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PROFESSOR: All right, this is 920.
I'm Schneider, and this is the first class.
I will just talk briefly about the organization
of the class, the procedures, and the assignments.
And then the last part will just be
a talk about various approaches to study
of animal behavior and the main ones
we'll be using in this class.
So why did you sign up for 920?
Maybe because it's a HASS class.
But there are other HASS classes.
Maybe it's your schedule.
I make it at 4 o'clock to decrease schedule conflicts,
but a few of you still have them, especially
with the lab on Friday.
How many of you have a lab at this time on Friday?
Because of that, I will be posting the slides
if not before class, at least after the class.
And I will try to remember to record the classes so I
can post an mp3 file of the audio.
There won't be any video, so you won't
know what I'm pointing at in the slides,
but you should be able to make out what we said.
You probably won't hear student questions.
You will miss out on some of the discussion that way,
but you should still be able to keep up with the class.
So there are various practical reasons.
Can anyone give me a non-practical reason
for taking 920?
Why should you be interested in animal behavior?
Yes.
AUDIENCE: [INAUDIBLE].
PROFESSOR: OK, it might help you with human behavior.
Well, we're animals.
That doesn't mean I will stress animals,
but particularly when we talk-- actually
in both parts of the class when we talk about ethology, that
is fixed action patterns and instinctive behavior.
And when we talk about sociobiology-- adaptive
behavior, especially social behavior-- humans
will come up many times.
All right, anyway, why do I teach it?
Well I think animal behavior is fun.
I have done research in animal behavior,
though that's not been the main thrust of my career.
I am a neuroscientist, and I have done a lot of work
on brain anatomy and anatomical changes after brain damage.
But I like animal behavior, and I
hope that will be evident as I talk.
I will use examples from my own work
as well as from other people's work.
So it's sort of an undergraduate survey class at the beginning,
but in the second part it'll become more and more
a special topic seminar, and that's
especially true for the last part of the class, when
you guys will be giving your reports.
I've already posted on the Stellar website an assignment.
It's not due until the Wednesday before the Thanksgiving break.
So you have a lot of time.
You will make a PowerPoint slide presentation,
and then you will prepare yourself
to give that presentation orally.
Your slides will include notes that
will give me more detail about what you would like
to talk about, even if you don't get to talk about all of it.
In the notes section-- whenever you do PowerPoint,
there's a note section that is not
shown during a presentation.
But you can make lots of notes, and that gives me
a better idea of the research you've done.
OK, so read that assignment.
We will let you know if we decide
to make any alterations after talking
with students and with each other.
Make sure you check that Stellar site regularly.
I will try after every class to make sure I post the slides,
but before the class, I will usually post study questions.
Those questions cover class sessions,
and they cover readings that will be assigned.
Usually they don't cover readings
that are listed as supplementary readings.
If you don't have time to do the supplementary readings,
it's all right.
If it's of particular interest to you, you should do them,
and it will help you understand the material.
OK, so there's just two small textbooks.
I choose a smaller book in animal behavior
so that we have time to do other kinds of readings.
And you'll be reading quite a bit of Konrad Lorenz
and a little bit from Niko Tinbergen,
two of the classical great ethologists.
And I think you'll appreciate their observations
when you get them directly.
We also will see-- especially Lorenz-- in videos
that we show in class.
There will be quizzes and homework.
And almost always, these will be on Wednesdays.
That is if it's homework, it will normally
be due on a Wednesday-- once in awhile on a different date,
but the quizzes I will try to keep limited to Wednesdays.
We don't always have a quiz.
That is, in a week where we have homework,
I might decide not to give the quiz,
but we'll always let you know in advance.
OK so first we'll be going through key concepts
emphasizing ethology.
And we'll talk about what that is today.
The readings will be in the Scott textbook,
but they'll also be, as I mentioned, from other readings.
And then we'll see some videos relevant to ethology.
And then, after mid-term we'll be talking about sociobiology.
That will be mentioned today as well.
And we'll have readings.
The readings will mainly be a small book by John Alcock.
It's called The Triumph of Sociobiology,
which is a very apt title.
It was written a few years ago, but in fact, it
does express well how sociobiology
has become a major force in studies of animal behavior.
And I will go over some of the key ideas of E. O. Wilson, some
of them directly from his writings.
These are just examples of specific topics.
Most of you have seen these kinds of things
if you've had any encounter with animal behavior.
