Animal Behavior - CrashCourse Biology #25 - Lake Harding Association

Animal Behavior – CrashCourse Biology #25

Animal Behavior – CrashCourse Biology #25

By Micah Moen 100 Comments August 14, 2019


Behavior is action in
response to a stimulus. My cat Cameo is now responding
to both an external stimulus the sound of a bag of treats,
and an internal stimulus her hunger, or at least her
insatiable desire for treats. Sometimes animal behavior
can seem really far out, but if you look closely enough, you can see how all
behavior serves a purpose to help an animal mate, eat,
avoid predators, and raise young. And since behaviors can come
with advantages like these, natural selection acts on them
just as it acts on physical traits ensuring the success
of animals who engage in beneficial behaviors, while
weeding out those that do stupid, dangerous or otherwise
unhelpful stuff. The most beneficial behaviors
are those that make an animal better at doing the only two
things in the world that matter: eating and sex. Still, that doesn’t mean
all behavior is about just looking out for number one. It turns out some
advantageous behavior is actually pretty selfless. More on that in a minute. But first, behavior is really just
a product of a pair of factors: Morphology, or the physical
structure of an animal and physiology, or the
function of that morphology. Now, an animal’s behavior
is obviously limited by what its body
is capable of doing for example, Cameo does
not have opposable thumbs, so, much as she would like
to get into the treat bag, by herself, she cannot. This limitation is
strictly hereditary no cats can open treat
bags with their thumbs because no cats
have opposable thumbs. Though some cats do have thumbs. In the same way that a penguin
can’t fly to escape a predator; or a gazelle can’t reach the
same leaves as a giraffe can. Similarly, behavior is constrained
by an animal’s physiology. Like, Cameo’s built for
chasing down little critters and eating meat,
not beds of lettuce. This is because her physiology,
everything from her teeth to her digestive system,
are geared for eating meat. If she pounced on and ate every
blade of grass she came across… let’s just say I would not want
to be in charge of that litter box. Now the traits that make
up an animal’s morphology and physiology are
often heritable, so we generally talk about
selection acting on those traits. But as natural selection
hones these traits, it’s really selecting
their associated behaviors. It’s the USE of the trait, using wings and feathers
to escape predators, or using a long neck
to reach leaves, that provides the
evolutionary advantage. Still, that doesn’t mean
all behavior is coded in an animal’s genes some behaviors are learned. And even for animals that
learn how to do things, natural selection has
favored brain structures that are capable of learning. So one way or another, most behaviors have
some genetic underpinning, and we call those
behaviors adaptive. Problem is, it’s
not always obvious what the evolutionary advantages
are for some of the nutty things that animals do. Like, why does a snapping turtle
always stick out its tongue? How does a tiny Siberian
hamster find its mate, miles across the
unforgiving tundra? Why does a bower bird
collect piles of garbage? To answer questions like those, we have to figure out what
stimulus causes these behaviors, and what functions
the behaviors serve. To do this, I’m going to need
the help of one of the first animal behavior scientists ever,
or ethologists, Niko Tinbergen. Tinbergen developed a
set of four questions aimed at understanding
animal behavior. The questions focus on
how a behavior occurs, and why natural selection has
favored this particular behavior. Determining how a behavior occurs
actually involves two questions: One: what stimulus causes it? And two: what does
the animal’s body do in response to that stimulus? These are the causes
that are closest to the specific behavior
we’re looking at, so they’re called
the proximate causes. In the case of the
male Siberian hamster, the stimulus is a delicious
smelling pheromone that the sexy female hamster
releases when she’s ready to mate. The male hamster’s response,
of course, is to scuttle, surprisingly quickly, over
several miles if necessary to find and mate with her. So the proximate cause
of this behavior was that the girl hamster signaled
that she was ready to knock boots, and the male ran like crazy
to get to the boot-knockin’. Asking the more complex question
of why natural selection has favored this behavior requires
asking two more questions: One: what about this behavior
helps this animal survive and/or reproduce? And two: what is the evolutionary
history of this behavior? These, as you can tell,
are bigger-picture questions, and they show us the ultimate
causes of the behavior. The answer to the first
question, of course, is that the ability of a male
hamster to detect and respond to the pheromones of an ovulating
female is directly linked to his reproductive success! As for the second question, you
can also see that male hamsters with superior pheromone detectors
will be able to find females more successfully than
other male hamsters, and thereby produce more offspring. So natural selection has honed
this particular physical ability and behavior over
generations of hamsters. So, who would have thought to ask
these questions in the first place? And where’s my chair? Niko Tinbergen was
one third of a trifecta of revolutionary ethologists
in the 20th century. Along with Austrians Karl
von Frisch and Konrad Lorenz, he provided a foundation
for studying animal behavior and applied these ideas to
the study of specific behaviors and for that all three shared
the Nobel Prize in 1973. You may have seen the famous
photos of young graylag geese following obediently
in a line behind a man. That was Lorenz,
and his experiments first conducted in the 1930s
introduced the world to imprinting, the formation of social
