What makes a firefly glow

  • There are over 2,000 individual firefly species, all within the taxonomic family of Lampyridae.
  • But the answer to the lightning bug’s light all happens in the same organ in its abdomen: the lantern.
  • While the firefly may have evolved its lantern as a form of protection, today the lightning bugs use their light as a species-specific mating ritual.
  • Visit Business Insider’s homepage for more stories.

Following is a transcript of the video.

Narrator: There are over 2,000 individual firefly species, all within the taxonomic family of Lampyridae, which is pretty easy to remember. And these lightning bugs with their flickering light shows make summer nights feel all the more magical and romantic. But how did fireflies manage to catch lightning in a bottle? The answer is found in the bug’s butt, or more specifically in its abdomen, in an organ called the lantern. This organ is a set of specialized light cells, all encased in a translucent exoskeleton. And those light cells are where the magic happens: the phenomenon of bioluminescence, when a chemical reaction in a living thing emits light. Fireflies aren’t the only creatures that have this power. Glowworms and certain deep-sea fish species are some of the creatures capable of producing and emitting light. But the firefly is probably the Earth’s most famous bioluminescent species. So what’s happening inside the firefly’s light cells? What’s the secret to its glow?

In the 19th century, French pharmacologist Raphaël Dubois, working with bioluminescent clams, discovered that there are two essential components to these creatures’ light show. He named them luciferin and luciferase, based on the Latin term lucifer, for “light-bringer.” Luciferin is the compound that generates light, and luciferase is the enzyme that acts on it. Today, we know that the firefly’s bioluminescent reaction plays out like this. A firefly diverts oxygen to its light cells through its tracheoles. And those oxygen molecules react to luciferin, catalyzed with the help of luciferase and energy in the form of ATP. The luciferin then becomes agitated and excited, elevating its energy level. And when the excited luciferin drops back to its normal state, it releases that energy in the form of light, creating the “fire” in fireflies. It’s a remarkable phenomenon that’s also remarkably efficient. In a light bulb, 90% of the energy consumed is given off as heat, with only the remaining energy, a mere 10%, given off as visible light. In a firefly, on the other hand, nearly 100% of the energy is given off as light. That luminescence, or “cold light,” as it’s also called, is produced in the light cells and then focused by a layer of reflector cells, which direct that beam outward through that translucent exoskeleton.

But why do fireflies do what they do? As it turns out, bioluminescence has a number of evolutionary benefits, helping certain marine species lure prey to their mouths or serving as a defense against predators.

Sara Lewis: Fireflies are beetles, and so the juvenile fireflies live underground. So, we think that firefly light first evolved as a warning. It’s like a neon sign that shouts out, “Don’t eat me, I’m toxic.”

Narrator: But in adult fireflies, the purpose is a bit more romantic. Those yellow flashes lighting up our warm summer nights are actually part of the fireflies’ complex mating rituals, with male fireflies attracting female fireflies of the same species by flashing a distinctive, recognizable pattern. So those lights twinkling around you, switching on and off seemingly at random – they’re just the opposite: a highly intricate, specialized form of species-specific seduction.

Lewis: In North America, males might flash, like, just one flash. Wait, wait, wait, wait, wait, wait, wait, bleep, another flash, wait, wait, wait, wait, wait, bleep, another flash. Some species, the males actually give paired flashes, so they’ll fly along and then go bleep, bleep, wait, wait, wait, wait, wait, wait, wait. Bleep, bleep, wait, wait, wait, wait, wait. And so on. And so females who are kind of hanging around on grass down below can see these flashes, and they can recognize a male of their own species.

Narrator: But for all the romance and magic they add to our summer evenings, firefly populations around the globe are at serious risk. Those finely tuned mating rituals? Thanks to light pollution, those love letters get a little lost in translation.

Lewis: In areas where there’s a lot of bright lights, it’s been shown that it’s much, much more difficult for the male fireflies to find the females and for the females to see the flashes, the advertisement flashes of the male fireflies.

