[Paleopsych] NYT: The Animal Self

[Premise Checker]

The Animal Self
http://select.nytimes.com/preview/2006/01/22/magazine/1124993979623.html

By CHARLES SIEBERT

A big-city aquarium after closing hours is an eerie, spectral
place. With the lights turned down in the empty viewing galleries,
the luminous dioramas of the different fish fairly swell against
your senses, rendering you the viewed and startled captive, adrift
in your own natural medium, in a literal suspension of disbelief.
"Help yourself," Sal Munoz, a night-shift biologist at the Seattle
Aquarium, told me one night this past fall, pointing to the huge
12-foot-high glass tank in which the subject of my specially
arranged private encounter that evening resided: a 70-pound giant
Pacific octopus named Achilles.

I was first introduced to Achilles earlier that day by Roland
Anderson, another scientist at the aquarium, and I was still having
trouble with Anderson's description of him as "a young, pretty
male." There are, as fellow life forms go, few as deeply alien - in
both substance and appearance - as the giant Pacific octopus.
"G.P.O." adults can weigh more than 100 pounds, and yet all of
their throbbing, multi-tentacled mass can pass like water through a
drain pipe no bigger in circumference than an apple, just wide
enough to accommodate the octopus's cartilaginous beak, its only
solid body part. These creatures look, at rest, like cracked
leather discards from a handbag factory; in motion, like wind-swept
hot-air balloons in severe deflation distress, with no one at home
in the balloon's gondola but for a pair of unsettlingly knowing
black eyes.

It was those eyes more than anything that I had asked Anderson for
special permission to come back and stare into on my own. Just me
and Achilles. With no one else around to make me self-conscious for
engaging in a protracted stare-down with an octopus. For reading
impossible complexities into his muffled side of the conversation.
For tapping my fingers on the glass in hopes of getting Achilles
riled. For behaving, in short, in a way that even I, an inveterate
lingerer before zoo enclosures and fish tanks, would have
considered preposterous had I not heard Anderson's real-life
octopus stories earlier that day.

Anderson told me that he and his staff started naming the G.P.O.'s
at the Seattle Aquarium 20 years ago. Not out of cutesy
sentimentality. Anderson, a longtime marine biologist and the son
of a sea captain, is not given to that sort of thing. It was, he
said, because they couldn't help noticing the animals' distinct
personalities. G.P.O.'s live about three or four years, and the
aquarium typically keeps three on the premises - two on display and
one backup or understudy octopus - so there have been a good number
of G.P.O.'s at the aquarium over the past two decades. Still,
Anderson had little trouble recalling them: Emily Dickinson, for
example, a particularly shy, retiring female G.P.O. who always hid
behind the tank's rock outcroppings, or Leisure Suit Larry, who,
Anderson told me, would have been arrested in our world for sexual
assault, with his arms always crawling all over passing
researchers. And then there was Lucretia McEvil. She repeatedly
tore her tank apart at night, scraping up all the rocks at the
base, pulling up the water filter, biting through nylon cables, all
the parts left floating on the surface when Anderson arrived in the
morning.

One particularly temperamental G.P.O. so disliked having his tank
cleaned, he would keep grabbing the cleaning tools, trying to pull
them into the tank, his skin going a bright red. Another took to
regularly soaking one of the aquarium's female night biologists
with the water funnel octopuses normally use to propel themselves,
because he didn't like it when she shined her flashlight into his
tank. Yet another G.P.O. of the Leisure Suit Larry mold once tried
to pull into his tank a BBC videographer who got her hand a bit too
close, wrapping his tentacles up and down her arm as fast as she
could unravel them. When she finally broke free, the octopus turned
a bright red and doused her with repeated jets of water.

Just across from Achilles that night was another G.P.O. named
Mikala, their two tanks connected by an overhead, see-through
passageway, the doors to which were closed. Mikala was a recent
replacement for Helen, who had just been released back into the sea
after a failed attempt by the scientists to mate her with Achilles.
Anderson told me that they had left Achilles and Helen together in
the same tank for a week, but, he said, "there wasn't any
chemistry." In the coming months, they would be trying the same
routine with Mikala, to see if anything clicked.

At one point I decided to absent myself from Achilles' stare and
walk around to the far side of his tank to look at Mikala in hers.
Standing in the narrow space beneath the overhead passageway, I
found her sound asleep, mushed between her tank's outer glass and
some craggy rocks. I thought about tapping the glass to see if I
could stir her, but decided to leave her be. When I turned around,
Achilles was right there behind me, bobbing against the glass,
bright red, his black eyes opened wide.