bonds in infant animals, and the behavior that includes both
learned and innate components. When he observed newly
hatched ducklings and geese, he discovered that
waterfowl in particular had no innate recognition
of their mothers. In the case of graylag geese,
he found the imprinting stimulus to be any nearby object
moving away from the young! So when incubator-hatched
goslings spent their first hours with Lorenz, not only did they follow him, but they showed no recognition
of their real mother or other adults in their species! Unfortunately, Lorenz was
also a member of the Nazi party from 1938 to 1943. And in response to
some of his studies on degenerative features
that arose in hybrid geese, Lorenz warned that it
took only a small amount of “tainted blood” to have an
influence on a “pure-blooded” race. Unsurprisingly, Nazi party
leaders were quick to draw some insane conclusions from
Lorenz’s behavioral studies in the cause of what
they called race hygiene. Lorenz never denied
his Nazi affiliation but spent years trying to
distance himself from the party and apologizing for getting
caught up in that evil. Now how exactly does
natural selection act on behavior out
there in the world? That’s where we turn to
those two types of behavior that are the only things
in the world that matter: eating and sex-having. Behavior associated with
finding and eating food is known as foraging,
which you’ve heard of, and natural selection can act
on behaviors that allow animals to exploit food sources while using the least
amount of energy possible this sweet spot is known as
the optimal foraging model. And the alligator snapping
turtle has optimal foraging all figured out. Rather than running around
hunting down its prey, it simply sits in the water,
and food comes to him. See, the alligator snapping
turtle has a long, pink tongue divided into two segments,
making it look like a tasty worm to a passing fish. In response to the stimulus
of a passing fish, it sticks out its tongue
out and wiggles it. Natural selection has,
over many generations, acted not only on turtles with
pinker and more wiggly tongues to catch more fish, it’s also
acted on those that best know how and when to wiggle those
tongues to get the most food. So it’s selecting
both the physical trait and the behavior that
best exploits it. And what could be sexier than
a turtle’s wiggly tongue dance? Well, how about sex? As we saw with our friend
the horny Siberian hamster, some behaviors and their
associated physical features are adapted to allow an
animal to reproduce more, simply by being better
at finding mates. But many times, animals of the
same species live close together or in groups, and determining
who in what group gets to mate creates some interesting
behaviors and features. This is what sexual
selection, is all about. Often, males of a species will
find and defend a desirable habitat to raise young in, and
females will choose a male based on their territory. But what about those species,
and there are many of them, where the female picks a
male not because of that, but because of how he
dances, or even weirder, how much junk he’s collected? Take the male bower bird. He builds an elaborate hut,
or bower, out of twigs and bits of grass, then spends
an enormous amount of time collecting stuff, sometimes
piles of berries, and sometimes piles of
pretty, blue, plastic crap. Ethologists believe that
he’s collecting the stuff to attract the female to check
out his elaborate house. Once the female’s been
enticed to take a closer look, the male starts to sing
songs and dance around, often mimicking other species,
inside of his little house for her. Females will inspect
a number of these bowers before choosing who to mate with. Now, doing more complex dances
and having more blue objects in your bower scores
bigger with females. And ethologists have shown that
a higher level of problem solving, or intelligence,
in males correlates to both of these activities. So yeah, it took some
brawn to build that bower and collect all that junk,
but chicks also dig nerds who can learn dances! So the bowerbird’s brain
is evolving in response to sexual selection by females. This intelligence
likely also translates into other helpful behaviors
like avoiding predators. So thanks to the
evolution of behavior, we’re really good at taking care of
our nutritional and sexual needs. But what’s confused
scientists for a long time is why animals often
look after others’ needs. For instance, vampire bats
in South America will literally regurgitate blood into the
mouths of members of its clan who didn’t get a meal that night. How do you explain animals who
act altruistically like that? We actually did a whole SciShow
episode on this very subject but basically, we can thank British
scientist William Hamilton for coming up with an equation to
explain how natural selection can simultaneously make
animals fit and allow for the evolution of altruism. Hamilton found that the
evolution of altruism was best understood at the
level of larger communities, especially extended
animal families. Basically, altruism can evolve
if the benefit of a behavior is greater than its
cost on an individual, because it helped the
individual’s relatives enough to make it worth it. Hamilton called this
inclusive fitness, expanding Darwin’s
definition of fitness basically, how many
babies somebody’s making to include the
offspring of relatives. So I guess the only
question left is, if I forget to feed you two, who is going to regurgitate blood
into the other one’s mouth? Yeah, there’s probably a reason
that only happens with bats. Thank you for watching this episode
of Crash Course Biology. Thank you to Cameo for
being such a good kitty. Yeah, she finally gets her treats. There’s a table of
contents, of course. If you want to reinforce any of the
knowledge that you gained today. If you have questions or ideas
for us you can get in touch with us on Facebook or Twitter, or
of course, in the comments below. We’ll see you next time.

