Tag Archives: butterflies

Episode 203: Swarms!

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!

BONUS! All about animal poop


A dung beetle rolling some poop:

Butterflies on poop:

Wombat poop is cubes!

Show transcript:

Welcome to a bonus episode made out of a bonus episode. Since this week’s topic is one that some adults may decide they don’t want their young kids listening to, because it goes into detail about hyena reproduction, I decided to unlock a Patreon bonus episode for everyone to listen to. But then I decided to actually release that episode so that listeners can download it normally in the main feed. Those of you who want time to pre-screen the hyena episode to see if it’s appropriate for your kids to listen to can listen to this episode together in the meantime, and those of you who decide the hyena episode isn’t right for your kiddos still have an episode this week as usual. The rest of you get two episodes this week! A special thanks to our Patreon subscribers who support the show and get twice-monthly bonus episodes like this one every single month. This is the only part of the episode that is new; the rest was originally recorded in late 2018. And here it is!

The topic for today’s episode was suggested by my aunt Janice. Janice doesn’t actually listen to the podcast, not even the main feed podcast, but she sends me topic suggestions every so often. Recently, she texted me out of the blue, saying, “I’ve decided that you need to do a podcast devoted to the topic of animal poop. Butterflies eat it, dung beetles roll it, owls leave pellets with tiny animal bones, guano has commercial uses, people make no-bake chocolate and peanut butter cookies and call them cow pie cookies. Goats are gumball machines! Why are so many animals’ poops little Raisinets, but others are long thick Tootsie rolls? Why do so many animals eat poop?” Only, she didn’t say poop. She said another word.

Then I texted her back, telling her how wombat poop is actually little cubes, which blew her mind.

If you listened to the spookiest owl episode recently in the main feed, you may remember about owl pellets. Those do indeed contain bones and other indigestible parts of the owl’s prey, like fur or feathers, but the pellets themselves aren’t the same thing as poops.

Poop, or more properly excrement or feces, is what’s left after food passes through an animal’s digestive system. It contains not just the remains of food that wasn’t fully digested, but secretions from the digestive system, bacteria that live in the digestive system, and of course water. The secretions include a chemical called stercobilin, which helps the body digest fat, and which is what makes your poop brown. Yes, I googled what poop is made up of. I googled it so you wouldn’t have to. I didn’t want to know this stuff. You’re welcome.

Incidentally, the bacteria in your digestive system actually help your digestion and do other good things for your body. People who have to take strong antibiotics or radiation treatment sometimes have trouble with their digestion because the antibiotics or radiation can accidentally kill a lot of the beneficial bacteria in the digestive system. Getting the bacteria back in such cases is simple, usually taking a doctor-prescribed supplement of probiotics, or in less acute cases, just eating a lot of yogurt or certain other foods, like sauerkraut or kimchi, which naturally contain probiotics.

Humans aren’t the only animals with beneficial bacteria in the digestive system. In fact, all animals have them. Some young animals, including horses, will eat their mother’s poop to gain digestive bacteria. Personally, I prefer yogurt.

Oh, and you know how dogs like to get into the cat’s litter tray and eat the cat poop? That’s because cats are obligate carnivores, which means they have to eat meat for almost all of their nutritional needs. That means cat poop is relatively high in protein, which makes it attractive to dogs. I can’t believe I’m talking about this. I hope you’re not snacking while you listen.

I’m sure a lot of us have seen butterflies gathered together on a hiking trail or in a pasture, their wings fluttering in the sunlight, and when you get too close they all fly up together and swirl around, making you smile and think about how wonderful it is that you live in a world with butterflies. Then you look at what the butterflies were gathered on, and it’s an animal poop. Why do they do that?

While butterflies do eat nectar, nectar doesn’t contain all the nutrients they need. It especially doesn’t contain much sodium—you know, salt. So butterflies get sodium and other nutrients from rotting fruit, rotting meat, and animal dung. Also, if a butterfly has ever landed on you, it was probably attracted to your sweat, which contains salt. A lot of times, male butterflies will collect nutrients from poop and other sources and offer them to the female as a gift, hoping she’ll choose him as her mate. I personally would rather have chocolate, but I’m not a butterfly.

