♪Intro♪
As kids, lots of us watched cartoons or read books with animals as the main characters.
And even though we knew those stories weren’t real, because animals don’t really speak
English or drop Acme safes on each other, they definitely spread some weird misconceptions
about certain species.
Hopefully a lot of confusion has been cleared up as you’ve gotten older… but we’re
guessing that at least one of these eight debunkings will come as a surprise.
If you grew up with Winnie the Pooh stories, you learned that there’s nothing bears love
more than honey, right?
Well… not exactly.
Bears do raid beehives, but the real prize is the brood, the collective term for the
egg, larva, and pupa stages of developing bees.
Bears find beehives by smell, both wild ones tucked into places like tree cavities and
the boxes maintained by beekeepers.
And they’ll tear hives apart to get at the sweet insides.
The bees, understandably, aren’t thrilled about this.
So they’ll attack a bear’s face and ears, because its thick fur helps deflect their
stings.
Honey is made from the sugary nectar of flowers, so it’s full of carbohydrates like glucose
and fructose.
And, sure, bears will go for honey if it’s there, but it’s not really what their diet
needs.
On the other hand, eating the brood provides a snack full of proteins and fats.
And that helps bears prep for hibernation, when they stop eating or drinking for months
and rely on stored-up nutrients to survive.
And even though beehives may be a nice treat, they only make up a small part of the diets
of both black and grizzly bears.
Bears will also eat roots, berries, other insects, fish, mammals, and pretty much whatever
they can get.
Which, you know, sounds a little more doable than just surviving on sugar.
Cats may seem like they enjoy lapping up a dish full of cow milk, and it’s even a staple
in cartoons like Tom and Jerry.
But surprise: milk is actually pretty bad for their digestion.
Most mammals, cats included, lose their ability to digest milk when they grow up.
It’s like how dairy-loving humans are the weird ones, not the norm.
As kittens, their small intestinal cells naturally make an enzyme called lactase, which breaks
down the sugar found in milk called lactose.
That’s important, because newborn mammals get all their nutrients from milk produced
by a parent’s mammary glands.
So their bodies definitely need to be able to process it.
But, as they grow and start eating other foods, lactase production naturally shuts down.
And when undigested lactose passes through the large intestine, those cells end up secreting
a lot of extra water to deal with it… which leads to diarrhea.
Gut bacteria might also ferment the stuff and produce gas, which causes bloating.
Now, the milk of every mammal species has a unique blend of proteins, fats, and carbohydrates
to meet specific nutrition needs.
So kittens need cat milk to thrive.
Cow’s milk has way more lactose than the average adult cat can handle, and even though
kittens are better at breaking down the sugar, it’s not great for them either.
So leave that kitten with mom until it’s ready to be weaned off of milk.
And then, just stick to kibble or something.
Speaking of drinking stuff, cartoons sometimes show elephants using their trunks like a straw
to suck up water.
Really, though, they can’t do this any more than you can drink through your nose.
Don’t try that, by the way.
And that’s because an elephant’s trunk is the anatomical equivalent of your nose
and upper lip.
After all, most land-dwelling animals are really just the same body plan squashed and
stretched in different ways over millions of years of evolution.
Trunks are basically tubes of muscle tissue, and are used for smelling, picking up food,
communication, and all sorts of other things.
Elephants /do/ use their trunks to drink.
But they do it by sucking water part of the way up, then squirting it into their mouths.
A typical elephant trunk can hold almost 10 liters of water, so it’s a pretty good thirst
quencher!
Or like a huge built-in water gun.
The link between carrots and rabbits has an interesting history.
It all started with Bugs Bunny, but his habit was inspired by the 1934 film It Happened
One Night.
Specifically, Clark Gable’s quick-talking character munches on a whole carrot during
a particularly famous scene involving hitchhiking.
So moviegoers would have recognized the reference in cartoons.
But rabbits don’t eat root vegetables in the wild.
Instead, they mostly go after grasses and weeds, which have lots of long carbohydrates
that are all considered kinds of fiber, which is pretty tough to break down.
Root veggies like carrots have different carbohydrates.
And too much of some kinds of sugars, like small molecules of fructose or certain longer
chains like starch, can lead to tooth and digestive problems.
For instance, there’s a pouch called the cecum between the intestines.
It’s home to lots of microbes that break down molecules like fiber that are hard to
digest.
That broken down stuff gets squeezed into pellets called cecotropes, which rabbits poop
out and eat to have an extra chance to absorb nutrients.
If a rabbit’s diet has too many easily-digestible sugars, like from carrots, the kinds of microbes
that thrive in the cecum can change.
And that throws off whole system.
So protect their poop!
