Monthly Archives: December 2020

Episode 204: Frogs of Many Cheery Colors

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Let’s finish off a very weird year and welcome in the new year with a basket of colorful frogs!

The northern leopard frog comes in many color morphs, all of them pretty:

The starry dwarf frog is also pretty and has an orange tummy:

The astonishing turtle frog:

 

Poison dart frogs are colorful and deadly (blue poison dart frog, golden poison dart frog):

The tomato frog looks like a tomato that is also a frog:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

It’s the very last week of 2020, and good riddance. Let’s kick the old year out the back door and welcome in the new year with a basket of pretty frogs. That’s right, we’ve got a frog episode this week!

Let’s start with the northern leopard frog, with thanks to an anonymous reviewer who gave the podcast a really nice five-star review and only signed the review “norhern lepord frong.” I looked that frog up online to see what it looked like, and it’s so pretty, honestly, it’s just the prettiest frog! If you had a basket of northern leopard frogs, they might just look like friendly flowers, because while most are green or brown with darker spots, some are much brighter green with yellow markings, some are dark brown, and some are even pinkish white because of a rare albino trait. Its spots are outlined with yellow or light green and it has two folds of skin that run the length of the body and are sometimes yellow. These folds of skin are called dorsolateral folds and many frogs have them, although they’re not always as easy to spot as in the northern leopard frog.

The northern leopard frog is native to the northern part of North America, especially southern Canada and the northern and western United States. It grows up to 4.5 inches long, or 11.5 cm, measured from snout to vent. As you may recall from previous frog episodes, that’s how frogs are always measured. It basically just means nose to butt. Females are larger than males, which is also the case for most frogs.

It lives anywhere that it can find fresh water, including rivers, streams, creeks, ponds, marshes, even drainage ditches, but it prefers slow-moving or quiet water. As a result, it’s threatened by loss of habitat, pollution, and climate change, all of which affect the water it needs to live, and it’s also threatened by non-native animals and diseases. But while it doesn’t live in as many places as it used to, right now it’s doing fine overall and isn’t considered endangered.

Like most frogs, the northern leopard frog eats insects and any other small animal it can swallow. It has a long sticky tongue that it can shoot out so quickly that even an insect can’t outfly it, but it doesn’t just eat insects. It’s a big frog with a big mouth, and it’s been recorded eating other species of frog, small snakes, small birds, and even a bat. But mostly it eats insects, slugs, snails, and worms. Probably the frog that was documented as catching and eating a bat is famous in the northern leopard frog world, or at least it would be if real life was like the inside of my head and frogs had their own tiny newspapers.

The northern leopard frog was once considered a delicacy, with most frogs’ legs coming from this particular species. It’s also sometimes kept as a pet. It’s mostly nocturnal and semi-aquatic, sometimes called the meadow frog because it will leave the water to hunt for food in grassy areas. It hibernates in winter but is better adapted to cold weather than a lot of frogs are.

There’s also a southern leopard frog that looks very similar to the northern leopard frog but lives farther south, which you probably guessed from the name. It’s also slightly larger than the northern leopard frog, up to five inches long, or 13 cm.

Male leopard frogs, like many other frogs, have special vocal sacs in the throat that allow a male to make a loud call in spring to attract females. Different species of frog have different calls, naturally, and the vocal sacs are shaped differently in every species. The male leopard frog, northern and southern, has two vocal sacs that he fills with air like balloons, which amplifies the sound of his voice and makes it much louder.

This is what a northern leopard frog sounds like:

[frog sound]

Another colorful frog is from India and was only discovered in 2010. A team of scientists surveying the mountains for reptiles and amphibians noticed a teensy frog in the leaf litter one night. Its back was brown with light blue dots that looked like stars in a night sky, but its belly was orange like a sunset. It’s a very pretty frog.

The researchers caught several of the frogs and thought they were pretty but not especially unusual. There are at least 400 known frogs in India and new species are found pretty frequently. The team named it the starry dwarf frog because of the blue dots and its size, less than 20 mm long, or around half an inch. That’s about the size of an adult’s thumbnail.

After the expedition, though, when the team examined the frogs more closely, they realized they had something different from other frogs. It didn’t seem to be related to any other frog species in India or anywhere else. A genetic analysis indicated that the starry dwarf frog is literally not closely related to any frog alive today. For millions of years India was a big island after it separated from Madagascar and Africa but before it collided with mainland Asia, so many species evolved independently from species in other parts of the world. Scientists hope to learn more about the starry dwarf frog to learn more about how other frogs evolved.

Let’s move on to another colorful frog, and a very weird one, the turtle frog. Simon brought this one to my attention, so thank you, Simon! This frog gets its name because it sort of looks like a tiny turtle without a shell.

The turtle frog lives in western Australia in areas that are much dryer than most frog habitats. Its body is bulbous with strong, stubby legs that allow it to burrow into the sand. Generally, when a frog burrows into sand or mud it does so by moving backwards, digging itself deeper with its strong hind legs. But the turtle frog digs forward, using its front legs to dig. Turtles are also forward diggers. Unlike most other frogs, the turtle frog doesn’t have long hind legs that it uses for jumping. It just has short legs in front and back.