"How do we even define what an emotion is in an animal?" I recalled
Roland Anderson asking earlier that day. "And why do they even have
these different temperaments?"

It was back in 1991 that Anderson and Jennifer Mather, a
psychologist from the University of Lethbridge in Alberta, Canada,
first decided to undertake a joint personality study of 44 smaller
red octopuses at the aquarium as a way to begin to codify and
systematize what they thought they had been observing. Using three
categorizations from a standard human-personality-assessment test -
shy, aggressive and passive - their data would ultimately show that
the animals did consistently clump together under these different
categories in response to various stimuli, like touching them with
a bristly test-tube brush or dropping a crab into the tank.

"The aggressive ones would pounce on the crab," Anderson told me.
"The passive ones would wait for the crab to come past and then
grab it. The shy animal would wait till overnight when no one was
looking, and we'd find this little pile of crab shell in the
morning."

Anderson and Mather's resulting 1993 paper in the Journal of
Comparative Psychology, entitled "Personalities of Octopuses," was
not only the first-ever documentation of personality in
invertebrates. It was the first time in anyone's memory that the
term "personality" had been applied to a nonhuman in a major
psychology journal.

Scientists are not typically disposed to wielding a word like
"personality" when talking about animals. Doing so borders on the
scientific heresy of anthropomorphism. And yet for a growing number
of researchers from a broad range of disciplines - psychology,
evolutionary biology and ecology, animal behavior and welfare - it
is becoming increasingly difficult to avoid that term when trying
to describe the variety of behaviors that they are now observing in
an equally broad and expanding array of creatures, everything from
nonhuman primates to hyenas and numerous species of birds to water
striders and stickleback fish and, of course, giant Pacific
octopuses.

In fact, in the years since Anderson and Mather's original paper, a
whole new field of research has emerged known simply as "animal
personality." Through close and repeated observations of different
species in a variety of group settings and circumstances,
scientists are finding that our own behavioral traits exist in
varying degrees and dimensions among creatures across all the
branches of life's tree. Observing our fellow humans, we all
recognize the daredevil versus the more cautious, risk-averse type;
the aggressive bully as opposed to the meek victim; the sensitive,
reactive individual versus the more straight-ahead, proactive sort,
fairly oblivious to the various subtle signals of his surroundings.
We wouldn't have expected to meet all of them, however, in
everything from farm animals and birds to fish and insects and
spiders. But more and more now, we are recognizing ourselves and
our ways to be recapitulations of the rest of biology. And as
scientists track these phenomena, they are also beginning to
unravel such core mysteries as the bioevolutionary underpinnings of
personality, both animal and human; the dynamic interplay between
genes and environment in the expression of various personality
traits; and why it is that nature invented such a thing as
personality in the first place.

Animal personality studies are only the most recent manifestation
of the inroads that science is now making into what has long been
uncharted terrain: the very inscrutability of our fellow creatures
that has, from the dawn of human consciousness, both begotten and
bound us to our wildest imaginings about them. All sorts of
research has been done in recent years revealing various aspects of
animal complexity: African gray parrots that can not only count but
can also grasp the concept of zero; self-recognition, empathy and
the cultural transference of tool use in both chimps and dolphins;
individual face-recognition among sheep; courtship songs in mice;
laughter in rats. This is no longer merely the stuff of
anthropomorphism or isolated anecdote. As Jaak Panksepp, the
neuroscientist who first discovered rat laughter, has pointed out:
"Every drug used to treat emotional and psychiatric disorders in
humans was first developed and found effective in animals. This
kind of research would obviously have no value if animals were
incapable of experiencing these emotional states."

Now, with the emergence of animal-personality studies, we are
gaining an even fuller appreciation not only of the distinctiveness
of birds and beasts and their behaviors but also of their deep
resemblances to us and our own. Somehow, through the very creatures
we have long piggybacked upon to tell stories about ourselves, we
are beginning to get at the essence of that one aspect of the self
we have long thought to be exclusively and quintessentially ours:
the individual personality. The octopuses' garden is proving to be
quite deeply and variously shaded indeed.

Appropriately enough for a newly emerging psychological science,
the world's first Animal Personality Institute, or A.P.I., is still
more of a proposition than a physical place. Indeed, outside of a
newly established Web site with a flashy bright blue logo, A.P.I.'s
only visitable locale can be found on the third floor of the
psychology-department building at the University of Texas in
Austin, in the small, book-crammed office of A.P.I.'s founder, Sam
Gosling, a London-born, 37-year-old professor of psychology. "This
here is my collection of animal-personality literature," Gosling
told me one afternoon in October, pointing to a long row of thick
blue binders along the top shelf of his office's bookcase,
including animal studies from fields as diverse as agricultural
science, anthropology, psychology, veterinary medicine and zoology.
"We're trying to scan them all and make them available, because
part of. . . I mean.. . ."