Some of them might sound a little bit--
we use specialized language to talk about behavior,
and it's a little different from what you're used to
from just talking about human behavior.
We talk about eating in animal behavior-- talk about feeding,
and foraging, and stalking, and prey capture, and things
like that.
We talk about anti-predator behavior.
Do humans show anti-predator behavior?
You bet they do, but we don't usually
call it that, OK, since we don't have too many tigers
and lions roaming the streets around here anymore.
Terms for sexuality are used, of course, in human behavior
and in animal behavior, and that will
be a little more familiar to you.
But more specialized terms will occur there.
These are examples.
You can read those other things I listed.
These are examples of questions and concepts that will come up.
We'll talk about what instinctive behavior is,
what a fixed action pattern is.
Fixed action patterns is an ecological term
for instinctive behavior, but it's actually fairly complex.
But there's a regular pattern in most of these behaviors.
They're not the same as reflexes,
and we will make that very clear in the class.
Why do some animals migrate halfway around the Earth just
to mate and raise young?
What is the evolutionary origin of kissing?
Do animals kiss?
Yes, they do.
And it has its origins in animal behavior,
and it's been traced pretty convincingly.
Why do animal behaviorists engage in gene counting?
Why would they have to do that?
It's related to a question down here-- the last one--
why might a worker ant behave differently
depending on whether its mother, queen, is promiscuous
or monogamous?
It makes a difference.
They behave differently.
The question is why?
That why question has different levels.
It can be an approximate question--
that is, what stimuli is he responding to?
What are the mechanisms of the behavior?
Or it could be what we call an ultimate question, which
is not a theological term here.
Ultimate question in this class simply means,
what is the evolutionary significance?
What makes it adaptive for the animal
to behave in the way he does?
So its the major issue in sociobiology.
What's a Darwinian puzzle?
Behaviors appear that are difficult,
at least at the beginning, to explain
in terms of Darwinian evolution.
We can't figure out how they're adaptive, so they're a puzzle.
We call them Darwinian puzzles.
Why is the killing of infants adaptive in some animals?
How could that ever be adaptive?
You should be able to explain that,
and we will do that in the class.
Some of your projects will be on topics
we cover in the class, but not all of them.
In fact, most of them will not be directly on any details
that I bring up in the class.
But I do expect you, when you're dealing with the animal
behaviors that you want to discuss in your reports--
I expect you to interpret them in terms of the principles
and concepts of ethology and sociobiology
that you learn in the class.
What do I expect outside of class?
Readings, study questions-- I will post these study questions
for every class.
I want you to try to answer them, if possible at least some
of them before the class.
I might just ask you, sometimes, some of these questions,
and I might not tell you who I'm going to ask.
Otherwise you might say, well I might as well be passive.
I can read it later.
But I find that when you say that, it means usually
you won't read it.
You'll try just to get it, what I say in class,
and hope that gets you by.
No, you will do much better if you read.
So read just for key concepts.
There will be a lot of examples, details of animal behavior.
But at least try to get the key ideas,
and that's what I'll be emphasizing.
I will try to.
If you think I'm talking about some detail that's
not a key concept, you let me know.
Maybe some aspects of animal behavior
I just find fascinating.
OK, I posted, and some of you seen
this-- you've been looking at the Stellar site.
I posted, quite a while ago, the first reading from a book
by Jim Corbett.
Corbett was not an ethologist, and he was not
a sociobiologist.
He was actually a hunter.
He was often hired to track down and kill man-eating tigers
and lions in Asia and Africa.
He was probably the best of hunters
that did that kind of thing.
And he was also an amateur naturalist.
And he's written some things about his hunting methods.
And I've posted some things that display his knowledge
about what he calls sensitivity to the jungle,
the signs of the jungle.
A good naturalist learns those kinds of things.
So please read that.
You'll be asked about it in the first homework.
I've written the first homework, but I
will wait for feedback from the teaching assistants
before I finalize that.
It won't be due until a week from today.
So for the next session, I posted the first chapter
of Graham Scott, in case you don't have it,
but I won't be posting later Scott readings,
since you're supposed to get that book.
But I did post Chapter 11 from Tinbergen's book--
his semi-popular book, Curious Naturalist.
And I posted study questions already on those readings,
as well as some for today's session.
OK, these are things we've talked about.
So how have we learned about animals?
Of course, many of you have pets,
and some of your hobbies concern animals.
