course, and is descended from the African wild ass. Researchers estimate it was domesticated 5- or 6,000 years ago by the ancient nomadic peoples of Nubia, and quickly spread throughout the Middle East and into southern Asia and Europe.
But although horses weren’t known in the Middle East 4,500 years ago, we have artwork that shows an animal that looks like a really big donkey, much larger than the donkeys known at the time. It was called the kunga and was highly prized as a beast of burden since it was larger and stronger than an ordinary donkey. It was also rare, bred only in Syria and exported at high prices. No one outside of Syria knew what kind of animal the kunga really was, but we have writings that suggest it was a hybrid animal of some kind. This explains why its breeding was such a secret and why it couldn’t be bred elsewhere. Many hybrid animals are infertile and can’t have babies.
If the artwork was from later times, we could assume it showed mules, the offspring of a horse and a donkey. But horses definitely weren’t known in the Middle East or nearby areas at this time, so it can’t have been a mule.
The kunga was used as a beast of burden to pull plows and wagons, but the largest individuals were used to pull the chariots of kings. Fortunately, the kunga was so highly prized that it was sometimes sacrificed and buried with important people as part of their grave goods. Archaeologists have found a number of kunga skeletons, together with ceremonial harnesses.
Episode 291: The Ediacaran Biota
lundi 29 août 2022 • Durée 16:04
This week let's find out what lived before the Cambrian explosion!
A very happy birthday to Isaac!
Further reading:
Some of Earth's first animals--including a mysterious, alien-looking creature--are spilling out of Canadian rocks
Say Hello to Dickinsonia, the Animal Kingdom's Newest (and Oldest) Member
Charnia looks like a leaf or feather:
Kimberella looks like a lost earring:
Dickinsonia looks like one of those astronaut footprints on the moon:
Spriggina looks like a centipede no a trilobite no a polychaete worm no a
Glide reflection is hard to describe unless you look at pictures:
Trilobozoans look like the Manx flag or a cloverleaf roll:
Cochleatina looked like a snail:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
It’s the last week of August 2022, so let’s close out invertebrate August with a whole slew of mystery fossils, all invertebrates.
But first, we have a birthday shoutout! A humongous happy birthday to Isaac! Whatever your favorite thing is, I hope it happens on your birthday, unless your favorite thing is a kaiju attack.
We’ve talked about the Cambrian explosion before, especially in episode 69 about some of the Burgess shale animals. “Cambrian explosion” is the term for a time starting around 540 million years ago, when diverse and often bizarre-looking animals suddenly appear in the fossil record. But we haven’t talked much about what lived before the Cambrian explosion, so let’s talk specifically about the Ediacaran (eedee-ACK-eron) biota!
I was halfway through researching this episode when I remembered I’d done a Patreon episode about it in 2021. Patrons may recognize that I used part of the Patreon episode in this one. You’d think that would save me time but surprise, it did not.
The word Ediacara comes from a range of hills in South Australia, where in 1946 a geologist noticed what he thought were fossilized impressions of jellyfish in the rocks. At the time the rocks were dated to the early Cambrian period, and this was long before the Cambrian explosion was recognized as a thing at all, much less such an important thing. But since then, geologists and paleontologists have reevaluated the hills and determined that they’re much older than the Cambrian, dating to between 635 to 539 million years ago. That’s as much as 100 million years before the Cambrian. The Ediacaran period was formally designated in 2004 to mark this entire period of time, although fossils of Ediacaran animals generally start appearing about 580 million years ago.
Here’s something interesting, by the way. During the Ediacaran period, every day was only 22 hours long instead of 24, and there were about 400 days in a year instead of 365. The moon was closer to the earth too. And life on earth was still sorting out the details.
Fossils from the Ediacaran period have been discovered in other places besides Australia, including Namibia in southern Africa, Newfoundland in eastern Canada, England, northwestern Russia, and southern China. Once the first well-preserved fossils started being found, in Newfoundland in 1967, paleontologists started to really take notice, because they turned out to be extremely weird. The fossils, not the paleontologists.
Many organisms that lived during this time lived on, in, or under microbial mats on the sea floor or at the bottoms of rivers. Microbial mats are colonies of microorganisms like bacteria that grow on surfaces that are either submerged or just tend to stay damp. Microbial mats are still around today, usually growing in extreme environments like hot springs and hypersaline lakes. But 580 million years ago, they were everywhere.
One problem with the Ediacaran biota, and I should explain that biota just means all the animals and plants that live in a particular place, is that it’s not always clear if a fossil is actually an animal.
Episode 290: Lobsters!
lundi 22 août 2022 • Durée 13:35
Thanks to Pranav for this week's suggestion, lobsters!
Happy birthday to Jake!!
Visit Dr. Oné R. Pagán's site for links to his podcast and his free book Arrow: The Lucky Planarian! You can also order his other books from your favorite book store. Here's the direct link to his interview with me!
Further reading:
Don't Listen to the Buzz: Lobsters Aren't Actually Immortal
An ordinary lobster:
A blue lobster!
The scampi looks more like a prawn/shrimp than a lobster, but it's a lobster:
The rosy lobsterette is naturally red because it lives in the deep sea:
The deep-sea lobster Dinochelus ausubeli was only discovered in 2007 and described in 2010:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
As invertebrate August continues, this week we’re going to talk about lobsters. Thanks to Pranav for the suggestion!
But first, we have a birthday shout-out! A great big happy birthday this week to Jake! I hope your birthday is epic fun!