A tall, gaunt figure whose flowing locks, untucked striped shirt,
slightly flared bell bottoms and ankle-high leather boots give him
the appearance of a 60's-era British rock star, Gosling is given to
switching gears midsentence, his active mind going in a number of
directions at once. "Part of what we're trying to do here," he
continued, "is create a field."

Gosling, who often refers to himself as "a bit of a fraud," being
what he calls "a personality expert who knows very little about
actual animals," was a young graduate student in psychology at the
University of California, Berkeley, when he first came upon
Anderson and Mather's paper on octopus personality. It was not at
all an area of research he expected to be poking his nose into,
having originally attended Berkeley to pursue a degree in human
personality. But in the course of one of his first seminars, he
suddenly found his thoughts going in an unlikely direction, what he
now refers to as his "reductio ad absurdum moment."

"It was a basic seminar in human personality," he recalled. "We
were considering the question of what is personality. And I
thought, O.K., let's try to push it to its limit. To find out what
personality is, let's start by taking what's clearly outside that
category and discover what's different about that. Let's take
animals. They obviously don't have personality. So then I thought,
O.K., if animals don't have it, then what is it that makes them not
have it, and I couldn't come up with an answer."

A standard answer, of course, is that animals do not, as far as we
know, reflect upon and argue with their experiences, emotions and
behaviors in the way that we humans do. They do not possess, in
other words, that dynamic, self-reflective, internal dialogue the
very outcome of which is, many scientists say, our personality. Of
course, whether or not self-knowledge is truly a defining
characteristic of personality is a question scientists disagree on,
as they do about much else in the field. Indeed, the whole notion
of personality is one that we only began trying to measure and
codify in the past century. Personality theory started showing up
in the writings of Ivan Pavlov and Sigmund Freud as a somewhat
vague, broadly drawn concept. It has only been in the last 60 years
or so that the modern science of human personality began to emerge,
a system of assessing distinct personality traits that has its
roots in World War II, when the U.S. government assigned to the
Office of Strategic Services (the forerunner of today's C.I.A.) the
task of identifying which individuals had the right traits to be
spies. A number of different personality-mapping methods and
traits-assessment tests have been developed over the years, all of
them pivoting around the principle that certain traits can be
consistently observed in individuals across time and different
situations. The most widely applied test today uses the categories
defined by what is known as the Five-Factor Model (F.F.M.):
openness, conscientiousness, extroversion, agreeableness and
neuroticism. Under each of these broad dimension headings are
so-called clusters of recognizable traits: an extroverted person,
for example, is more sociable, outgoing and assertive; a neurotic
one, more anxious, moody and stressed.

Gosling, however, was intent on exploring personality at its most
rudimentary level - below the radar, if you will, of human
consciousness. Applying some of the very same personality
assessments that we use on humans, he wondered whether we could
observe in animals essential traits like fearfulness,
aggressiveness, affability or calmness, traits that can exist
outside of cognition and yet are clearly and repeatedly apparent in
varying measures in different individual animals within a given
species.

Does one duck, in other words, behave consistently differently from
another duck, over time and across situations? If so, why doesn't
that meet the definition of personality as we apply it to
ourselves, regardless of the presence or absence of self-awareness?
In a sense, Gosling was posing a psychologist's rendition of that
old philosophical query about whether the tree that falls in the
forest, miles from anyone's ears, still makes a sound. That is, if
an animal behaves in distinctly consistent ways but isn't fully
cognizant of such behaviors, can the behaviors still be aspects and
indications of its personality?

One way Gosling set about answering that question was to focus on a
colony of 34 hyenas being kept on the Berkeley campus by Steve
Glickman, a professor of psychology. With Glickman's blessing,
Gosling asked four caretakers of the colony to independently fill
out questionnaires about each animal, using a modified version of
the F.F.M. test. He soon found that the caretakers' assessments had
the same level of agreement, or "convergence," as is found in
assessments done on humans, with such distinct human dimensions as
"excitability," "sociability," "curiosity" and "assertiveness"
being repeatedly observed.