You've encountered animals in the natural world
or you've gone to zoological parks.
You've certainly encountered them in some films.
But we also pick them up from common beliefs,
what we call folklore about animals.
There's a long history about that.
You can pick up in a library these books
that appeared in the Middle Ages that
are called the medieval bestiaries.
They portrayed animals in a fantastic way,
and the reason was they heard stories
that came from observations of African and Asian animals,
that they didn't have in Europe.
And these were stories in Europe,
and they-- because they were second, third,
and fourth-hand stories, they were often
greatly exaggerated and distorted.
And it was commonly believed that in the Middle Ages,
people just didn't have any accurate
ideas about animal behavior at all.
But recent scholarship in that field
has shown that even though that may have been common folklore,
it was not generally representative of what
was known to people who were really interested in details
of animal behavior-- even in the Middle Ages.
And there was a lot more known.
Why would you expect people to know about animals
in some realistic terms, even a long time ago, even
before the Middle Ages?
Why would you expect it?
Well, think of farming.
If you're going to raise animals, or use animals
for work, you have to understand something about their behavior.
Dogs have been domesticated probably well
before people could write.
OK, so it really goes back into pre-history.
And certainly people knew a lot about the domesticated wolves
that we call dogs.
Stories and folklore that still abound, especially
in cities, concern rats.
And whole books have been written about that.
I have one of them here, called More Cunning Than Man.
It's basically stories about rats.
It's not written by a scientist.
He's interested in reports, newspaper reports,
what people say, the stories they pass on.
And the stories about rats are most amazing.
They're stories about giant rats that when you hear the story,
you'd swear the rat must be as big as a dog at least,
and stories about the incredible harm.
And the fact is they have caused incredible harm.
That's one reason rats are often hated and feared.
Now, of course, in a department like this,
they're used in the laboratory.
We don't look at rats that way at all.
But if you're in New York, and you're in a poor area,
and your building is infested with rats,
then it's a different story.
They have attacked people, damaged them at night.
But probably the things that have
made rats the least popular is the diseases
they have spread or have been in some way
responsible for the spread of diseases, like Chagas' disease.
The book covers a lot of that.
And there's quite a few diseases like that
that rats have been involved in spreading.
The one that is commonly attributed to rats
is the diseases that caused the worst pandemics
in human history.
What am I talking about?
What were the worst pandemics that
killed a third of the population of Europe, that killed probably
more than 30 million people in Asia, large numbers in Africa?
What do we call that disease?
The plague-- bubonic plague-- it was a horrible disease,
and there was no way to cure it.
So people tried various ways.
They had great fear of it.
Many people thought the world was coming to an end
during that period, when they saw everybody in a building
die.
Children invented nursery rhymes in their play,
singing about Ring around the Rosie, a pocketful of posies.
Why were they putting flowers in their pocket?
To counter the smell of death.
We make it a game now with children.
You know, the game ends, "We all fall down."
That was dying, but children turned it into a game.
So how were rats involved?
What really-- now we know it's a certain organism that
causes it, but what was the vector?
Was it rats?
AUDIENCE: Was it their fleas?
PROFESSOR: Excuse me?
AUDIENCE: Was it their fleas?
PROFESSOR: Yes, it was the fleas on the rats.
And rats died.
And when they died, they lost body heat.
Children would sometimes play with the dead rats.
And as the body heat dropped, the fleas
would leave the dying body, and jump on anything--
any warm, live body which often was
children or other human beings.
And it was the fleas that were spreading the disease.
But people didn't know that.
And so they blamed various things.
Some areas, they killed every dog,
because they blamed dogs, or cats,
or they blamed-- if you're in one country,
you blame the neighboring countries.
Or in many cases, it was blaming an ethnic group,
or blaming Jews.
It was horrible, because they were desperate and ignorant.
Of course, the way that disease has been controlled
is through better hygiene and better knowledge.
Anyway, I just point out here not
all rodents are hated as much as rats.
We still have hamsters and gerbils,
which are cute, little rodents and used as pets, as well
as in some research.
And we know we use animals for various things,
so we know about them that way.
We use them for meat.
We use them to make leather.
We use them in sports-- for hunting and to help us hunting.
We don't hunt dogs.
We use dogs to hunt other animals.
They're used in some religions, as you know.
But we use them in science.
What are they in science?
They're stand-ins for humans, usually.