100 Comments found

User

aaron silvera

You have a cat?

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Rachael Marie Newport

aww Hank your kitty is GORGEOUS how well does she get along with the dogs?

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Roel Vink

The fact that the whole human race is behaving as animals (chasing pleasure, fighting, sexuality) ~is at cost of our own minds~ Your mind produces and sends you things that do not come from life; it sends you things it makes up itself. It creates and sends you emotions, desires, thoughts, guilt, fears and worries, etc It wants to be in control of your behaviour, letting you live like a animal, instead of letting you live as your trueself your spiritual self {Wanna know more} Google TruthContest and read the Present

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Sarah Mumbert

bowerbirds are the cutest things ever :')

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rina hu

You speak so fast :/

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Amz 183

Thank you!

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pangaeus

rB>C !!!!

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luminousstrawberries

Super interesting! I also laughed loudly like 6 times – oh those sexy hamsters ^.^

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Paula Hervert

hey! i love your videos and i would like to ask you to make one about animal traffic. thank you 🙂

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Danimessi 1234

What's the dogs name at the back

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Antaia Christou

the reference page does not work for me. does it work for everyone else?

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Sigal Stein

Altruism IS evolution. Humans rear their young for 18 to 25 years. We should really not feel committed to the GrimaWormtonguing of crooks. They were born to selfish parents and had traumatic childhoods – not too evolved. If evolution was about hostile behaviors then the Nazis would have won WWII for being the ones more fit. The opposite happened – they deteriorated the entire country. In the same way, attorneys and judges are nothing more than predatory parasites. Atrocities are free. Why are we financing a huge Justice Department that gobbles up billions hourly to produce the same atrocities and injustices? They may think that they are more fit because they have duped societies into housing crashes, poverty, hunger, war and disease. But each time communication tools progress these predators have to up their game to keep up the exploitation. Humans have won over these predators in WWI & WWII. I think it is in one of your World History classes – evolution is from predatory warring societies to more peacefully sharing trading societies. The new world order bars attorneys from both the legislative & judicial branch – allowing people freedom from gibber-jabber. It could become possible to regulate bankers & doctors and prevent both Capitol-generated housing busts and diseases.

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Melinda Meyer

It's a Cameo cameo! 😀

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Skippy the Magnificent

Hank, please tell me you don't lock your dog in that cage at night (or ever). If it's just like an indoor dog house or bed where she can come and go as she pleases, that's cool, but dogs shouldn't be forced to stay in cages.

