Hi Squeaks!
Do you have your snacks ready for our picnic by the pond?
Oh, I see.
Squeaks is feeling anxious.
Our friend Juniper.
The Worm warned him that eating food outside might attract some hungry bugs and he's worried they're going to eat his food.
It's okay, Squeaks.
We have plenty of snacks to share.
And besides, not all insects like to eat food like this.
In fact, some insects can't eat food like this.
Well, insect mouths are very different than my mouth or yours.
For instance, while we have things like lips, teeth and tongues, an insect has a whole bunch of different parts to their mouth.
And depending on the species or type of insect, those parts can come in different shapes and sizes.
So two kinds of insect may have very different-looking mouths.
Can you think of why that might be?
That's okay.
There are lots of possible answers.
Maybe think about what you and I use our mouths for that an insect would, too.
Ooh, that's right!
Yes, we can all use our mouths to eat.
And not all insects eat the same things.
Some insects, at least during certain parts of their lives, only drink liquid like the sugary sweet nectar found in flowers.
Let's imagine we're one of those insects and this glass of water is a flower with some nectar inside.
If we're an insect, we can't lift the glass up to our mouths and pour the water in.
So how could we drink it?
Yes, we could use a straw!
And that's exactly why some insects have a long proboscis.
It acts like a built-in straw for them to drink the nectar that they need.
A proboscis is made from two mouthparts called maxillae.
They join together to form a long, skinny tube that's held together by hooks.
Imagine if you could stick your lips out in an O shape and make a really long straw!
A face straw!
I love it!
And these face straws can be really long.
The longest proboscis belongs to a moth called Wallace's sphinx moth, and it's up to 30 centimeters, or almost 12 inches long.
That's, like, this long!
It's longer than the rest of the moth's body.
Can you imagine having a mouth longer than the rest of you?
This species of moth uses their super-long proboscis to drink the nectar at the bottom of a similarly long flower called a Madagascar star orchid.
In fact, they're the only insect that has a long enough proboscis to slurp that yummy nectar up!
But not every insect with a proboscis drinks nectar.
There's another insect you've probably seen before that uses a proboscis to do something way different.
They use their proboscis to drink blood.
Yes, mosquitoes have a proboscis, too!
And after they use them to feed on us, they give us those itchy, red bumps we call mosquito bites.
But that mosquito didn't really bite us.
Instead, the proboscis pokes a hole in our skin.
So it's a little bit more like getting a shot at the doctor's office.
Oh yes, piercing a juice box with a straw, which I agree is a lot more fun to do.
You're right, Squeaks!
Insects can eat more than liquids like nectar and blood.
They can eat leaves, pollen, fruit, and even other insects.
And a face straw wouldn't help you eat all of those.
So insects that need to chew have a different shaped mouth.
They use mouthparts called mandibles to crush up their food.
That's right!
We've talked about mandibles before.
Lots of other animals, including humans, have a mandible.
Here's a little refresher.
Mandible is the scientific name for the bone of our lower jaw.
But while my mandible mostly moves up and down, when I chew, an insect's pair of mandibles crunches in from side to side.
And because some foods are much softer than other foods, different insects need to bite harder to chew their dinners.
Like how you have to crunch down on a carrot, but not on a banana.
That's a great question, Squeaks!
He wants to know what the strongest insect bite is.
The strongest biter out of all the insects is called a raspy cricket.
They mostly eat grasses, seeds, and sometimes other insects.
You're right, Squeaks.
None of that food is that tough to bite through.
But raspy crickets don't just use their mouths for eating.
They also use them for digging!
See, raspy crickets use their mandibles to burrow into tree trunks.
So they have to have really strong mouths to dig through that wood.
But even though they have the strongest mandibles, there's another insect that has way bigger mandibles.
Do you want to see it?
Alright, this is called a stag beetle.
Stag beetles get their name because people thought their giant mandibles looked like the antlers on a stag, which is a name for a male deer.
And those massive mandibles sure look impressive!
But stag beetles spend most of their lives looking very different.
After hatching from an egg, they spend several years living underground as a grub or larva.
No fake antlers in sight!
Now, Squeaks, based on what we've learned about mouths, what do you think this stag beetle uses its mandibles for?
Oh, using it to eat something really big?
That's a great guess!
But this beetle actually doesn't use their mandibles for eating at all.
They eat most of the food they need for their whole lives when they're a larva.
Adults will drink nectar, but they use their antler-like mandibles for something else.
Can you think of what that might be?
Maybe something that deer use their real antlers for?
Ooh, that's a great guess!
Yes, they use them to fight.
Male stag beetles will grab each other with their mandibles and fight over who gets to breed with female stag beetles.
And the males that have the bigger mandibles are more likely to win those fights and have more babies.
Yeah, they're just another amazing thing that we get to learn about in our world.
But you know what?
All this talk has got my tummy rumbling.
I'm ready to head outside and enjoy our picnic.
And maybe while we're outside, we can look for some insects to learn more about later.
How's that sound?
Ooh, a ladybug!