We use them as models.
Of course, the most popular animal now for that
is the mouse, because of the genetic variance and the ease
of creating specific models of pathologies by altering genes.
But when we're using animals, we're
often depending on behavioral tests.
And what are we studying?
We're studying a human disease, but to understand
what we're really doing, we need to know something
about animal behavior.
And unfortunately, a lot of people using animals
all the time don't know much about animal behavior.
We also know about them from groups like the Humane Society,
and the Animal Rights Movement.
It's human oriented in a very different way,
sometimes with very anthropomorphic thinking.
Sometimes it's more anthropomentism--
thinking that their thinking must be like our thinking.
Their feelings must be like our feelings.
I'm not arguing that they're not.
We know they have nervous systems,
if they're mammals, that are very similar to ours.
But we think of them commonly as being conscious,
and I would argue that that's probably the case.
It's not the same as our consciousness,
but we know it arises in nervous activity.
I'm not saying we can explain it by nervous activity,
but it's correlated with it, and animals have that, too.
Different religions have very different attitudes,
so I'm sure some of you that follow different religions,
if you do know some of these extremes-- on the one pole,
you have Judaism and Christianity that
believe in control of Nature, dominance of Nature,
and so forth.
And then you have examples like Jainism,
where they are totally pacific and don't
believe in harming any life.
And we've had examples of that in West,
too, like Albert Schweitzer was like that.
But in this class, we take a basic science approach.
It will be descriptive and experimental.
And we will use the perspective of evolution
throughout most of the class.
Scientific work has focused on individual organisms.
We'll talk about that first.
It's focused on societies, so we'll talk about that next.
But it also has other focuses, like on the habitat and species
in the habitat, and the interactions of all living
things, with the nonliving things
in that particular habitat-- interactions with the climate,
the topography, and so forth.
And then there's sciences that focus on a single species
or group of species.
You have mammalogy, for example, that deals generally
with all aspects of mammals, including behavior-- behavior,
anatomy, physiology, and so forth.
Or primatology-- dealing with primates
as a group-- a major field.
But we don't call it primatology within, say,
experimental psychology, generally.
But it's used that way among anthropologists and others.
And then, of course, we have the amateur naturalists--
disciplined hobbyists.
And that's important in this field,
just like it has been in astronomy, because they've
made major contributions.
In fact it was amateur naturalists
that led to the initial discoveries that
led to the whole development of ethology.
So first of all, focus on the individual organism--
in America it was called, in the last century,
comparative psychology.
It's sometimes still called that.
The real focus was on humans, but they used animals.
The main type of study in the heyday of the field,
the middle of the last century, was studies of learning.
And it still is in many labs.
The animals used are mostly rats and mice
as models for studying learning.
And it's interesting that that was not the approach
to animal behavior in Europe at that same time.
Why do you think that was?
Well, think of what was unique about what
was going on in America.
What was our approach to education?
The idea was that we start life with pretty much a blank slate.
And by education we can create individuals,
we can influence individuals and various ways.
Our children can become whatever they can become, just
through learning, through making the effort.
You can do anything if you just put your mind to it.
How many of you have heard that from your parents?
Most of us.
Did you ever hear, "Well, you behave that way because you've
inherited that behavior and that's your instinct?"
No-- if you were in Europe, it was very different.
But that was the belief in America.
It was wrong, but it was also very beneficial,
because what did it lead to?
It lead to universal education-- arguably the best in the world.
The country that tried to educate everybody
regardless of origins, regardless of wealth--
and at the time that developed, it was unique.
And we're not the only country that does that now,
but at that time it certainly was.
And it was encouraged in its popularity
by ideas of educators.
I use John Dewey as an example.
His dates are 1859 to 1952.
He was very influential.
The emphasis was on practicality--
on shaping the individual through learning--
very important in the development
of educational systems in America.
And either implicitly or explicitly,
they believe that we start life with a blank slate.
And that was what came out of that in psychology-- including
this comparative psychology I'm talking about--
is that same idea.
They focus their whole effort on learning, almost nothing
on instinctive behavior, unless they
wanted-- that was the realm of the physiologist, who
studied reflexes.
They didn't study more complex, instinctive behavior
that we'll be talking about in this class.
And so theorists arose who tried to come up
with a system of learning to explain all human behavior.
You've all heard of B. F. Skinner.
You've probably heard of Thorndike, inventor
of various puzzle boxes and describer
of instrumental learning.