It ranges in color from brown to reddish-brown to pink and it grows up to 2 inches long, or 5 cm. Its head is small, rounded, and distinct from the body, like a baby turtle’s head sticking out from its shell–but without a shell, without a beak, and with small black-dot eyes.

Obviously the turtle frog isn’t related to the turtle at all. Turtles are reptiles while frogs are amphibians. The turtle frog has adapted to a semi-arid climate and a diet of termites by evolving the ability to dig deep burrows, some of them almost four feet deep, or 1.2 meters, and the ability to break into termite nests. As a result, its body plan is different from most other frogs.

That’s not all that’s different, though. Most frogs lay eggs in water, which hatch into tadpoles that live in the water until they metamorphose into small frogs. The turtle frog doesn’t have that kind of luxury. It doesn’t have a lot of water most of the time, so it hatches into a tiny froglet instead of a tadpole.

The most colorful frogs in the world live in the tropics, especially the poison dart frogs of Central and South America. Poison dart frogs are diurnal, meaning they’re most active during the daytime, and they’re fairly small, with the biggest species growing to no more than about two and a half inches long, or 6 cm. Different species of poison dart frogs are different colors and patterns, ranging from a lovely bright blue to red or yellow. These little frogs need to be brightly colored so that predators know to leave them alone, and the reason they should leave them alone is that poison dart frogs are incredibly toxic.

You may have heard the story that natives of South America would rub the tips of their darts or arrows on these frogs to transfer the frogs’ toxic secretions to the weapons. That’s where the name poison dart frog comes from. That’s sort of true, but not completely true. Not all poison dart frogs were used in this way, just four of the largest species that are especially toxic.

One of these four species is the golden poison dart frog, which lives in the rainforests of Colombia. It’s usually bright yellow with black eyes, although some individuals are a minty green or orange. It looks cheery, but a single frog has enough poison to kill two African elephants, not that it would because it lives in South America and not Africa and the elephants would not try to eat the frog. One frog has enough poison to kill 10 to 20 humans, though, so don’t try to eat one. In fact, don’t even touch it, because poison dart frogs store their poison in skin glands and if a frog feels threatened, it will secrete a tiny amount of the poison. If that poison gets into your body, you will die.

So why do people keep golden poison dart frogs as pets? That would be like having a pet stick of dynamite, right? Actually, it turns out that frogs born in captivity don’t develop the toxins that wild frogs have. Frogs that are captured in the wild and kept in captivity will eventually lose the toxins, although it may take several years. This is because the frog doesn’t manufacture the toxins itself but retains toxins found in some insects it eats, although researchers aren’t sure yet which insect or insects.

The golden poison dart frog lays its eggs on the ground. This sounds weird until you remember that it lives in a rainforest and the ground is covered with dead leaves that are constantly wet from rain. When the eggs hatch into tadpoles, though, they need more than just wet leaves, so the parent frogs squat down and the tadpoles wriggle onto the parents’ backs. They stick there and the parents carry them not to a pond but up into the trees. Water collects in the middle of large leaves of some rainforest tree species, and of course there are always little hollows and holes in tree trunks that can fill with rainwater. The frogs deposit the tadpoles into these little puddles, where the tadpoles eat mosquito larvae and algae. But even then, the parents don’t abandon their babies. Golden poison dart frogs are social animals, not generally a trait you associate with frogs, and they live in little groups of around half a dozen individuals. When the tadpoles finish developing and metamorphose into adult frogs, the parents lead their babies to other golden poison dart frogs so they can join a group.

Finally, our last colorful frog of the episode and the very last animal we’ll cover for 2020 is the tomato frog. As you might have guessed, the tomato frog is red-orange in color. It lives in Madagascar and a big female can grow up to 4 inches long, or 10.5 cm. Males are much smaller and are more yellow than red. But the tomato frog doesn’t use its coloring to hide among tomato plants. Its coloring advertises that it’s toxic, although its toxin is much different from those found in poison dart frogs and not deadly.

The tomato frog mostly eats worms and termites, which it finds by digging around in the leaf litter. It also catches insects with its sticky tongue. It’s not a very good swimmer, surprisingly, and spends most of its time on land or in swampy areas. It’s a mostly nocturnal frog.

If a tomato frog feels threatened, it will puff itself up to appear larger, which also incidentally makes it look even more like a tomato. It will also secrete a sticky white toxin that irritates a predator’s mucus membranes and can cause serious allergic reactions in humans. The toxin is so sticky that it will remain in the predator’s mouth for days. So if you live in Madagascar and have a tomato garden, carefully examine every tomato before you take a bite.

This is what a tomato frog sounds like:

[tomato frog croaking]

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us that way.

Thanks for listening!

Episode 203: Swarms!

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Thanks to Nicholas and Juergen for their suggestions! Let’s learn about some insects that migrate and swarm!

Further listening:

The Animal Migrations Patreon episode (it’s unlocked so anyone can listen)

Further reading:

Ladybugs Are Everywhere!

Monarch butterflies gathered in winter:

The painted lady butterfly:

The bogong moth:

The globe skimmer dragonfly:

Ladybugs spend the winter in bunches, sometimes in your house:

A stink bug, one of many potentially in your house:

This person is not afraid of locusts even though I would be freaking out:

A field in Australia being eaten by locusts (the brown part):

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

Let’s learn about some insects this week, but not just any old insects. Let’s learn about insects that swarm. Thanks to Nicholas and Juergen for suggestions that led to this episode!