How cool!
Ladybugs are insects that have a very important job in the fort's greenhouse.
They eat a lot of garden pests, and they help to keep our flowers and vegetables healthy.
Oh, Squeak says ladybugs are his favorite kind of bug.
But did you know that ladybugs aren't actually bugs?
It's true!
Do you remember what we learned about insects' body squeaks?
Right!
Insects have three main body segments, a head, a thorax, and an abdomen.
And sticking out of that thorax, they have six legs.
There are some other living things that you or I might call bugs, like spiders or roly-polies, that aren't insects because they don't have the right body parts.
But here's the thing.
They aren't bugs, either.
I know, right?
But scientists use the term bug to refer to a very specific group of insects called the true bugs.
In other words, all bugs are insects, but not all insects are true bugs.
You would think a ladybug would be a bug, wouldn't you?
But this is where it can get tricky.
Some insects have the word bug as part of their name, but they aren't true bugs.
Ladybugs are actually a kind of beetle, and beetles are not true bugs.
How do we know?
Well, just like all insects share a few important body parts.
There are some things that true bugs have in common.
For one thing, they have very special mouthparts.
Here's a picture of the mouthparts of a true bug.
What do you notice about their shape or structure?
Yeah!
Their mouthparts look really sharp.
True bugs use them to jab into plants or other animals to suck out the juices inside.
Yeah, I know, it sounds a little yucky, but even bugs have to eat.
True bugs also grow and develop differently than many other insects.
Insects like ladybugs and butterflies Begin life in an egg that hatches into a larva.
That larva then changes into a pupa, and when the pupa breaks open, an adult insect enters the world.
But true bugs don't go through all of those steps.
Instead, a bug hatches from its egg into something called a nymph.
And unlike larvae, which look a lot more like blobs or worms, nymphs look a lot more like an adult bug.
And over time nymphs get bigger and grow some additional body parts, like wings, until they reach adulthood.
Right!
Ladybugs don't have mouthparts that are shaped in a way that lets them jab and suck.
And they go through both a larva and a pupa stage of life, so they are not true bugs.
But the aphids they eat are bugs!
They have sharp mouthparts to suck out the yummy sugary liquid inside of plants.
Right, that's not very good for the plant.
Plus, aphids can carry diseases.
That's why ladybugs are so good to have around the garden.
They eat aphids and help keep the plants safe.
But aphids are still pretty cool because, depending on where they live, they have babies in different ways.
In places with a cold winter, they'll lay eggs that wait until spring to hatch.
But in places where it's warm all year, female aphids don't lay eggs at all.
They give birth to live babies.
Yeah, it's pretty unusual for a bug.
All living things reproduce, or make babies, but they certainly don't all reproduce in the same way.
The same is true for the way things develop and grow.
For example, another group of true bugs are called assassin bugs.
Yeah, this time bug is in the name, and the insect really is a bug.
And like all true bugs, assassin bugs lay eggs that hatch into nymphs.
But their nymphs act very differently than the adults.
Some of them stick pieces of dead insects to their backs.
What?
You don't think that's cool?
It's a trick the nymph uses to hide from predators so it doesn't get eaten.
Nature can seem pretty strange sometimes, but even behavior that's strange to a human or a robot rat can help a living thing survive.
And it's not the only disguise an assassin bug can wear.
For example, a different species or type of assassin bug has a body part that is shaped kind of like a wheel sticking out of their back.
This part develops as the insect grows and gives the insect their nickname, a wheelbug.
Oh yes, the assassin bugs get their name because they use their sharp mouthparts to eat other insects.
After piercing their prey, they can squirt digestive juices into the other insect's body and then slurp the insides out.
However, there is one group of assassin bugs that just sucks blood, including human blood.
Well, kind of like mosquitoes.
Mosquitoes do have mouthparts that can pierce our skin, but they're not the same kind that bugs have.
Mosquitoes are actually a type of fly, and just like beetles, flies aren't true bugs.
These blood-drinking assassin bugs are sometimes nicknamed kissing bugs because they bite around an animal's mouth, but it's not a very nice kiss.
And they can also spread disease.
Some kissing bugs carry teeny, tiny critters called parasites that can travel to the animal they're feeding on and then make that animal sick.
And that includes humans, so it's best to admire any cool-looking assassin bugs from a distance.
Oh, Squeaks wants to know if bugs do anything helpful.
Yeah, so far we've learned about bugs that can hurt our plants and make us sick, but that doesn't mean bugs are bad.
They have a role to play in nature just like every other living thing.
There's also one kind of true bug, called a cochineal bug, that humans grow on special farms for a very important purpose.
These small bugs suck the juices out of cacti and are especially fond of prickly pears.
They also make a special chemical in their bodies that makes them taste really bad, so ants won't eat them.
Yes, instead of piling a bunch of dead insect bodies on their back, yes.
But a long time ago humans figured out that if you can collect this chemical and mix it with some other ingredients, we can make a really pretty red dye called carmine.