Narrator: And other threats like habitat loss and pesticide use have also put the population at risk.

Lewis: Sadly, in many parts of the world, there are other firefly species that aren’t doing so well. In fact, they are flickering out. And some of these fireflies are restricted to a very specific habitat. If that habitat goes away, the fireflies disappear. They can’t live anywhere else.

Narrator: It’s a story playing out all over the planet and across the animal kingdom. But as Lewis explains, education is absolutely key to conservation of fireflies and of all at-risk species.

Lewis: If fireflies disappeared, a lot of the world’s wonder would disappear with them. Would you wanna live in a world without fireflies? I would not.

Narrator: By increasing awareness of these risk factors, Lewis hopes to shine a little light on firefly conservation, ensuring that these little bugs will be able to dazzle us for years to come, giving future generations the chance to spend their summer nights trying to catch lightning in a bottle.

EDITOR’S NOTE: This video was originally published in August 2020.

Read the original article on Business Insider

What’s inside the ‘world’s ugliest animal,’ the blobfish

  • The blobfish was crowned the world’s ugliest animal in 2013 – a title it still defends today.
  • But drop this fellow 9,200 feet below sea level, and the water holds up all that flab like a push-up bra, making the fish a little more handsome.
  • Between the skin and the muscles is a lot of fluid. And that’s the secret to the fish’s distinct appearance – and its survival.
  • Visit Business Insider’s homepage for more stories.

Following is a transcript of the video.

Narrator: This creature was crowned the world’s ugliest animal in 2013, a title it still defends today. On land, he’s got a body like Jell-O and a big old frown. But drop this fellow 9,200 feet below sea level, and the water holds up all that flab like a push-up bra, making the fish a little more handsome. Same old fish, but with a little more support. So, what is all that water pressure holding together?

David Stein: Between the skin, that flabby skin, and the muscles is a lot of fluid.

Narrator: This is David Stein, a deep-sea-fish biologist who was lucky enough to dissect 19 blobfishes in the 1970s. Blobfish look blobby because they are full of water. Under their skin, blobfish have a thick layer of gelatinous flesh that floats outside their muscles.

Stein: If you pick up a blobfish by the tail, then it kind of flows to the head.

Narrator: This water-filled, Jell-O-like layer allows the blobfish to stay somewhat buoyant, which is important because blobfishes don’t have a swim bladder.

Stein: And fishes that have swim bladders are able to adjust their buoyancy. They can secrete gas into the swim bladder or remove it. A fish that lives on the bottom doesn’t need to be able to maintain its buoyancy.

Narrator: So, the Jell-O layer isn’t a perfect substitute, but the blobfish doesn’t need to be a strong swimmer. The predator has a highly specialized hunting strategy that’s perfect for the rocky barrens of the deep sea.

Stein: It just sits there and waits for dinner to come by.

Narrator: If all you do is sit, you don’t need much under your skin. Just watery tissue, some yellow pockets of fat, and a smidgen of muscle. In case you hadn’t guessed, blobfishes aren’t exactly yoked. They have very little red muscle, the kind that allows you, a human, to run a mile or a tuna fish to migrate across oceans. Instead, blobfish have a lot of white muscle, which allows them to swim in short bursts and lunge at prey that on occasion ramble by.

This is a baby blobfish. It’s a cleared and stained specimen, meaning all its tissue has been dissolved to show only the bones and cartilage. Those thin red lines you see, they’re the blobfish’s bones dyed red. If you’re having trouble seeing the bones, you’re not the only one. Blobfish have poorly ossified skeletons, meaning they’re thinner and more fragile than the bones of most shallow-water fish. This is another handy deep-sea adaptation, as it takes a lot of precious energy to build strong bones.

But the blobfish saves its energy to develop what might be the most important bone in its body: its jaws, which also happened to be the reason it looks so gloomy. The fish needs enormous jaws so it can snap up any prey that passes by and swallow it whole, maybe even smacking its blubbery lips as it eats. And that brings us to its stomach. If you’re the kind of creature that eats anything that swims by, some surprising things can wind up in your stomach. Stein found a wide range of foods and not-foods in the blobfish he dissected. Fish, sea pens, brittle stars, hermit crabs, an anemone, a plastic bag, and also lots of rocks.