So for a long time, you pick up a book on learning,
and it was about instrumental learning
and classical conditioning-- the two main kinds of learning.
Are they?
Hardly-- but in fact, that's what was taught,
and it was a major part of psychology
in the middle of last century.
In fact, that persisted for some time--
the second half of the last century, 20th century.
But in Europe, it was very different.
In Europe, you had the development
not within psychology, but within the field
of zoology-- part of biology.
Zoology is the field wherein ethology,
the study of natural behavior patterns, developed.
I will take Conrad Lorenz, leader in that field,
from his book, The Foundations of Ethology.
He defined ethology this way-- it's the discipline which
applies to the behavior of animals and humans,
all those questions asked and methodologies
used as a matter of course in all the other branches
of biology since Charles Darwin's time.
Ethology, or the comparative study of behavior,
is based on the fact that there are mechanisms of behavior
which evolve in phylogeny-- that is,
among different animals of different types--
exactly as organs evolve, so that the concept of homology
can be applied to them, as well as to morphological structures.
The origins of this approach was in ornithology, and in fact,
in amateur ornithology.
And these are the two people that we attribute
the initial discoveries to-- Charles Otis
Whitman in America.
These were the dates of his publications.
He kept a collection of doves and pigeons in aviaries,
and he studied them.
And then Oscar Heinroth, director
of the Berlin Zoo-- his publications 1910, 1928, 1930.
He studied the rich collection of waterfowl
kept at the Berlin Zoo.
So they were both studying captive animals, captive birds,
but very different kinds of birds.
And they independently discovered
that motor patterns, just like morphological characteristics,
can be inherited, can be homology
across different species.
But Darwin knew a lot of this already.
And in his book, he talks, for example, about dog behavior.
If you look at this picture, compare this picture
with this picture.
What's different about these two dogs?
You can tell right away this is a friendly dog,
and this is not.
This is an aggressive dog.
How many of you can recognize that immediately?
Oh, come on.
Surely you have pet dogs and you know that difference.
This was what your dog looks like when he's greeting you
when you've been gone for a long time.
And he's greeting you-- especially his master coming
home.
This is a dog-- usually when they
act like this towards humans, it can be dangerous.
OK, but they certainly act like this
when faced with other dogs.
And Darwin saw these patterns, because he could recognize them
in one dog after another.
These were inherited patterns of behavior.
They were instinctive behaviors.
And he applied that concept to human behavior as well.
For example, in his book-- this is
from his book, The Expression of the Emotions in Man
and Animals, as were these pictures.
Here he's showing various pictures
of human emotional expressions.
Our emotional expressions are instinctive-- patterns
that are the same across all of us, across various races.
All Homo sapiens show these same patterns.
Yeah, you say, oh, but the Japanese
don't make the same expressions when they're happy, or this
or-- oh yes, they do.
But then in addition, of course, we
develop certain ways of using expressions
for different meanings.
Well, ethology has been applied to humans, and not
just by Darwin.
But as Lorenz pointed out, the proof
that humans really had instinctive, inherited behavior
patterns-- though it was suggested by Darwin,
and he was accurate in his descriptions--
but the real proof came from Eibl-Eibesfeldt.
Irenaus Eibl-Eibesfeldt wrote a large book
called Human Ecology in 1989.
It's available in the library.
I have a copy in my office, and if you're
interested in how these ideas apply to humans,
you will find them described there.
I'll say a little bit more about human ethology
next time, just so you'll know how Eibl-Eibesfeldt
went about proving to anybody who studied his book that he
was right about this.
More popularly, we know about body language,
which became a really popular craze for awhile some time ago.
Now it's sort of entered the common parlance,
but that is all based on these instinctive patterns.
We know about neuroethology.
We'll say a little bit about that in class,
but it's not primarily a class on neuroscience,
so I won't stress it.
But I will say that studies of the brain
have led to studies of how instinctive behaviors are
controlled.
And brain studies have been used to distinguish
different kinds of aggression, for example.
But they're all things already known to ethologists.
Obviously, if patterns are very different,
then they're expressed differently in brain activity.
OK, now if the focus is on societies and social behavior,
then we're usually not talking about ethology--
though I should say there's a lot of overlap
between ethological studies and sociobiological studies.
But the main emphasis of the work in sociobiology
has been different.