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Marisabel

Lemon, we miss you! <3

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Michela Gray

HELL YES I DIG NERDS WHO CAN LEARN DANCES

Love Crash Course!

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niccyknickers

you said penguin but showed a seal…?!!

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polaroidprincess

Hank, you're the reason i'm going to get a good grade in biology

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Shresth Arya

Honestly I think instead of Cameo being tamed by Hank. Hank should be tamed by Cameo, and buy as many cat treats as Cameo wants!

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Shresth Arya

Eating and Sex-having is love and life<3

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D.N. K.

I have a Biology exam tomorrow and these videos are saving my life

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Carla

The kittyyyyyyyy <333333333

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dov greenspan

What is the difference between Morphology and anatomy?

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Jacob Perron

Reference link is broken 🙁

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malindo64

He has a hickey?

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HARIKRISHNAN REGHU

Aah what to say.. Amazing videos.. Thanks a lot…

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Mother and Son Diary UK

you talk too fast
in the UK we call that gibberish

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Zatchooze Naut

"Horny Siberian Hamsters" should be a band name.

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Preeyoo

Nah I ain't saying she's a bowerbird
but she ain't messing with no uneven pebbles

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shaik ishaq

Nice video

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Teja Mihir

Yep saving my life too

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Preston Lau

can you please blink when you look at the camera?

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Petar Vasilev

"The only two things that matter – eating and sex" is a rather sad statement…

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User

Self-replicating whatnot

Why do you have a cage for your dog in your house? Seems kinda superfluous.

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BrokenCrayon

🙁

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mikkel larsen

It is worth mentioning that my cats are very able to open their sack of food, they are just quite direct and use their claws.

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Pyrimidal

You put. The tags. IN THE DESCRIPTION!!!!

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Popa Iancu Dan

Man keep seeing that red mark on your neck. Is it from sex or smth else? And another thing: the red mark seems to vanish along this episode. So by logical thinking, who strangled or kissed you right before thise course?

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Matias Angerami

Very good man. You MUST use Subtitules in other lenguages. That would br great

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Mari Home

Loving your video was very useful for my veterinary technician studies 🙂 thanks!

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Soulinflamez

8:12 #LetRonSmash

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chrisisboard

Want sum fuk?
No Ron

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NattKatt2010

Hello cat owners! My name is Natalie Gilbert, and I am mature student studying access to higher education in land based studies, at Hadlow college in Kent. As a part of my course, I am to design a scientific project which has given me the opportunity to gather data through this questionnaire on to how domestic cats (Felis Catus) affect the local wildlife population within the UK.
From this, I am hoping to achieve a better understanding as to what factors may influence the hunting behaviour of different domestic cats. For precise data, I have opted to ask you to complete this questionnaire for each cat you own. This questionnaire should take a total of 5-10 minutes to complete, and the data will be gathered on an anonymous and confidential basis.
Your contribution to this survey is greatly appreciated.
https://www.surveymonkey.co.uk/r/J5L6JXJ

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User

The Omens

Anyone notice the marks on his neck? Did Cameo scratch you?

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Ross Mundie

8:10, becky lemme smash, I got blue

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Saliha Potassium

Love crash course hate biology

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Kira1Lawliet

Lorenz was a member of the Nazi Party?
Well then, I guess you could say he perfected the original………..

goose step.

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Beth Albany

male hamster that survives the trip are better a surviving

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Monika Ruwaimana

8:10 you want sum fuk

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MagicalHacker

Cameo by Cameo?

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Apple Doom

8:40 u want some blue?

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Catherine Phoenix Hallam

Interesting video that makes this area simple and relevant

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Sleepy Rose

I have a question!…. can I have the cat? :3

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Pepe Julian Onziema

Can ALL behviours really be pinned to evolutionary advantages? Like sometimes its taken really far, when scientists try to explain play, or parts of psychology. Its soo long winded because of this and this, and this and this, they did this because it'd help them survive, (even though they didn't know it would) like there's no concept of consciousness. Seems like only half the question has been answered

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Shamoil Bhinderwala

Bower bird wants Becky to let him smash

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Noah Simon

I like your djembe drum!