Nicholas suggested long-distance migrators ages ago, and I did do an episode about migration for a Patreon episode. I’ve unlocked that episode so anyone can listen to it, with a link in the show notes. I’ve also used some of the information in that episode for this one, specifically the part about monarch butterflies.

In fact, let’s start with the monarch butterfly. The monarch is a good-sized butterfly, with orange and black wings with white spots along the edges and a wingspan of up to four inches, or 10 cm. It lives in many parts of the world, but only the North American subspecies of monarch migrates.

Every autumn, monarch butterflies living in North America, where they breed, head south to winter in the mountains of central Mexico, a trip that can be as long as 3,000 miles, or 4,800 km. They spend the winter in oyamel fir trees, millions of butterflies in the branches. When spring arrives, the butterflies head north again, but they don’t get all the way back to their original range. If they’re lucky, they reach Texas, where they mate and lay eggs on milkweed plants before dying. The caterpillars hatch, eat up the milkweed, spin cocoons, and emerge transformed into new butterflies that continue the flight north, deeper into North America. But those butterflies don’t make it all the way to their parents’ home range either. They too stop to mate, lay eggs, and die. It can take four or five generations for monarch butterflies to reach Canada and other distant parts of North America, and by that time it’s autumn again. The butterflies fly back to Mexico.

Butterflies heading north live out their entire life cycle in only five or six weeks, but the butterflies that return to Mexico live up to eight months. Researchers think the northward migration follows the blooming of milkweed plants. Milkweed contains toxins that make the monarchs poisonous to a lot of animals, but some birds and a lot of insects will eat the caterpillars. Some populations of North American monarchs overwinter in California, Arizona, or Florida instead of Mexico.

The North American monarch is declining in numbers, probably mostly due to the decline of milkweed. The best way to help the butterfly is to plant milkweed in any area you don’t want to mow very often.

While the monarch migration is astounding, it’s not the only butterfly that migrates. A small, pretty butterfly called the painted lady lives throughout much of the world, even the Arctic, but not South America for some reason. Some populations stay put year-round, but some migrate long distances. One population winters in tropical Africa and travels as far as the Arctic Circle during summer, a distance of 4,500 miles, or 7,200 km, which takes six generations. The butterflies who travel back to Africa fly at high altitude, unlike monarch butterflies that fly quite low to the ground most of the time. Unlike the monarch, painted ladies like many kinds of flowers, not just one plant, and they don’t always migrate every year.

In Australia, some populations of the bogong moth migrate some 600 miles, or 965 km. It’s a dark brown moth with a wingspan of up to two inches across, or 5 cm, and naturally enough, it migrates at night. Unlike the butterflies we’ve talked about, the migration doesn’t take successive generations. In spring the moths fly from the lowlands into the mountains, where they spend the summer mostly hiding in caves and other dark places. The bogong moth actually breeds and lays eggs in winter, because it doesn’t like hot weather.

Birds and some other animals depend on the moth migration for food, when they can eat a lot of big fat moths and get lots of protein. Some Aboriginal tribes of southeastern Australia also used to follow the migration into the mountains, where they would gather lots of moths from caves and roast them. Apparently they taste like nuts.

But the insect that migrates farthest is a species of dragonfly. The globe skimmer, also called the wandering glider or winged wanderer, lives in much of the world, but not in Europe. Researchers think it can’t cross the Sahara to reach Europe, but it can cross the Himalayas. It’s the highest-flying dragonfly known as a result. Even though it’s a small dragonfly, less than two inches long, or 4.5 cm, it has big wings, with a wingspan of almost three and a half inches, or 8 and a half cm. Its abdomen is usually yellow, although males are sometimes more reddish. It’s a strong, fast flier and that’s a good thing, because an individual dragonfly may fly as far as 3,700 miles, or 6,000 km, during migration.

Different populations migrate to different areas, naturally, but scientists have compared the genetic profiles of globe skimmers from different parts of the world and discovered that they’re all extremely similar. This can only happen if the dragonflies from different continents are breeding with each other, which suggests that they’re traveling even farther than we already know. The globe skimmer crosses the Indian Ocean between Asia and Africa, and it shows up on incredibly remote islands, so obviously it’s able to cross vast distances without too much trouble.

The reason the globe skimmer migrates is that it needs fresh water to lay its eggs in. Many parts of the world have well-defined rainy seasons and dry seasons, and the globe skimmer wants to stay where it’s rainy. As it travels, it meets up with other dragonflies, mates, and lays eggs as it goes. The eggs develop quickly and the larvae mature within a few weeks, and immediately join the migration.

The reason the globe skimmer is able to migrate is because of its big wings and flying style. Its wings are broad as well as long, which allows it to ride the wind like a surfer riding a wave. It can glide long distances without needing to move its wings, which saves a lot of energy.

But most insects don’t exactly migrate, or at least they only travel relatively short distances to find a place to winter. The ladybug, for instance.

Juergen emailed me a few months ago about meeting one ladybug outside, then going inside to find a bajillion ladybugs. This happens a lot in autumn and it’s amazing how such a pretty little insect can suddenly seem horrifying when there are hundreds or even thousands of them in your home. It happens because many species of ladybug gather together to spend the winter in a sheltered area. Usually the sheltered area is a forest floor or a rock with lots of crannies for them to hide in. But sometimes it’s your house.