Edward O. Wilson at Harvard was the one
who invented the term sociobiology,
though it had been used before, for example, by C. Judson
Herrick, a comparative anatomist who
wrote a book on human nature and behavior.
But it was very speculative, and if you read what he actually
says about sociobiology, it was very different
from E. O. Wilson, because he never even refers to Darwin.
So it was really Wilson that brought--
he wrote basically a review of many different aspects
of social behavior in many different species,
and in his last chapter, it was about humans.
And that is what caused him so much trouble.
There was actually a revolt along humanists
and even scientists here at MIT, that tried to-- they
wanted the whole field suppressed.
I know that's hard to believe, that in recent years
that actually happened.
But I was already at MIT when that was happening.
I met E. O. Wilson.
I like Ed lot, and I had also, like he did,
trouble understanding why people were getting so upset.
Konrad Lorenz has been attacked, also,
because he applies ethology to human behavior, too.
You see a lot of people who do not want any of this stuff
that we apply to animals to apply to humans.
It becomes a political thing.
And I will just urge you to keep politics
separate from the science.
But that's what people were doing.
And at the time this came out, ideologies
were being argued a lot.
Socialist ideologies, communist ideologies
believe strongly in not anything inherited.
And for very different reasons than, say,
what we talked about in the development of education
in America-- very different approaches.
But it led to a more vehement opposition to sociobiology,
and we'll go through that history
in the middle of the class when we
start talking about sociobiology.
It's very different from cultural anthropology.
It's very different from sociology.
In fact, sociologists have been very
resistant to applying to the application of Darwinian ideas
and evolution to social behavior of humans.
Many cultural anthropologists are the same way.
It's culture that determines our behavior, not biology.
That's almost a quote from some of these people.
I hope you don't end up believing that.
But anyway, here's-- from E. O. Wilson's book,
I just wanted to show you how he conceptualized this,
just so you can see it.
Here was the way he conceptualised
these fields of study of behavior in 1950.
He has ethology and comparative psychology in America.
Ethology in Europe is quite separate,
which they were at that time.
Here he has the beginnings of sociobiology,
but the word was not being used in 1950.
It was part of behavioral ecology, just part of ecology,
and that was closely connected to population biology.
So that was the close link, just like over here
on the other side, you have integrative neurophysiology
closely linked to cell biology.
In the middle you have these behavioral fields-- ethology
and comparative psychology.
OK, so then 1975 is when the term sociobiology originated.
The ties to population biology were made explicit
by E. O. Wilson.
Ethology and biopsychology or physiological psychology--
it went by various names-- now it's
often just neuroscience and behavior,
or behavioral neuroscience-- had become a little more closely
linked.
But I think he's overly optimistic,
because in 1975, those two fields were still
largely separate in the way they were
carried out-- the work being done.
And here's the way he envisioned it back in 1975 and '80
when he published his books-- he saw
sociobiology increasing, these fields decreasing.
It hasn't actually happened quite like that.
What has happened is that both ethology
and experimental studies of animal behavior in America,
including a blurring, have become much more integrated
with ideas of sociobiology.
In fact, the most recent books in animal behavior--
I was reading them this summer-- they go to great lengths
to integrate, almost discuss in a pretty seamless way,
sociobiology and ethology, for example.
What I didn't like about them is that they start out
with all this gene counting, and you
feel like you're studying not animal behavior
but some mathematical field.
It's a little hard to describe, but I
didn't feel that it was very successful.
If you don't know much about animal behavior
in the first place, you'll find it really dull.
So I don't take that tack, but you will learn the same things.
OK, if you focus on the habitat and the species
a habitat supports, then you're talking about ecology,
and you can find the field of behavioral ecology talking
mainly about behavior.
If you focus on a single species,
then-- we've already mentioned this--
you can talk about primatology or cetology
if you're just studying cetaceans,
entomology if you're studying insects.
If you're looking in mammalogy, though, you'll
find topics you simply don't find
in ethology or physiological psychology.
Running speeds of land mammals, submersion times
of aquatic mammals and amphibians,
tunnel structures of burrowing mammals,
the composition of milk in various mammals,
the biomass of animals, the total mass
of all animals in a habitat or in a region,
or the mass per unit area on the Earth's surface--
you don't find those in these other behavioral books,
but you do find them in mammalogy books.
And then we discuss the amateur naturalists,
and that's where I end.
And I will tell you a little bit more
about these topics at the beginning of the next class.