Stein: Their stomach contents kind of bear out the fact that they’re probably not too bright.

Narrator: He also found octopus beaks, the cephalopods’ hard, indigestible jaws. This means that one of the world’s flabbiest fishes has been able to eat one of the sea’s most cunning predators. If you’re surprised, just think about the blobfish’s thick skin. What would it be harder to grab in a fight: a sack of bones or a sack of Jell-O? Stein suspects it might be the latter.

Stein: If the skin is loose, perhaps the suckers can’t really get a good grip on it.

Narrator: Stein found sucker marks across the blobfish’s body, a hint that the fish might’ve been in some deep-sea fights. So while all of this Jell-O might look a little unconventional, well, it seems to have served its purpose. The blobfish is perfectly suited to life in the deep sea, where beauty standards are probably quite different. After all…

Stein: Ugly is kind of in the eye of the beholder.

EDITOR’S NOTE: This video was originally published in December 2020.

Read the original article on Business Insider

What’s inside a wasp’s nest?

    • Wasp’s nests are nurseries.
    • The queen wasp builds the first structure alone, then males add on to it.
    • The nest has special adaptations for maintaining temperature and cells for larvae.
    • See more stories on Insider’s business page.

Following is a transcript of the video.

Michael Mills: This is a wasp nest. In the wild, some of these nests are built underground using clay or mud. But you might be most familiar with the paper nests — the ones built out of saliva and pulp, typically found attached to buildings or trees. And these guys can get big. According to the Guinness Book of World Records, the largest wasp nest was 12 feet long and 18 feet all around. Now, we’re all accustomed to avoiding these nests, because, obviously, wasps are scary, but today we’re going to go inside one, because there are a lot of fascinating factors that make these nests work for wasps and their babies. So, let’s cut into one. Pretty easy to cut through this. The hardest part was definitely here at the top, where you can tell the cells are more dense and wider. If I can give you a scale for how big this is, I mean, like, look at it next to my head. This is like a brick cellphone from the ’90s. The key to this type of nest is the pedicel, or the root. It’s the foundation that the entire nest is built off of. These are the cells. Wasps are like butterflies. They’re what’s called holometabolous insects, meaning they go through a metamorphosis before they become adults, and these cells are basically their cribs.

Petrovicheva: The cells are open when they first are produced. The queen will lay their egg in there, and then it’ll get sealed off.

Mills: They’re shaped similar to a hollow cylinder, or like a regular lead school pencil, and there’s a reason why.

Petrovicheva: The walls of the hexagon hold the other cells. Also, they’re a compact space, so you can get a lot of these cells in very, very small space while still having a very strong structure.

Mills: They’re also perfectly sized to fit both the larva and its roommates.

Petrovicheva: Oftentimes there’s some food laid in with the egg, so when it hatches it has the food in there already. The drones move from cell to cell in a circular motion, making sure that each larva has food. Some wasp species tear up insects for the babies, but other wasps take things further. Mason wasps drop off whole caterpillars for their children to eat alive, while tarantula hawk wasps lay their eggs on tarantulas they sting and paralyze as a birthday feast. Other species lay their eggs inside their prey, and once the larvae hatch, they have a meal waiting for them to chew their way out of.

Petrovicheva: Once the larva is ready to metamorphose, it’ll become a pupa inside the cell still, and then it’ll hatch as an adult.

Mills: Since the cells are both the crib and the cocoon for these wasp babies, the nest must maintain a stable temperature with high humidity. This means as much insulation as possible. For these types of nests, the domes are almost always made of salivary secretions, plant material, or paper or cardboard.

Petrovicheva: So, they take wood, they chew it up, and they mix it with saliva to make a glue, and then they lay it in thin layers. The denser the layers, the stronger and more sturdy the structure. After building the core structure, the queen wraps the entire nest in an envelope — these thin sheets of macerated pulp.