The outside of a light-colored house reflects heat from the sun, which is good for your house but which also attracts ladybugs. When a ladybug finds a nice place to spend the winter, it releases pheromones that attract other ladybugs, and before you know it, your house is ladybug central. Even if you bring in an exterminator to get rid of the bugs, the pheromones remain and will continue to attract ladybugs for years. All you can do is make sure ladybugs can’t get into your house by sealing up every little crack and gap. If the ladybugs do remain, a lot of them will probably die because most houses are too dry for them in winter. The ones that do survive will leave in spring, and at least they don’t eat anything while they’re hibernating. Ladybugs eat aphids and other plant pests during warmer months, so they’re helpful to gardeners and farmers. There are special traps you can get that attract ladybugs and hold them inside until you take them out and release them.

Another insect, commonly called the stinkbug for the nasty odor it releases if it feels threatened, also called the shield bug for its shape, also sometimes comes into houses to spend the winter, sometimes in huge numbers. The most common species in North America these days is the brown marmorated stinkbug, which is a mottled brown with small black and white markings to help it blend in with tree bark. It can grow up to three-quarters of an inch long, or two cm, and is big and heavy and a very clumsy flyer.

The brown marmorated stinkbug is an invasive species from Asia that arrived in North America in the 1990s and has spread throughout the continent, especially the eastern United States. It eats plants and can destroy fruit crops and other crops like beans and tomatoes. So unlike the ladybug, it’s not a beneficial insect to humans. But despite its bad smell, it’s not dangerous to humans or pets. The stinkbug will often appear in your house in fall but also in spring, when it emerges from its little hiding spot in your house and tries to find its way outside.

Finally, let’s look at an infamous swarming insect, the locust. Locusts are responsible for untold thousands of humans dying of starvation when clouds of them sweep through a location, eat up every scrap of food they can find, and move on when all the food is gone. But what are locusts, and why do they do this?

The locust is a type of grasshopper. Specifically, it’s one of several species of short-horned grasshoppers. Ordinarily the grasshoppers are no different from other grasshoppers. But occasionally there’s a drought where a population of the grasshoppers live, and after the drought is over and the plants that died back start to grow really fast, the grasshoppers change.

First, the grasshoppers start to breed much more than usual. When those eggs hatch, the nymphs, which is what baby grasshoppers are called, stay together in groups instead of dispersing and start moving together. They don’t have wings until they grow up so they just hop together and meet up with more and more nymphs. Once they metamorphose into adult grasshoppers, they’re called locusts although they’re still the same grasshoppers as before, just with different behaviors. Some species also look a little different during swarming seasons, often larger than usual and sometimes with different coloration or markings.

Many of these species of grasshopper are large, up to four and a half inches long, or 11 cm, with large wings that make them strong fliers. The swarms can fly up to 93 miles a day, or 150 km, and land when they find a lot of food, which may be crops planted by humans. After the swarm has eaten everything it can find, it moves on to find more. It also leaves behind lots of eggs that soon hatch into new grasshopper nymphs that eat anything that’s started growing again.

If you’re wondering how even a whole bunch of grasshoppers can cause people to starve to death, you don’t have an idea yet of the size of the swarms. Locust swarms can contain tens of billions of grasshoppers. That’s billion with a B. An individual swarm can easily cover more than 100 square miles, or 260 square km, and when they land, they will literally eat every growing plant down to the ground, every single leaf, every single blade of grass, everything. Not only is there nothing left of crops when a locust swarm has come through, there’s no grass or leaves for animals to eat.

The largest locust swarm that we know of was seen in 1875 in the western United States. The swarm covered an estimated 198,000 square miles, or 510,000 square km. That’s larger than the entire state of California. There may have been over 12 trillion individual grasshoppers in that swarm.

This was the Rocky Mountain locust, which was adapted to the prairies of North America. As white settlers pushed west and planted crops where there had formerly only been prairie grass and other prairie plants, the farmers were repeatedly visited by locusts that ate not just their crops, but everything else they could find. The locusts ate leather, wool, wood, and there are even reports of locusts eating the clothes people were actually wearing. There were so many locusts that they couldn’t be avoided. They would get into houses and eat up food in the pantries, along with blankets and clothing. People tried everything they could think of to destroy the locusts, from setting entire fields on fire to building horse-drawn bulldozers that smashed the locusts flat. But nothing helped. There were too many of them.

But as the years passed and more and more prairie was converted to fields or pastures for cattle, and more cities and towns grew up in the west, the Rocky Mountain locust started to decline in numbers. In 2014 it was declared extinct, but by then no one had seen a Rocky Mountain locust since 1902. It’s possible they’re still around in small numbers, but a combination of habitat loss and active eradication of the insect probably drove it to extinction. Another species of North American grasshopper, the high plains locust, is rare these days and almost never swarms, with the last big swarm reported in the 1930s.

But there are plenty of other locusts throughout the world, reported throughout recorded history, including the ancient Egyptians, ancient Greeks, and ancient Chinese. Plagues of locusts feature in the Quran and the Bible. The most well known species are the desert locust, which lives in Africa and parts of the Middle East and Asia, and the migratory locust, which lives in Africa, Asia, Australia, New Zealand, and Europe, although it’s quite rare in Europe these days.