Moths also eat poop and other unsavory things, but some moths will cut out the middle-man, so to speak, and actually drink blood from living animals. Vampire moths mostly feed on fruit, piercing the fruit with their mouthparts to suck out the juice. But they’ll also use those same mouthparts to pierce animal skin and drink blood. Most vampire moths live in Asia and parts of southern Europe, but there is a species that lives in North America, although it hasn’t been observed drinking blood. Only male vampire moths eat blood, probably mostly for its salt content, which researchers think they pass along to the female during mating.

The size and shape of an animal’s dung depends on what it eats, how it digests its food, and the size and shape of its colon. Ruminants, like cows, evolved in areas where there was a lot of water, so their feces contain a lot of water. Ungulates, like sheep, goats, and deer, evolved in dryer conditions, so as much water is removed from the feces as possible and the animal excretes dry pellets.

But what about wombat poop? It really is shaped like little cubes, and it excretes 80 to 100 of the cubes every night, since it’s nocturnal. Why is it cube-shaped?

Wombats are territorial, and mark their territory by leaving their poop around their burrows and in areas where other wombats can easily find it. This includes on top of rocks and fallen logs, so having dung that won’t roll off these markers is beneficial for the wombat. The shape is caused by the wombat’s extremely long digestive process. It takes more than two weeks to digest the plants it eats, which allows it to absorb as much water and nutrients as possible. The upper part of its large intestine contains ridges that shape the excrement as it passes through, and the poop is so compacted from its long trip through the digestive system, that it retains its shape until it’s deposited where the wombat wants to leave it.

There are a number of different kinds of dung beetles throughout the world, and not all of them roll dung, but they all eat it. The dung beetles that roll poop are mostly those in the genus Scarabaeus. While poop-eating insects sound disgusting, they’re actually quite beneficial. Some species of dung beetles will bury the poop and lay eggs in it, which fertilizes the soil and helps disperse seeds that may be in the poop, and controls parasites. At least one dung beetle, Scarabaeus satyrus, rolls its dung balls quite a distance, and navigates by the stars and the Milky Way.

Guano is the term for both bat poop and sea bird poop, and it does indeed have commercial uses. It contains high levels of nitrogen, phosphate, and potassium, all of which are good for plants, so it’s used as a fertilizer. It also acts as a natural fungicide for plants. Bat guano was also once mined from caves to make gunpowder, which requires saltpeter, or potassium nitrate, which bat guano is full of.

The Thai Elephant Conservation Center, which you may remember from episode 23, non-human musicians, has developed a way to turn elephant dung into paper, which they then make into handmade notebooks. Since an elephant’s poop is mostly fiber from the plants it eats, and paper is made from plant fibers, it all makes sense. Don’t worry, the fibers are boiled to sterilize them before being used. Other companies have started using animal poop to make artisanal paper, including from pandas and sheep.

Scientists can learn a lot about an animal by studying its poop. Not only can a researcher get an idea of how healthy an animal is, they can learn what an animal is eating, what parasites it may have, and its reproductive cycle, since hormones are excreted with the poop too. Gathering poop doesn’t hurt the animal, and isn’t dangerous for the researcher, since they just pick it up off the ground. In zoos and other places where the animals are fed, researchers can mix additives in an individual animal’s food that help them identify which poop came from that animal. Additives include food dyes and glitter.

I think we’ve touched on everything my aunt Janice mentioned in her suggestion, except for cow pie cookies. I have no idea why people make them and call them that. That’s gross. Once I went to an office birthday party where the cake was made to look like it was made of poop. It was so realistic and disgusting-looking that half the office wouldn’t even try a piece. I don’t remember if I had any. Probably, knowing me. It was chocolate, after all.

Thanks for your support, and thanks for listening!

Episode 185: Ice Worms, Army Ants, and Other Strange Invertebrates!

Let’s learn about some weird insects this week! Thanks to Llewelly for suggesting army ants!