I’d also like to let you know that Dr. Oné R Pagán interviewed me recently about my book, Beyond Bigfoot & Nessie: Lesser-Known Mystery Animals from Around the World, and you can hear that interview on his podcast, the Baldscientist Podcast. Baldscientist is all one word. I’ll put a link in the show notes. While you’re at it, you should definitely buy his books, including his latest one, Drunk Flies and Stoned Dolphins: A Trip Through the World of Animal Intoxication, which just came out this year and is a lot of fun, as well as being full of interesting science! He also has a free children’s story called Arrow, the Lucky Planarian that you can download and read. It’s completely charming and you’ll learn a lot about planarians, which are also called flatworms, which are invertebrates, so this is all coming together!
This week’s episode isn’t about planarians, though, but about lobsters. I don’t think we’ve ever discussed lobsters on the podcast before, oddly enough, but it’s been on my ideas list for a long time. When Pranav emailed me recently to suggest we do a lobster episode, I realized it was time! Time for lobsters!
The lobster is a crustacean, and while there are plenty of different lobsters in the world, we’re going to focus on the clawed lobsters this time. There are lots of them, all grouped in the family Nephropidae.
The lobster has eight legs that it walks on, and two more legs with pincers. That’s why it’s in the order Decapoda. Deca means ten and poda means feet. Ten feet. Some of which can pinch you if you’re not careful.
The lobster uses its claws to defend itself from potential predators, and uses them to grab and kill small animals. It eats pretty much anything it can find, from fish and squid to sea stars and mollusks, to dead animals and some plant material. But its claws are too big and clumsy to use to eat with, which is why it has much smaller pincers on its next pairs of legs. These pincers are equipped with chemoreceptors that allow the lobster to taste its food before it actually eats it, which is a neat trick.
The lobster uses these small claws to pull its food into smaller pieces and convey it to the mouthparts, which are under its head. Some mouthparts have sensory hairs that can taste food, some have sharp spines that act as teeth to tear food into smaller pieces, and others are small and just flutter to help keep pieces of food from floating away. The stomach is only about an inch away from the mouth, or about 2.5 cm, no matter the size of the lobster. The stomach itself, and the short esophagus leading to the stomach, are lined with chitin spines that act like teeth to grind food up while enzymes break it down to fully digest it. This seems like a really complicated way to eat, but it’s actually not all that different from the way we eat, it’s just that instead of mouthparts and stomach teeth, we do all our grinding up of food in the mouth with just one set of teeth.
Episode 289: Weird Worms
lundi 15 août 2022 • Durée 14:20
This week we learn about some weird worms!
Further reading:
Otherworldly Worms with Three Sexes Discovered in Mono Lake
Bizarre sea worm with regenerative butts named after Godzilla's monstrous nemesis
Underground giant glows in the dark but is rarely seen
Giant Gippsland earthworm (you can listen to one gurgling through its burrow here too)
Further watching:
A giant Gippsland earthworm
Glowing earthworms (photo by Milton Cormier):
This sea worm's head is on the left, its many "butts" on the right [photo from article linked to above]:
A North Auckland worm [photo from article linked to above]:
A giant beach worm:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This week we continue Invertebrate August with a topic I almost saved for monster month in October. Let’s learn about some weird worms!
We’ll start with a newly discovered worm that’s very tiny, and we’ll work our way up to larger worms.
Mono Lake in California is a salty inland lake that probably started forming after a massive volcanic eruption about 760,000 years ago. The eruption left behind a crater called a caldera that slowly filled with water from rain and several creeks. But there’s no outlet from the lake—no river or even stream that carries water from the lake down to the ocean. As a result, the water stays where it is and over the centuries a lot of salts and other minerals have dissolved into the lake from the surrounding rocks. The water is three times as salty as the ocean and very alkaline.
No fish live in the lake, but some extremophiles do. There’s a type of algae that often turns the water bright green, brine shrimp that eat the algae, some unusual flies that dive into the water encased in bubbles, birds that visit the lake and eat the brine shrimp and flies, and eight species of worms that have only been discovered recently. All the worms are weird, but one of them is really weird. It hasn’t been described yet so at the moment is just going by the name Auanema, since the research team thinks it probably belongs in that genus.
Auanema is microscopic and lives throughout the lake, which is unusual because the lake contains high levels of arsenic. You know, a DEADLY POISON. But the arsenic and the salt and the other factors that make the lake inhospitable to most life don’t bother the worms.
Auanema produces offspring that can have one of three sexes: hermaphrodites that can self-fertilize, and males and females that need each other to fertilize eggs. Researchers think that the males and females of the species help maintain genetic diversity while the hermaphrodites are able to colonize new environments, since they don’t need a mate to reproduce.
When some of the worms were brought to the laboratory for further study, they did just fine in normal lab conditions, without extreme levels of arsenic and so forth. That’s unusual, because generally extremophiles are so well adapted for their extreme environments that they can’t live anywhere else. But Auanema is just fine in a non-harsh environment. Not only that, but the team tested other species in the Auanema genus that aren’t extremophiles and discovered that even though they don’t live in water high in arsenic, they tolerate arsenic just as well as the newly discovered species.
The team’s plan is to sequence Auanema’s genome to see if they can determine the genetic factors that confer such high resistance to arsenic.
Next, we go up in size from a teensy worm to another newly discovered worm, this one only about 4 inches long at most, or 10 cm. It’s a marine polychaete worm that lives inside sea sponges, although we don’t know yet if it’s parasitizing the sponge or if it confers some benefit to the sponge that makes this a symbiotic relationship. The worm was only discovered in 2019 near Japan and described in early 2022 as Ramisyllis kingghidorahi.
Almost all worms known are shaped, well, like worms.
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