Not all locust swarms are enormous, of course, but even a small swarm can destroy local farms and pastures. In the days before easy communication and travel, this could mean people starved in one village even if the next village over was fine. Researchers estimate that a locust swarm that’s only one square kilometer in size, which is less than half a square mile, or about 250 acres, can eat as much as 35,000 people in a single day. WHOA, I did not realize when I wrote that that it would make it sound like the locusts were eating people. Locusts don’t eat people, they don’t hurt you, but the locusts eat as much food as 35,000 people do. That’s what I meant.

The thought of locust swarms is scary, but fortunately it doesn’t happen every year or even every decade. But it does still happen. In 1988, locusts swarming in Africa crossed the Atlantic Ocean and arrived in South America. This year, 2020, started out with desert locusts swarming in parts of north and east Africa in January, spreading into parts of Asia by May. In November, some localized swarms of locusts were spotted in parts of Australia after heavy rains, especially in west and northwest Victoria.

These days, though, people have the advantage of early warning. Locust swarms can be tracked by satellite and drones, people whose crops are eaten up can have food shipped in to help keep anyone from starving, and there are pesticides that can kill a lot of locusts in a short amount of time. But a new experimental biological control has been working really well. The dried spores of a fungus that kills grasshoppers are sprayed on the ground where locusts are laying eggs, since grasshoppers lay their eggs in soil or sand. The fungus kills the grasshoppers and stays on the ground to kill the ones that hatch or arrive later. Best of all, unlike chemical pesticides, the fungus doesn’t kill other insects.

And don’t forget, of course, that the locust is edible. Cultures throughout much of the world traditionally ate locusts and they’re still considered delicacies in many places. They’re also more nutritious than meat from mammals like cattle. Besides, if locusts arrive and eat all your food, it’s just smart to eat the locusts that ate your food. You gotta get that food back somehow.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us that way.

Thanks for listening!

Episode 202: Terror Birds and Pseudotooth Birds

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Let’s find out about some gigantic birds this week! Thanks to Pranav and Richard for the suggestions!

Further reading:

Exceptionally preserved fossil gives voice to ancient terror bird

Antarctica yields oldest fossils of giant birds with 21-foot wingspans

Look at that beak! Llallawavis scagliai:

Big birdie!

A red-legged seriema and an unfortunate snake:

Another big birdie!

Toothy birdie!

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we’re going to learn about some gigantic extinct birds! Pranav wants to hear about Phorusrhacidae, also known as the terror bird. Something called a terror bird is definitely going to be interesting. My brother Richard also tweeted me about some huge extinct birds called pelagornithids, so we’ll talk about them too. Both birds were huge and successful, but extremely different from each other.

Phorusrhacidae is the name for a family of flightless birds that lived from about 62 million years ago to a little under 2 million years ago. Flightless birds may make you think of ostriches and penguins and dodos, but remember that Phorusrhacids were called terror birds. They were carnivores and many of them were enormous.

Most terror birds lived in South America, with one species known from southern North America. A few newly discovered bird fossils from Africa and Europe may have been close relations of terror birds, but palaeontologists are still studying them.

Various species of terror bird ranged in size from about 3 feet tall to 10 feet tall, or 1 to 3 meters, and had long, strong legs that made them fast runners. The terror bird also had a long, strong neck, a sharp hooked beak, and sharp talons on its toes. The beak was strong but the jaw muscles were relatively weak. Researchers think that it ambushed prey and chased it down, then either kicked it to death with its sharp talons or held it down with its feet and stabbed it to death with its beak. Smaller species may have grabbed its prey and thrown it back down with enough force to injure, stun, or outright kill the animal. It may have swallowed small prey whole and regurgitated pellets made up of compressed fur and bones, the way many modern carnivorous birds do today.

Although the beak was strong, it was also hollow. This would have made it weigh less, which meant that the bird could move its head more quickly. Some researchers think that it might also have acted as a resonant chamber, and that the bird could clap its beak closed to make a loud noise to communicate with other terror birds. It had excellent hearing and vision, but a poor sense of smell.

Many details of what we know about terror birds come from a single specimen discovered in 2010 in Argentina. The bird lived around 3 million years ago and stood four feet tall, or 1.2 meters. It was described in 2015 and is named Scaglia’s magnificent bird. I am not going to attempt to pronounce its scientific name [Llallawavis scagliai], but I’ll put it in the show notes along with a picture. Almost the entire skeleton is preserved in stunning detail, including details that hardly ever preserve, like the tiny bones that help the eye focus. Studies of the tiny ear bones and other details of the ear indicate that its hearing was most acute at low frequencies, which meant it would have been good at hearing footsteps. It also probably had a deep voice.

The terror bird had wings, but they were small and probably only used for display. The wings did have claws, though, and may have been used to fight other terror birds over mates or territory. Young terror birds of some species might have been able to fly, although adults certainly couldn’t.

The earliest known terror bird, Paleopsilopterus, lived about 60 million years ago in what is now Brazil. It was relatively small, only about three feet high, or 1 meter. It evolved only a few million years after the non-avian dinosaurs went extinct, and its descendants became larger and more fearsome until they were apex predators throughout South America.