Gosling then reviewed 19 different previous behavioral studies of
nonhuman species through the same F.F.M. framework and found a
similar recurrence of those dimensions across a surprisingly broad
spectrum of species. Among the traits remarked upon were such
things as "opportunistic, self-serving" behavior in certain vervet
monkeys; "emotionality" in rats; "fear avoidance" in some guppies
and "extroversion" in others; and, in Anderson and Mather's 1993
paper, both "boldness" and "avoidance" in octopuses.

"The evolutionary continuity between humans and other animals
suggests that some dimensions of personality may be common across a
wide range of species," Gosling wrote in the resulting paper he
published in 1999 in the journal Current Directions in
Psychological Science. "Scientists have been reluctant to ascribe
personality traits, emotion and cognitions to animals, even though
they readily accept that the anatomy and physiology of humans is
similar to that of animals. Yet there is nothing in evolutionary
theory to suggest that only physical traits are subject to
selection pressures."

Gosling told me that his seminar adviser thought the whole thing
sounded a bit "goofy" at first. Some of his fellow students,
meanwhile, were irked at him for trying to bring the field of
personality to disrepute, as Gosling put it, by studying silly,
trivial, frivolous stuff. The major sticking point, of course, was
his insistence on using the obviously loaded word "personality," a
choice that he admits was purposefully provocative.

In some quarters, the term still rankles. "Personality ratings have
been done with chimps where you can see in them intimations of
human characteristics," says Jack Block, an emeritus professor of
personality psychology at Berkeley. "Now, where you want to take
that, I don't know. Even with chimps, it is a big extrapolation
from them to us. But personality in fruit flies or octopi? Heck,
no. All living organisms do react to pain and seek what they have
developed to want in terms of food or mating. But they cannot
manifest the complexity of responses that human beings can."

John Capitanio, a psychology professor at the University of
California, Davis, who does extensive behavioral studies with
rhesus monkeys, is more willing to extrapolate. "Animal
behaviorists or behavioral ecologists are mostly interested in what
the animal is presenting them with in terms of behavior," he told
me recently. "And yet the behaviors exhibited are not dissimilar
from our own, and that's what causes us to infer these personality
characteristics. Now do they really exist in animals? I think the
answer is yes, they do in some form."

In many of his early talks, people would ask Gosling why he didn't
use the word "temperament" instead of personality. His response was
- and is - that temperament is always invoked as a purely
biological, inherited quality, whereas personality is thought of as
a "higher order phenomenon" that grows out of the interaction of
our inherited temperaments and our experiences. If he used only the
word temperament with animals, he would be dismissing the
possibility that they may have some of the same personality
processes as humans. "I don't want to rule that out," Gosling told
me. "I also think the word personality is as appropriate for
animals as it is for us. Of course, we still have to be suspicious.
People will also rate the personality of a loaf of bread or a car.
A colleague has poked fun at me about that: 'A temperamental car is
difficult to start across time and situations. So why isn't that
personality?' Well, the fundamental difference, of course, is that
with an animal there is an underlying physiology and biology.
Saying my car is temperamental is an analogy. And some people will
rate dogs not only as friendly or fearful but as philosophical.
Now, I do not believe dogs are philosophical, whereas I do believe
in their fearfulness. So we have to be careful where to draw the
line between what's reality and what's analogy."

Dogs, in a way, offer the most obvious proof of the existence of
animal personality. They have long been bound to us and bred by us
precisely for their very particular physical and temperament
traits, and, of course, even among specific breeds there are all
kinds of variation in the personalities of individuals. Indeed,
animals like dogs and cats point up what often appears to be a
paradoxically prodigious "duh factor" behind this otherwise
cutting-edge science. While scientists may tussle endlessly over
the validity of applying the word personality to nonhumans, for
people in the everyday world - especially those who spend any time
around animals - the assertion that they have distinct
personalities seems absurdly obvious.

Not so very long ago, concepts like animal sentience, emotion and
personality were not merely the stuff of anecdotes told by farmers
and pet owners; they were wholly embraced by the scientific
community as well. In the late 19th century, animal emotion and
behavior were integral aspects of the newly emerging science of
human psychology. Charles Darwin devoted much of his time after the
publication of "The Origin of Species" to researching "The
Expression of the Emotions in Man and Animals," published in 1872.
Although that era's cross-species conjecturing and comparing was
often naïve or intuitive, the impulse behind it went on to inform
human psychological study well into the 20th century. Beginning
with the appearance in 1908 of more sober, scientifically sound
works like John Lubbocks's "On the Senses, Instincts, and
Intelligence of Animals With Special Reference to the Insects" or
Edward L. Thorndike's "Animal Intelligence," animal studies figured
prominently in standard human psychology textbooks well into the
1940's. And then, steadily, the animals began to disappear.