Further reading:

If you’re interested in the magazine Flying Snake, I recommend it! You can order online or print issues by emailing the editor, Richard Muirhead, at the address on the website, and there’s a collection of the first five issues on Amazon here (in the U.S.) or here (UK)!

The magnificent, tiny ice worm! The dark speckles in the snow (left) are dozens of ice worms, and the ones on the right are shown next to a penny for scale. Teeny!

ARMY ANTS! WATCH OUT. These are soldier ants from various species:

The Appalachian tiger swallowtail (dark version of the female on the right):

Tiger swallowtails compared:

The giant whip scorpion. Not baby:

Jerusalem cricket. Also not baby but more baby than whip scorpion:


Show transcript:

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

This week we’re going to talk about a number of strange and interesting invertebrates as part of Invertebrate August. Thanks to Llewelly for a great suggestion, and we also have a mystery invertebrate that I learned about from the awesome magazine Flying Snake. Flying Snake is a small UK magazine about strange animals and weird things that happen around the world. It’s a lot of fun and I’ll put a link in the show notes if you want to learn more about it. It’s been published for years and years but I only just learned about it a few months ago, and promptly ordered paper copies of all the issues, but they’re also available online and the first five issues are collected into a book.

So, let’s start with an invertebrate I only just learned about, and which I was so fascinated by I wanted to tell you all about it immediately! It’s called the ice worm, and it’s so weird that it sounds like something totally made up! But not only is it real, there are at least 77 species that live in northern North America, specifically parts of Alaska, Washington state, Oregon, and British Columbia.

The ice worm is related to the earthworm, and in fact it looks like a dark-colored, tiny earthworm if you look closely. It’s usually black or dark brown. It likes the cold—in fact, it requires a temperature of around 32 degrees Fahrenheit, or zero Celsius, to survive. You know, freezing. But the ice worm doesn’t freeze. In fact, if it gets much warmer than freezing, it will die. Some species live in snow and among the gravel in streambeds, and some actually live in glaciers. Ice worms can survive and thrive in such cold conditions because their body contains proteins that act as a natural antifreeze. It navigates through densely packed ice crystals with the help of tiny bristles called setae [see-tee] that help it grip the crystals. Earthworms have setae too to help them move through soil.

During the day, the ice worm hides in snow or ice to avoid the sun, and comes to the surface from the late afternoon through morning. It will also come to the surface on cloudy or foggy days. It eats pollen that gets trapped in snow and algae that is specialized to live in snow and ice, as well as bacteria and other microscopic or nearly microscopic animals and plant material. In turn, lots of birds eat ice worms. Birds also occasionally carry ice worms from one glacier or mountaintop to another by accident, which is how ice worms have spread to different areas.

The glacier ice worm can grow to 15 mm long and is only half a mm thick, basically just a little thread of a worm. It only lives in glaciers. You’d think that in such an extreme environment there would only be small pockets of glacier ice worms, but researchers in 2002 estimated that the Suiattle [soo-attle] Glacier in Washington state contained 7 billion ice worms. That’s Billion with a B on one single glacier. Other ice worm species can grow longer than the glacier ice worm, including Harriman’s ice worm that can grow nearly 2.5 inches long, or 6 cm, and is 2.5 mm thick.

There are tall tales about ice worms that can grow 50 feet long, or 15 meters, but those are just stories. An ice worm that big wouldn’t be able to find enough to eat.

Next, let’s talk about a type of ant. Llewelly suggested the army ant a long time ago, and recently I got an email from Ivy whose list of favorite animals includes the army ant!

The army ant lives in parts of Africa, South America, and Asia, and although there are some 200 species in different subfamilies, recent research suggests that many of them are descended from the same species that lived in the supercontinent Gondwana more than 100 million years ago.

Army ants don’t dig permanent nests like other ants. Instead they make temporary camps, usually in a tree trunk or sometimes in a burrow the ants dig. But these camps aren’t anything like ordinary ant nests. Often they’re formed from the bodies of worker ants, who link their legs together to make a living wall. The walls form tubes that make up chambers and passages of the nest, and inside the nest the queen lays her eggs. There are also chambers where food is stored. But the nest isn’t permanent. At most, the army ant only stays in one place for a few weeks, after the larvae pupate. The colony feeds the food stores to the queen, who lays a new batch of eggs timed to hatch when the new ants emerge from their cocoons. At that point, the colony breaks camp and enters the nomadic phase of behavior until the newly hatched batch of larvae are ready to pupate.