Kelenken, for instance, grew up to ten feet tall, or three meters, and had an enormous beak, 18 inches long or almost 46 cm. It lived in what is now Argentina around 15 mya. It’s the tallest terror bird known but it was more slenderly built than others so was probably a faster runner. It was only discovered in 1999.

Brontornis, however, was the one that puts the terror into terror bird. It grew over 9 feet tall, or 2.8 meters, but it was massively built. It probably wasn’t a very fast runner and would have definitely been an ambush predator. Most likely it hid among trees or other tall vegetation, and when an animal came too close, BOOM! THERE’S A TERROR BIRD! RUN! TOO LATE, ARGH!

Titanis lived in parts of North America, with fossils found in Texas and Florida. It probably stood a little over eight feet tall, or 2.5 meters, although we don’t have any complete skeletons so can only estimate its actual size compared to other species of terror bird. You may find information online that says Titanis lived as recently as 10,000 years ago in Florida, and that it used the claws on its wings like hands to help catch prey. Both these things are wrong, unfortunately. The fossil bones found in the Santa Fe River in Florida had washed out of their original location and were mixed in with much more recent bones, and there’s no evidence that any terror bird used its wings like hands. Terror birds were descended from birds that could fly, not descended directly from dinosaurs, so its wings were still highly modified for flight.

Titanis lived in North America about five million years ago. But how did it get to North America from South America before the Isthmus of Panama formed around three million years ago? Before then, a big stretch of ocean separated the two continents. Researchers think it island-hopped, as the tops of mountains and hills in what is now Central America first emerged from the ocean as sea levels dropped, forming islands. Volcanoes also formed islands in the area. Titanis may have traveled to these islands by swimming or rafting during storms.

Terror birds went extinct after the Isthmus of Panama opened up when sea levels lowered. This connected North and South America, which allowed animals from North America to cross into South America and vice versa. The Andes Mountains also formed about this time and changed the climate of much of South America. Forests became open savanna where terror birds wouldn’t have been able to hide to ambush prey. Climate change combined with increased competition from saber-toothed cats and other North American predators probably led to the terror birds’ extinction.

There are no descendants of terror birds living today, but its closest living relations are probably the seriema birds, the red-legged and the black-legged seriema. Both live in South America and both are carnivorous birds that eat small animals like rodents, lizards, snakes, and even other birds. When it catches an animal, it beats it against the ground until it dies. It will also sometimes eat fruit and eggs.

The red-legged seriema stands a little over three feet tall, or a meter, with long legs, long neck, and long tail. It’s mostly brown and gray and it has a fan-shaped crest low down on its forehead, just above the bill. The gray-legged seriema looks very similar but is mostly gray. The seriema also has a sickle claw on each foot that it uses to cut pieces off its dead prey so it can swallow them more easily.

The seriema can fly, but it prefers to walk or run. It can run up to 15 mph, or 25 km/h. It builds its nest in low bushes so it can just hop up onto the nest instead of having to fly. It’s also aggressive and will attack animals much larger than it is, driving them away from its nest or chicks. Farmers sometimes catch young seriemas and tame them, then allow them to patrol the farmyard to catch rats and snakes and drive away larger predators.

Next, let’s learn about a different giant extinct bird, Richard’s suggestion. Unlike the terror bird, pelagornithids could fly. They’re sometimes called pseudotooth birds because they had teeth, but they weren’t real teeth. They were pointy projections of the jaw bones that grew along the edges of its beak and were covered with keratin. Pelagornithids evolved around the same time as the terror bird, around 62 million years ago, and didn’t die out until about the same time as the terror bird, around 2.5 million years ago.

And like the terror bird, pelagornithids were huge, but in a different way than terror birds. They were sea birds that may have superficially resembled modern albatrosses, but they were much larger. The largest living albatross has a wingspan of about 11 1/2 feet, or 3.5 meters, but the largest known pelagornithid had a wingspan estimated at up to 21 feet, or almost 6.5 meters. Its wings were narrow and pointed like albatross wings are.

Researchers think that the pelagornithid probably mostly ate soft-bodied animals like squid and other cephalopods, because its teeth were not very strong. It probably scooped its prey up from the water while flying, like many modern seabirds do, although it could probably also sit on the water and dip its long, strong beak down to catch anything that swam too close. Its bones were too delicate for diving. It may have had a throat sac like a pelican too. It was probably white or gray in color and its wings and tail were probably black, which is the most common coloration for sea birds of any kind.

It had short legs but enormously long wings, so long that it probably couldn’t flap them. Its strongest muscles were the ones that held the wings out straight. It was definitely a bird, of course, but it was proportioned more like a flying reptile, Pteranodon, even though they weren’t related. You know what that means, of course. Convergent evolution! Researchers think the pelagornithid spent almost all its time soaring on ocean breezes, scooping up cephalopods and fish to swallow whole, and that Pteranodon probably did the same. These days, modern albatrosses fill that particular ecological niche, and the albatross has many similarities to the pelagornithid too.

Pelagornithids of various species were found throughout the world, from the Arctic and Antarctic to the tropics. It was extremely successful and unlike the terror bird, which was restricted to land, it could travel as far as it liked as long as it had a breeze to keep it aloft. It evolved soon after the non-avian dinosaurs went extinct and didn’t die out until the beginning of the Pleistocene. What happened then? Why aren’t these enormous birds still flying around?