Better food choices for bunnies include hay, grass, and rabbit pellets, while carrots should
only be an occasional treat.
I’m about to ruin all your happy childhood memories of feeding bread crusts to ducks
at the park: bread is actually kind of terrible for birds.
But a lot of people do this.
In 2014, for example, people in England and Wales fed an estimated /six million loaves/
of bread to ducks.
The problem is that bread has very little nutritional value — it’s basically just
starch — but it still fills up the birds and keeps them from seeking out a more nutritious
diet.
Young birds who just eat bread may never learn to forage for themselves.
And a bread-heavy diet, is low in protein and vitamins.
Scientists don’t know exactly why, but these dietary deficiencies can cause a deformity
called angel wing.
The wrist joint in one or both wings starts to twist outward.
If it’s bad enough, angel wing can completely prevent a duck from flying, leaving it vulnerable
to predators.
Not to mention, uneaten bread is bad for the environment, too.
All those extra sugars floating around in ponds and rivers can provide extra food for
microbes, fueling blooms of certain bacteria and algae.
Many of these microbes produce toxins that are dangerous to both people and animals,
so it’s bad news for water quality.
So if you just can’t give up feeding ducks, consider giving them something like oats,
corn, or even lettuce instead of your leftover bread.
Cartoons aside, ostriches don’t really bury their heads in the sand when they’re scared.
But if you’re wondering where the heck this idea came from, zoologists have a few guesses.
Ostriches are the biggest birds in the world, standing two to three meters tall, but they
have really small heads relative to their bodies.
From a distance, if an ostrich is pecking at food on the ground, its head may be hard
to see at all.
So it might seem like it’s tucked underground.
These mega-birds also dig pits in the dirt, about two meters wide and a meter deep, to
use as nests.
They rotate their eggs a few times each day with their beaks, making sure each embryo
is evenly heated and nourished by the goopy nutrients inside.
And this can make it look even more like their heads are vanishing into the ground.
So what do ostriches do when they’re scared?
If they can’t run, and don’t feel threatened enough to fight back, they’ll flop to the
ground with their heads outstretched and hold still, trying to blend in with their surroundings.
Like a stop, drop, and hide kind of situation.
It might seem kind of silly that a huge bird is trying to be sneaky, but it’s way more
effective than just hiding their head and, like, pretending there’s no danger.
Someone has probably warned you that a scared porcupine can launch its quills into the air
to fend off an attacker.
But, as cool as that sounds... it’s not true.
Porcupine quills are basically modified hairs, so they’re sharp, hard, and mostly made
of a structural protein called keratin.
When a porcupine is freaked out, tiny muscles at the base of each quill cause it to stand
upright — like the hairs on your arms when you get goosebumps.
A porcupine’s first line of defense is just to puff up and rattle its quills to try and
scare a threat away.
But a really angry, cornered porcupine may even dash or swing at its attacker to impale
it.
North American porcupine quills have specialized barbs that help them penetrate skin with even
less force than a similar-sized hypodermic needle would need.
Kind of like a serrated knife compared to a flat one.
And once those quills are stuck in something, they detach pretty easily from the porcupine’s
body, but the barbed tips make them really hard to pull out.
Researchers are even looking into these quills to develop better medical technology, like
needles or stitches to stick tissues together.
So surprising a porcupine is still a pretty bad idea, but it can’t actually fire quills
at you like missiles.
The phrase “blind as a bat” gets tossed around quite a bit.
It’s a classic cliche.
But bats actually /aren’t/ blind — they have eyes and can see.
Some bats, especially large species that eat fruit and nectar, can see as well as or maybe
even better than humans.
They rely on their eyes and noses to find food!
Bat species that hunt insects, though, tend to have smaller eyes and rely on an extra
sense called echolocation to forage at night.
They make tiny squeaks or clicks with their mouths or nostrils, usually too high-pitched
for humans to hear.
Then, highly sensitive receptor cells in their ears detect any subtle frequency changes of
returning echos to figure out what’s nearby — like a tasty mosquito.
Bats can definitely see and echolocate well enough to avoid flying into your hair accidentally,
and they have zero interest in getting into it on purpose.
A bat may swoop low over your head if you’re outdoors at night, but it’s just going after
a flying insect that happens to be nearby — not you.
So when it comes to painting an accurate picture of biology, a lot of cartoons, kids’ books,
and common expressions have a lot to answer for.
It turns out Winnie the Pooh and Bugs Bunny are not super accurate examples of their species.
Thanks for watching this episode of SciShow, and if you want to watch more videos starring
all kinds of animals, including a lot of the ones on this list, check our sister channel
Animal Wonders at youtube.com/animalwondersmontana
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