In fact, people have been making this bug-based dye and using it to color things like clothing for thousands of years.
So we have insects in our greenhouse to help plants grow, but other people have greenhouses full of cacti because they want to help their bugs grow.
Yeah, and you know what else is pretty neat?
Cochineal bug nymphs make a sort of wax coating to help protect themselves from the sun, sort of like a self-made sunscreen.
And if the cactus plants they're living on get a bit too crowded, they can also make a waxy string that will carry them away to a plant that's got a bit more elbow room.
I don't know if we should get them for our greenhouse.
Maybe we should ask Juniper what she thinks before we add any prickly pears and cochineal bugs to the greenhouse.
Should we go find her now?
Wow, Squeaks, our friends took so many photos from their vacations last year.
Hey, you want to play a game?
I'll show you a photo, and you tell me what you can see in it.
Okay, here's the first one.
Are you sure it's just a plant?
I think you should look again.
That's right!
There's a caterpillar hiding in plain sight!
Actually, I think this is a hornworm.
Hornworms are caterpillars that use their green color and smooth body shapes to blend into the plants they like to eat, including tomato plants.
So sneaky.
Okay, how about this one?
Oh, you think it's bird poop?
Nope.
It's another caterpillar.
This species or type of caterpillar spends a lot of its time on the tops of leaves which, I do admit, can have bird poop on them too.
Okay, last one.
You're catching on, Squeaks.
This may look just like a stick, but it's actually a caterpillar, too!
And unless you sat and watched them for a really long time, you wouldn't realize that they're not part of the plant they're munching on.
But most predators don't have the time to do that.
I guess I was playing a little trick on you.
I showed you photos of caterpillars that looked like something else.
They were camouflaged.
Camouflage is a way to hide in plain sight by blending into your surroundings.
You or I can put on clothes to camouflage ourselves, like wearing a shirt covered in a green leaf pattern to hide in a forest.
But many animals have camouflage built into their bodies, including many caterpillars.
Can you think of why a caterpillar might want to camouflage themselves?
Good idea, Squeaks!
Caterpillars are basically a protein-packed gummy worm.
They crawl around the garden eating all day long, building up the energy and supplies they'll need inside their body to transform into a butterfly or a moth.
But those little caterpillars can't move very quickly.
And what predator wouldn't want to snack on a slow, savory gummy worm?
So in order to make it to that butterfly phase of their lives, caterpillars have to come up with creative tricks to avoid being eaten, so they can grow up into beautiful butterflies and make some more caterpillars.
And one of the tricks is camouflage.
A predator probably wouldn't have the patience to sit and stare at a plant to see if one of its sticks is really a piece of food.
And just like you thought the caterpillar that looked like bird poop was gross, so would the animals that want to eat a delicious caterpillar.
Oh.
Camouflage isn't a trick the caterpillars were taught.
The instructions for how to look like bird poop or a stick are inside a caterpillar's body.
Scientists call that special look a trait, and the caterpillar inherited or was passed down the instructions for that trait from their parents, who also looked like bird poop or a stick.
Can you think of a trait that I inherited from my parents?
That's right, I do have the same nose as my dad!
But the instructions to make human facial features are actually kind of complicated, so not every kid out there will have the same face as their parents.
Also, having my dad's nose doesn't help me avoid getting eaten by predators.
At least, I'm pretty sure it doesn't.
Great question.
I did say camouflage was just one trick a caterpillar might use.
So, some caterpillars inherit different looks to keep themselves safe.
For example, some are disguised to look like something that's way more dangerous than they really are.
Check this one out.
This is a hawk moth caterpillar.
What do you notice about their markings and the shape or structure of their body?
What do they remind you of?
Yes, their body looks like the head of a venomous snake which most predators know they should steer clear of.
Yeah, the caterpillar inherited the traits to look like a snake, and their predators inherited the knowledge that snakes are dangerous.
This is a hickory-horned devil caterpillar, which gets their name from the spikes all over their body.
They sure look like they would be painful to eat, right?
But they're actually really just a giant squishy thing.
Those spikes are a trick, but most predators wouldn't risk touching them anyway.
Here's a caterpillar of a swallowtail butterfly.
They have a brightly colored forked body part on their head that they flash when they feel threatened.
But it's not just for show.
This body part also releases a bad smell, which predators might think is poison.
Here's a Saddleback Caterpillar, which combines a bunch of different tricks to survive.
They're colorful and have a few large spiky-looking bits.
But do you see those tiny hairs?
The hairs have even tinier hooks that can dig into your skin and once they're in, they can deliver a toxin.
Yeah, that one is definitely a caterpillar you don't want to touch, as they can really hurt you.
And there are other caterpillars who take that toxic hair trick to a whole new level.
This one is sometimes called the toxic toupee because it looks like someone's wig crawling around.
I guess they do look kind of cute, but you definitely don't want to touch them.
The hairs cause stings that are incredibly painful, probably one of the worst stings you've ever felt.
So the next time you see a caterpillar, see if you can spot what tricks and traits they may be using to avoid being eaten.