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AleneRay

Thanks Hank! You're a better teacher than my university lecturer

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Mils yeah

That poor dog! He looks heart broken

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Retronite

So many people are here because they have a biology exam tomorrow 😂

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User

ألين.

:)?

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Ana Raluca

Hello, @CrashCourse! Why does the bower bird only collect blue objects? Does it have something to do with the fact that his eyes are also blue? Maybe females are attracted to the blue eyes and males try to emphasize this trait?

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Giuliana

Loved it

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Ayush Narayan

My tennis coach thinks that your cat thinks that if it was larger than you, it would eat you. Be careful around Cameo as proven by a dropout tennis coach, your cat is thinking at this very second about eating you.

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Clayton H

Becky plz, lemme smash.

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shaun03a

Horny Siberian Hamster sounds like a killer band name.

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레단

THAT MEOW THOUGH

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Wilber Castillovillatoro

Lol

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Wilber Castillovillatoro

Hi

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Wilber Castillovillatoro

Hi

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Wilber Castillovillatoro

Me

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Wilber Castillovillatoro

Bob

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Zharth

I hate to bring this up even, but it seems that Altruism is pinnacle argument against Jordan Peterson's claims of scripture being responsible for humans to acquire a level of morality that exists today. He literally brushes off the idea of other animals behaving a specific way for benefit of its' community/survival as "lower than consciousness", and that it's not the same. It's perfectly reasonable to hypothesize that humans simply achieved a point of self-awareness from the evolution of complex communication, and rationalized that it would be smarter to get into bigger and bigger tribes in order to completely dominate the playing field. You don't get to where we are by not respecting that natural guideline of depending on others to survive easier. After all, almost every primate species has adopted grouping properties, long before we were here. It's possible that scripture played a role in influencing it in a more strict manor in attempt to abolish the idea of death itself, but it certainly isn't to credit for why we've won the battle of natural selection vs. the animal kingdom. We now play against our own species obviously.

This video was really insightful, thank you.

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Megan Rivera

Plz tell cameo that I love her

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Marilyn Hellmuth

That’s so gross!

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Ui Ytresen

Bower birds?
wait for it … BECKY, LEMME SMASH!

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hanavh channel

can we have more videos with the cat in frame pls she helps me focus

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Patricia McGeorge

I am a linguist and have come to take our technical terms back. How dare you biologists steal our morphologies you analytical polysynthetic labiodental fricatives!

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roberto almeida

I thought he was going to say "How much junk he has" 8:08

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Mc2_E!

Adaptive behavior can lead to squirrels biting power cords, let's not forget. Adaptive behavior can have a pretty bad side.

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Martin Betancurt

Subtítulos en español por favor!!!!!!!

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jourdan p

Ahh, you talk so fast. Hard to keep up. But good info!

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蔡徐坤

Notice his neck? Might be scratched LOL

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Sharp Design

was not expecting to learn about hamster boot-knockin' today. interesting.

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gamin star

Hahahahhahahahhahaahhahahha

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Brandon Park

Faaaanks

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Brittani Hylton

l'm curious about the book you are reading in this video. I tried looking it up but I was unable to find it.

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Nabeeha Khaled

Cameo made a cameo!

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David Nzekwu

thank u

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Anika Greene

KITTY CAT

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Pari Ramchandani

u talk too fast

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Deacon Gibbs

W8 what if deadpool is a super sponge…

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Melis W

My cats reacted to the treat bag sound when they heard it on the video!

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THEOFILOS CHALDEZOS

Behaviorism vs ethology video?

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Dr. Z

0:43 How about rednecks? they're still around!

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harys_john

8:35 We should train that bird to dance like Ricardo, that behaviour will quickly be selected for throughout the species xD

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Kyle Hagerty

But my cat just rips the treat bag open

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S Kim

If eating and sexing are the two most important things in the world, what are the reasons for wolves to follow and obey their alpha? Is it because they might get the food if they belong to a group and follow the rules?

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margaux susman

The references link doesn't work.

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ty gje

Pet the doggg for Christ sake

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john tindell

Thank youuuuu

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