What do they do with the larvae while they wander? Workers carry them around. As in other ant species and the honeybees we talked about recently, an army ant colony is divided into different types of ant. There’s a single queen ant, seasonally hatched males with wings who fly off as soon as they’re grown, and many worker ants. But army ants have another caste, the soldier ant. These are much larger than the worker ants and have big heads and strong, sharp mandibles. Some species of army ant forage primarily on the ground while some hunt through treetops and some underground, but they generally hunt in large, well-organized columns with soldier ants on the outside as guards. In many species, the worker ants are further divided into castes that are specialized for specific tasks.

The queen ant is an egg-laying machine. Queens of some species can lay up to 4 million eggs every month. The queen is wingless, but a new queen doesn’t need to leave the colony the way other ant species do. Instead, when new queens emerge from their cocoons as adults, the colony splits and two new colonies form from the old one, each with one of the new queens. Usually more than two queens hatch, but only two survive.

When males emerge from their cocoons, they immediately fly off and search for another colony. But a male can’t just land and mate with a queen. He has to get through her guards, and they decide whether they like him or not. If they find him adequate, they bite his wings off and bring him to the queen. After he mates, he dies. This sounds like the plot of a weird science fiction novel from the 1960s. If a colony’s queen dies, the worker ants may join another colony.

Let’s talk specifically about the Dorylus genus of army ants for a few minutes, which live in Africa and Asia. Dorylus army ants live in simply enormous colonies. When the colony goes foraging, there may be 15 million ants marching in a dense column, and they can eat half a million animals every single day.

That’s why the army ant is so feared. The column of ants is made up of worker ants in the middle with the much larger soldier ants along the edges. The columns don’t move very quickly, but the ants attack, kill, and eat any living animal they encounter that can’t run away. This includes insects, spiders, scorpions, and lots of worms, but also eggs and baby birds, other baby animals, frogs and toads, and even larger animals. What isn’t eaten on the spot is carried back to the camp to feed larvae and the queen.

Army ants are also beneficial to the ecosystem and to humans specifically in many ways. A column of army ants that marches through a village will eat so many insects that they act like a really high quality exterminating service for homes and gardens. They also scare insects and other animals that flee from the ant columns, and a lot of animals benefit from the general chaos. Birds of many species will follow army ants in flocks, grabbing insects as they flee the ants. Some birds even make special calls to alert others that army ants are on the move, so that everybody gets a chance for easy food. Even more animal species will follow the column to clean up what they leave behind, including partially eaten carcasses, animals that were killed but rejected as food, and even the feces of the birds that follow the ants.

And, of course, a lot of animals just eat the army ants. Chimpanzees make different types of tools to help them safely harvest army ants. Most commonly, a chimp will use a stick it’s modified to the right length and shape, referred to as an ant-dipping probe. It will put one end of the stick down in the column of army ants and wait until ants start climbing up the stick. When there are enough ants on the stick, it will remove the stick and eat the ants off of it. It’s an ant-kebob!

If you’re wondering why the chimps aren’t attacked by the ants, or why the ants don’t figure out they’re climbing a stick to nowhere, Dorylus army ants, like most army ant species, are all blind. They communicate by releasing pheromones, which are chemicals with specific signatures that other ants can sense, something like smells. Some species that mostly live aboveground have re-evolved sight to a limited degree.

The mandibles of Dorylus army ant soldiers are so strong, and the ant is so tenacious about holding on, that people in some East African tribes traditionally use them to stitch up wounds. The soldier ant is held so that it bites with one mandible on each side of a wound, holding the edges of skin together. Then the person severs the ant’s body from its head, killing it—but the jaws are so strong that they will continue to stay in place for several days while the wound heals.