The Pleistocene, of course, was the ice age, or more properly the ice ages. Its onset resulted from a lot of factors, including the movement of continents that changed ocean currents radically. Once the changes started, they accelerated quickly. As more water froze and became massive glaciers that weighted down entire continents, sea levels dropped and more land was exposed, including the Isthmus of Panama that connected North and South America. This would have radically changed the air currents that pelagornithids used to travel around the world, from nesting sites to feeding sites and back. It also drove many sea animals to extinction as their environments became too cold or too warm for them to adapt to, or the water where they lived just dried up completely.

The one place where pelagornithids couldn’t go was across continents. They needed constant sea breezes and lots of water where they could catch prey, and steep cliffs near water to nest on. As the ecological changes of the Pleistocene became more pronounced, pelagornithids had more and more trouble surviving, and finally they went extinct. Modern albatrosses, gulls, and cormorants expanded at the same time to fill the ecological niche left open by the pelagornithid.

While there are no living descendants of pelagornithids, researchers tentatively think they’re most closely related to living ducks, geese, and swans. Since most pelagornithid fossils are badly damaged and fragmented, so that we only have one or two bones preserved from any given animal, it’s hard for scientists to make conclusions as to what they were most closely related to. Hopefully more and better fossils will be found soon so we can learn more about these gigantic birds!

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us and get twice-monthly bonus episodes for as little as one dollar a month.

Thanks for listening!

Episode 201: The African Grey Parrot and More Mantises

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This week we’ll learn about a fascinating parrot and some more weird praying mantises! Thanks to Page and Viola for the suggestions!

Further watching:

Nova Science Now: Irene Pepperberg and Alex

Alex: Number Comprehension by a Grey Parrot

The Smartest Parrots in the World

Further reading:

Why Do Parrots Talk?

Ancient mantis-man petroglyph discovered in Iran

Alex and Irene Pepperberg (photo taken from the “Why do parrots talk?” article above):

Two African grey parrots:

The “mantis man” petroglyph:

The conehead mantis is even weirder than “ordinary” mantis species:

Where does Empusa fasciata begin and the flower end (photo by Mehmet Karaca)?

The beautiful spiny flower mantis:

The ghost mantis looks not like a ghost but a dead leaf:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we’re going to look at two completely unrelated animals, but both are really interesting. Thanks to Page and Viola for the suggestions!

We’ll start with Page’s suggestion, the African gray parrot. We haven’t talked about very many parrots in previous episodes, even though parrots are awesome. The African gray parrot is from Africa, and it’s mostly gray, and it is a parrot. Specifically it’s from what’s called equatorial Africa, which means it lives in the middle of the continent nearest the equator, in rainforests. It has a wingspan of up to 20 inches, or 52 cm, and it has red tail feathers.

The African gray parrot is a popular pet because it’s really good at learning how to talk. It doesn’t just imitate speech, it imitates various noises it hears too. It’s also one of the most intelligent parrots known. Some studies indicate it may have the same cognitive abilities as a five year old child, including the ability to do simple addition. It will also give its treats to other parrots it likes even if it has to go without a treat as a result, and it will share food with other parrots it doesn’t even know.

Despite all the studies about the African grey in captivity, we don’t know much about it in the wild. Like other parrots, it’s a highly social bird. It mostly eats fruit, seeds, and nuts, but will also eat some insects, snails, flowers, and other plant parts. It mates for life and builds its nest in a tree cavity. Both parents help feed the babies. That’s basically all we know.

It’s endangered in the wild due to habitat loss, hunting, and capture for sale as pets, so if you want to adopt an African grey parrot, make sure you buy from a reputable parrot breeder who doesn’t buy wild birds. For every wild parrot that’s sold as a pet, probably a dozen died after being taken from the wild. A good breeder will also only sell healthy birds, and will make sure you understand how to properly take care of a parrot. Since the African grey can live to be up to sixty years old, ideally it will be your buddy for basically the rest of your life, but it will require a lot of interaction and care to stay happy and healthy.

One African grey parrot named Alex was famous for his ability to speak. Animal psychologist Dr. Irene Pepperberg bought Alex at a pet shop in 1977 when he was about one year old, not just because she thought parrots were neat and wanted a pet parrot, but because she wanted to study language ability in parrots.

Pepperberg taught Alex to speak and to perform simple tasks to assess his cognitive abilities. Back then, scientists didn’t realize parrots and other birds were intelligent. They thought an animal needed a specific set of traits to display intelligence, such as a big brain and hands. You know, things that humans and apes have, but most animals don’t. Pepperberg’s studies of Alex and other parrots proved that intelligence isn’t limited to animals that are similar to us.

Alex had a vocabulary of about 100 words, which is average for a parrot, but instead of just mimicking sounds, he seemed to understand what the words meant. He even combined words in new ways. He combined the words banana and cherry into the word banerry to describe an apple. He didn’t know the word for cake, so when someone brought a birthday cake into the lab and he got to taste it, he called it yummy bread. When he saw himself in a mirror for the first time, he said, “What color?” because he didn’t know the word gray. He also asked questions about new items he saw. So not only did he understand what words meant, he actually used them to communicate with humans. As Pepperberg explains, Alex wasn’t super-intelligent or unusual for a parrot. He was just an ordinary parrot, but was trained properly so he could express in words the intelligence that an average parrot uses every day to find food and live in a social environment.