Mills: This layer basically protects the comb, or each layer of cells, limiting the entrance to one tiny little hole. Scientists think this helps to maintain the internal temperature and humidity of the structure. And more cones can be added on with more pedicels, sort of like expanding a mansion with tiny little staircases that the wasps can use to get from one area to another. So, now I know the question on some of your minds is, “Is there honey in a wasp nest?” And the answer is no. While both bees and wasps pollinate flowers, bees actually farm nectar to turn it into honey, the food source for their larvae. Most wasps, on the other hand, are meat eaters and prefer a diet of freshly chewed insects, meaning you won’t find honey in their nests, but you might find a lot of dead bugs. So, the next time you see one of these nests and you’re tempted to knock it down, maybe back off. Those wasps put a lot of effort into building this crib for their babies. We don’t want to tick them off.

Read the original article on Business Insider

What’s inside an elephant trunk

  • Elephant trunks are some of the most impressive noses in the animal kingdom.
  • Trunks are organs called muscular hydrostats and they contain around 40,000 muscles that contract and expand to create intricate movements.  
  • Elephants have a stronger sense of smell than any other animal scientists have studied, and can even sniff out landmines in Africa.
  • Visit the Business section of Insider for more stories.

Following is a transcript of the video.

Narrator: What if you could use your nose to snorkel, or uproot a small tree, or smell water from several miles away? Well, elephants wouldn’t be that impressed. They do it on the daily, thanks to what’s inside their trunk.

If you were to dissect an elephant trunk, it would actually look more like the inside of your tongue than your nose. Trunks, tongues, and even octopus arms are unique organs called muscular hydrostats. That means they’re made almost entirely of muscle, and an elephant’s trunk has a lot of them, about 40,000, compared to around 650 muscles in the entire human body. Normally, muscles depend on bones and joints to move and exert force.

When we pick up a dumbbell, for example, our bicep pulls on our forearm bones and that causes them to swing up around our elbow joint. But in an elephant trunk, there are no bones to pull and no joints to hinge on. The muscles take on that role instead. This makes trunks incredibly flexible so they can move in all directions. And all those muscles mean they’re powerful enough to lift hundreds of pounds, yet delicate enough to pick up a tortilla chip without even cracking it.

But while trunks may be structured like a tongue and function like an arm, they are, in fact, a nose, and an exceptional one. An animal’s sense of smell is linked to the number of olfactory receptor genes it has. And elephants, well, they have a lot of them, nearly 2,000 – more than any other animal we know of. Bloodhounds, for example, only have about 800 while humans have even fewer. In fact, an elephant’s nose is so good it can actually sniff out bombs. People have reported that African elephants avoid land mines in Angola and in 2015, researchers put it to the test. Elephants were presented with a lineup of buckets filled with different smells, including TNT, the main ingredient in land mines. Out of 97 TNT samples, elephants detected all but one.

Of course, their trunks didn’t evolve as bomb detectors. They use their nose like we use our eyes, to find food and water, to avoid predators, and to map out other elephants nearby. That’s like walking into a family reunion with your eyes closed and knowing exactly where everyone is. But if you can believe it, there are even more tricks up their, trunks. When elephants traverse deep rivers, for example, they curve their trunk into a snorkel, and when bathing, they can use it as a hose, or more like a fire hose. With one suck, a trunk can pull in as much as 10 liters of water.

And the trunk’s impressive abilities haven’t gone unnoticed. In fact, if you stick a mirror in front of an elephant, one of their favorite activities is to open their mouth and check out their trunks. Let’s admit it, if you had a nose like that, you would do the exact same thing.

EDITOR’S NOTE: This video was originally published in January 2019.