In Central and South America, the army ant genus Eciton [ess-ih-tahn] is very similar to Dorylus. Some species can cross obstacles like streams by building a living bridge out of individuals to allow the rest of the column to cross.

Whew, okay, I should probably have made the army ant its own episode, because there’s so much cool research about it that I could just go on forever. But let’s move on to a much different insect next, a butterfly that lives in the eastern United States, especially in the Appalachian Mountains. This is the Appalachian tiger swallowtail, which has yellow wings with black stripes and a black border, and a black body. Some females have all-black wings with orange spots. When the genetic makeup of the butterfly was examined, it turns out that the species originated as a hybrid of the Eastern tiger swallowtail and the Canadian tiger swallowtail. This kind of hybridization is rare in the wild. The Appalachian tiger swallowtail lives in the mountains, usually in high elevations, and while its range overlaps with both parent species, it almost never hybridizes with either. It has inherited the Canadian butterfly’s tolerance for cold but is twice its size. Researchers estimate that the hybridization occurred around 100,000 years ago.

I learned that interesting fact about the Appalachian tiger swallowtails from the May 2018 Flying Snake issue, and let’s go ahead and learn about a mystery invertebrate I also read about in that issue of Flying Snake.

The mystery is from The Desert Magazine, which was published between 1937 and 1985. It was a monthly magazine that focused on the southwestern United States, with article titles like “Rock Hunter in the Sawange Range” and “Ghost City of the White Hills.” Both those headlines are from the January 1947 issue, which is also where the first mention of the Baby of the Desert shows up in the letters section. Flying Snake excerpts the relevant letters from that issue and a few later issues, but I got curious and found the originals online.

I’ll quote part of the original letter because it’s really weird and interesting:

“Gentlemen: Would like to ask if there is such a thing as a very poisonous desert resident called ‘Baby of the Desert,’ so named because of the resemblance of its face to that of a human baby. Whether this so-called ‘Baby of the Desert’ is supposed to be insect, reptile or rodent, I could not find out. …[I]t was considerably smaller than the Gila monster.”

The letter was signed William M. Weldon from South Pasadena, California.

The editor responded, “The question of the Baby of the Desert, Baby-face, or Niño de la Tierra, as it is variously called, came up for discussion on the Letters page of the magazine two years ago. A reader sent in a description of the fearsome beast as it had been pictured to him and asked for confirmation from someone who had seen it.”

Because of the mention of another letter asking about the Baby of the Desert, two years before, I went through the letters sections of all the 1945 issues to find the original. I couldn’t find it in 1945, but I did find a nice letter from James Mayberry in California, who found a desert tortoise with blue paint on its shell. He thought someone had brought the tortoise back from a visit to the desert. James named the tortoise Mojave but knew it needed to go home, so he sent it to the Desert Magazine. I’m delighted to say that the editor took it out to a lonely desert hill where there were other tortoises and let Mojave go. Tortoises live a long time so Mojave might still be stumping around out there, the blue paint on his shell faded in the sun.

Then I went back through the 1944 issues and found the letter in the July issue. It was from Albert Lloyd of Tulsa, Oklahoma, who wrote, “Perhaps some reader can supply authentic information about a small denizen of the deserts and mesas of the Southwest, which the Mexicans call Niño de la Tierra, or Child of the Earth. During four years of roaming around New Mexico and Arizona I was never fortunate enough to see one. But I have talked with several who claim to have seen it. They describe it as a doll-like animal, about three or four inches in length, walking on all fours, with head and face like that of an infant. They claim it will not attack you unless molested and that its bite is more deadly than a rattlesnake’s.”

The editor of the Desert Magazine suggested that the Baby of the Desert was an insect. “[I]t appears that the Baby-face is actually our old friend the yellow and black striped Jerusalem cricket or Sand-cricket, who is nocturnal and usually found under boards or stones.”