Alex died unexpectedly in 2007 at only 31 years old. I’ve put a link in the show notes to a really lovely Nova Science Now segment about Alex and Dr. Pepperberg, and some other videos of Alex and other parrots. Pepperberg has continued to work with other parrots to continue her studies of language and intelligence in birds.

This is audio of Alex speaking with Pepperberg. You’ll notice that he sounds like a parrot version of her, which is natural since he learned to speak by mimicking her voice, meaning they have the same intonations and pronunciations.

[Alex the parrot speaking with his trainer, Dr. Pepperberg]

Next, Viola wants to learn about praying mantises. We had an episode about them not too long ago, episode 187, but there are more than 2,400 known species, so many that we could have hundreds of praying mantis episodes without running out of new ones to talk about.

Today we’ll start somewhere I bet you didn’t expect, an ancient rock carving from central Iran.

The carving was discovered while archaeologists were surveying the region in 2017 and 2018. I’ll put a picture of it in the show notes, but when you first look at it, you might think it was a drawing of a plant or just a decoration. I’ll try to describe it. There’s a central line that goes up and down like a stick, with three lines crossing the central line and a rounded triangle near the top. The three lines have decorations on each end too. The bottom line curls downward at the ends, the middle line ends in a little circle at each end, and the top line curves up and then down again at the ends. It’s 5 1/2 inches tall, or 14 cm, and a little over four inches across at the widest, or 11 cm. Archaeologists have estimated its age as somewhere between 4,000 years old and 40,000 years old. Hopefully they’ll be able to narrow this age range down further in the future.

The team that found the carving, which is properly called a petroglyph, was actually looking specifically for petroglyphs that represented invertebrates. So instead of thinking, “Oh, that’s just a tree” or “I don’t know what that is, therefore it must just be a random doodle,” the archaeologists thought, “Bingo, we have a six-legged figure with a triangular head and front legs that form hooks. It looks a lot like some kind of praying mantis.”

But while archaeologists might know a lot about petroglyphs, they’re not experts about insects, so the archaeologists asked some entomologists for help. They wanted to know what kind of praying mantis the carving might depict.

The entomologists thought it looked most like a mantis in the genus Empusa, and several species of Empusa live in or near the area, although they’re more common in Africa. So let’s talk about a few Empusa species first.

The conehead mantis is in the genus Empusa and is native to parts of northern Africa and southern Europe. Like most mantises, females are larger than males, and a big female conehead mantis can grow up to four inches long, or 10 cm. The body is thin and sticklike, with long, thin legs, and individuals may be green, brown, or pink to blend in among the shrubs and other low-growing plants where it lives. It eats insects, especially flies. So far this is all pretty normal for a praying mantis. But the conehead mantis has a projection at the back of the head that sticks almost straight up. It’s called a crown extension and it helps camouflage it among sticks and twigs. It also often carries its abdomen so that it curves upward.

Other members of the genus Empusa share these weird characteristics with the conehead mantis. Empusa fasciata lives in parts of western Asia to northeastern Italy and is usually green and pink with lobe-shaped projections on its legs that help it blend in with leaves and flowers. It mostly eats bees and flies, and females spend a lot of time waiting on flowers for a bee to visit. And then you know what it does…CHOMP. The more I learn about insects that live on flowers, the more I sympathize with bees. Everything wants to eat bees. E. fasciata also has a crown extension that makes its head look like a knob on a twig, and it also sometimes carries its abdomen curved sharply upward so that it looks a lot like a little spray of flowers.

Most mantids are well camouflaged. We talked about the orchid mantis in episode 187, which mimics flowers the same way E. fasciata does. But a few mantis species look like they should really stand out instead of blending in, at least to human sensibilities. The spiny flower mantis is white with green or orange stripes on its legs and a circular green, yellow, and black pattern on its wings. When I first saw a photo of it, I honestly thought someone had photoshopped the wing pattern on. But if something threatens a spiny flower mantis, it opens its wings in a threat display, and the swirling circular pattern suddenly looks like two big eyes. It also honestly looks like really nifty modern art. I really like this mantis, and you know I am not fond of insects so that’s saying something. It lives in sub-Saharan Africa and females grow about two inches long, or 5 cm.

Finally, the ghost mantis is really not very well named because it doesn’t look anything like a ghost, unless a ghost looks like a dead leaf. It looks so much like a leaf that it should be called a leaf mantis, but there are actually lots of different species called leaf mantis or dead leaf mantis. This particular one is Phyllocrania paradoxa, and it also grows to about two inches long, or 5 cm. It lives in Africa and most individuals are brown, although some are green or tan depending on the humidity level where it lives. It looks exactly like a dead leaf that’s sort of curled up, except that this leaf has legs and eats moths and flies. It even has a crown extension that looks like the stem of a leaf. Unlike most mantis species, it’s actually pretty timid and less aggressive toward members of its own species. In other words, ghost mantises are less likely to eat each other than most mantis species are.

People keep all these mantises as pets, which I personally think is weird but that’s fine. They’re easier to take care of than parrots are, although you’ll never manage to teach a praying mantis to talk.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us that way.

Thanks for listening!