Read the original article on Business Insider

What’s inside a blobfish, the ‘world’s ugliest animal’

  • The blobfish was crowned the world’s ugliest animal in 2013 — a title it still defends today.
  • But drop this fellow 9,200 feet below sea level, and the water holds up all that flab like a push-up bra, making the fish a little more handsome.
  • Between the skin and the muscles is a lot of fluid. And that’s the secret to the fish’s distinct appearance — and its survival.
  • Visit Business Insider’s homepage for more stories.

Following is a transcript of the video.

Narrator: This creature was crowned the world’s ugliest animal in 2013, a title it still defends today. On land, he’s got a body like Jell-O and a big old frown. But drop this fellow 9,200 feet below sea level, and the water holds up all that flab like a push-up bra, making the fish a little more handsome. Same old fish, but with a little more support. So, what is all that water pressure holding together?

David Stein: Between the skin, that flabby skin, and the muscles is a lot of fluid.

Narrator: This is David Stein, a deep-sea-fish biologist who was lucky enough to dissect 19 blobfishes in the 1970s. Blobfish look blobby because they are full of water. Under their skin, blobfish have a thick layer of gelatinous flesh that floats outside their muscles.

Stein: If you pick up a blobfish by the tail, then it kind of flows to the head.

Narrator: This water-filled, Jell-O-like layer allows the blobfish to stay somewhat buoyant, which is important because blobfishes don’t have a swim bladder.

Stein: And fishes that have swim bladders are able to adjust their buoyancy. They can secrete gas into the swim bladder or remove it. A fish that lives on the bottom doesn’t need to be able to maintain its buoyancy.

Narrator: So, the Jell-O layer isn’t a perfect substitute, but the blobfish doesn’t need to be a strong swimmer. The predator has a highly specialized hunting strategy that’s perfect for the rocky barrens of the deep sea.

Stein: It just sits there and waits for dinner to come by.

Narrator: If all you do is sit, you don’t need much under your skin. Just watery tissue, some yellow pockets of fat, and a smidgen of muscle. In case you hadn’t guessed, blobfishes aren’t exactly yoked. They have very little red muscle, the kind that allows you, a human, to run a mile or a tuna fish to migrate across oceans. Instead, blobfish have a lot of white muscle, which allows them to swim in short bursts and lunge at prey that on occasion ramble by.

This is a baby blobfish. It’s a cleared and stained specimen, meaning all its tissue has been dissolved to show only the bones and cartilage. Those thin red lines you see, they’re the blobfish’s bones dyed red. If you’re having trouble seeing the bones, you’re not the only one. Blobfish have poorly ossified skeletons, meaning they’re thinner and more fragile than the bones of most shallow-water fish. This is another handy deep-sea adaptation, as it takes a lot of precious energy to build strong bones.

But the blobfish saves its energy to develop what might be the most important bone in its body: its jaws, which also happened to be the reason it looks so gloomy. The fish needs enormous jaws so it can snap up any prey that passes by and swallow it whole, maybe even smacking its blubbery lips as it eats. And that brings us to its stomach. If you’re the kind of creature that eats anything that swims by, some surprising things can wind up in your stomach. Stein found a wide range of foods and not-foods in the blobfish he dissected. Fish, sea pens, brittle stars, hermit crabs, an anemone, a plastic bag, and also lots of rocks.

Stein: Their stomach contents kind of bear out the fact that they’re probably not too bright.

Narrator: He also found octopus beaks, the cephalopods’ hard, indigestible jaws. This means that one of the world’s flabbiest fishes has been able to eat one of the sea’s most cunning predators. If you’re surprised, just think about the blobfish’s thick skin. What would it be harder to grab in a fight: a sack of bones or a sack of Jell-O? Stein suspects it might be the latter.

Stein: If the skin is loose, perhaps the suckers can’t really get a good grip on it.

Narrator: Stein found sucker marks across the blobfish’s body, a hint that the fish might’ve been in some deep-sea fights. So while all of this Jell-O might look a little unconventional, well, it seems to have served its purpose. The blobfish is perfectly suited to life in the deep sea, where beauty standards are probably quite different. After all…

Stein: Ugly is kind of in the eye of the beholder.

Read the original article on Business Insider