But responses in the letters section in following issues, February and April 1947, don’t agree. S.G. Chamberlin of San Fernando, California wrote, “Some years ago…we uncovered what we first thought to be a Jerusalem Cricket. The coloring was the same and it was a little more than two inches long. Later in the day a ranch hand brought us a Jerusalem Cricket and then we noticed quite a difference in the bodies and heads of the two insects. The round face of the first one did attract our attention although we didn’t think of a baby at the time. The ranch foreman placed them in different bottles to show them to a man in the Farm Bureau office who was versed in such things. He reported back that the first insect was called Vinegarones or Sun Spider and supposed to be harmless.

“At the ranch we were told that on the Mexican border there was a similar insect that is supposed to be poisonous.”

And Coila Harris of South Laguna, California wrote, “I was interested in the recent letters about ‘Baby Face.’ This is not the Jerusalem cricket or potato bug, as many believe, but could be mistaken for one of these insects. Baby-face lives down Mexico way. When we were living in El Paso, one of the weird looking bugs was found under our house. It had a body of a large Tarantula, the head was white as a bleached bone and looked like a bald headed baby, a dreadful thing. I was told at the time that Mexicans consider them so poisonous, that if bitten on the finger by one, they chop off the finger.”

Unfortunately for me, the second I saw the mention of a vinegarone, I had a good idea of what this animal might be. And I really don’t want to look at pictures of vinegaroons.

I do try very hard not to be biased against gross-looking insects, because for one thing, they aren’t hurting me and gross is in the eye of the beholder. One person’s “ooh gross” is the other person’s “Oh, that is so neat!” Spiders don’t bother me and as long as I don’t have to look closely at an invertebrate’s mouthparts and things, I’m usually okay. But I get a big case of the nopes when it comes to the vinegaroon.

The vinegaroon is an arachnid, related to spiders and scorpions. It sort of looks like a mixture of the two, although there are lots of species and they vary quite a lot. It’s also called the whip scorpion. The name vinegaroon comes from the acidic liquid it squirts from the base of its whip-like tail if it feels threatened, which smells like vinegar. It lives in tropical and subtropical parts of the Americas and Asia, with one species known from Africa. Most species prefer dark, humid areas and live in burrows in rotting wood or under rocks and leaf litter, but the giant whip scorpion lives in more arid areas in the southwestern United States and Mexico.

The giant whip scorpion grows to around 2.5 inches long, or 6 cm, not counting the long whip-like tail. Like all vinegaroons, it eats insects, slugs, and other small animals. But no one could look at it and think “baby.” It has big claw-like pedipalps in addition to six walking legs and a pair of front legs that are extremely long and thin, that it uses to feel around with. It has eyes—in fact, like spiders it has eight eyes—but it doesn’t see very well and mostly navigates by touch. It’s dark brown or black with some lighter brown markings on its abdomen.

The Jerusalem cricket looks superficially similar to the vinegaroon although it’s not an arachnid. It’s also not a cricket, and it doesn’t have anything to do with Jerusalem since it’s native to the western United States and Mexico. In fact, it’s related to the weta of New Zealand. It lives in the same sort of places that vinegaroons like, burrowing in moist soil and rotting wood, but it mostly eats decaying plant material although it will sometimes eat small insects. It can bite, although it’s not venomous or poisonous, but it can give off a horrible smell if it’s disturbed. It’s yellowish to dark reddish-brown with a black-striped abdomen and a rounded head. It also does not look anything like a baby.

BUT, while it’s known by a couple of Navajo names that translate to variations on “red skull bug,” in Spanish it’s called cara de niño, which means child’s face, or niño de la tierra.

So I think the Desert Magazine editor was right. The Baby of the Desert is the Jerusalem cricket. But I wouldn’t be a bit surprised if the Jerusalem cricket is sometimes confused with the giant whip scorpion. They’re both large nocturnal creatures with a similar body shape and coloring, that live in the same areas and occupy the same habitat. And they’re both horrifically creepy-looking. You know what? I bet you anything that “Baby of the Desert” and “baby-face” are ironic names. BAD BABY.

The Jerusalem cricket doesn’t have any kind of hearing organs akin to ears but it can sense vibrations. Instead of chirping, it drums its abdomen on the ground to attract a mate. This is what the drumming sounds like.

[Jerusalem cricket drumming]

You can find Strange Animals Podcast online 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 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.

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