At one point in his Austin office on the afternoon I met with him,
Sam Gosling pulled from his shelves the 1935 edition of "A Handbook
of Social Psychology," a standard human psychology textbook of the
time, and showed me the table of contents. More than a quarter of
the textbook's chapters were devoted to studies of animals and
other life forms, titles like "Population Behavior of Bacteria,"
"Insect Societies" or "The Behavior of Mammalian Herds and Packs."
There is even a chapter devoted to "Social Origins and Processes
Among Plants." But in the 1954 edition of a similar work called
"The Handbook of Social Psychology," there is but one chapter
devoted to nonhuman research. Titled "The Social Significance of
Animal Studies," it is essentially a desperate last plea to social
psychologists not to abandon animal studies, arguing at one point
that "social psychology must be dangerously myopic if it restricts
itself to human literature." The warning clearly went unheeded. The
most recent edition of the handbook, from 1998, is devoted entirely
to humans.

The banishment of our fellow beasts from psychological literature
can be blamed by and large on that branch of psychology known as
behaviorism. The field's major proponents, eminent psychologists
like B.F. Skinner, stressed the inherent inscrutability of mental
states and perceptions to anyone but the person experiencing them.
And even though the behaviorists were themselves major proponents
of the use of animals in behavioral research, they sought to rein
in subjective verbal descriptions of the animals' mental states, as
well as the sorts of experiments that relied on such necessarily
vague data. If the human mind was, as Skinner famously referred to
it, "a black box," then surely the minds of animals were even
further beyond our ken.

"The great and enduring contribution of behaviorism," Gosling says,
"is that it introduced the scientific method to the study of
behavior. They said, 'Let's get rid of the fuzzy, sentimental
higher-level descriptions.' And they did. They went to great
efforts to record specific behaviors, things like how many times a
chimpanzee scratched its head or nose. But it's hard to study
higher-order phenomena, things like personality and emotion, in
just those ways. In the end, what you're left with is this long
catalog of meaningless descriptions. If I need to know whether I
can go into that cage or not to clean it, it's not useful to tell
me the chimp scratched its nose 50,000 times in the past year. Just
tell me, Is it aggressive or not?"

In their dogged pursuit of hard science and their strict avoidance
of what Sam Gosling referred to in his first published paper as the
"specter of anthropomorphism," the behaviorists, especially in the
eyes of many who currently study animal behavior, greatly limited
the field of psychology by ultimately outlawing things like
intuition, inference and common sense. Now, however, the pendulum
has begun to swing back in that direction, and it is a shift that
has been impelled, somewhat surprisingly, by hard science.

Advances in fields like genetics and molecular and evolutionary
biology have lent to the study of psychology something that it
really didn't have when behaviorism first came to the fore: a
better understanding of the biological and bioevolutionary
underpinnings of behavior. No longer is the study of animal
behavior rooted in that inherently naïve and anthropocentric desire
to see ourselves in animals or to project upon them our thoughts
and feelings. Animal personality, along with such integral fields
as animal behavior, behavioral ecology and evolutionary biology,
all pivot now around what might be called deep analogies. The more
detailed and specific our knowledge has become of the animals and
of the many differences between them and us, the more clearly we
can see what is analogous about our respective behaviors.

Animal personality, in other words, is now redirecting psychology's
focus in a direction the behaviorists would most appreciate: away
from airy abstractions about personality and down to its very
tangible and widely dispersed roots. It might be thought of as a
kind of biological Buddhism or muscular mythologizing or armed
anthropomorphism: a more disciplined and detailed form of that idle
speculating we have all done in front of the head tilt of a dog or
the sudden skyward shift of a flock of sea gulls or the comings and
goings of ants around their respective mounds.

"Now, those there I can almost guarantee you are females," Jason
Watters, a behavioral ecologist at the University of California,
Davis, told me one afternoon this past autumn. He was pointing to a
cluster of water striders that had climbed up the side wall of one
of the collecting pools in the artificial stream that Watters had
erected at the far western edge of the Davis campus for a six-month
study that he and his lab director, Andy Sih, recently completed on
the role of genetic and environmental factors in the expression of
behavior in water striders: those spindly black, surface-flitting
wraiths whose indent on their tenuous native terrain is never more
than four slightly concave, lunar-module-like landing cups.

Watters personally reared several thousand water striders for the
experiment and would come to know them about as intimately as any
human can an insect. He knew each strider's parents and siblings.
He photographed and marked each of them with paint-on numbers and
then tracked them through more or less every circumstance and
experience in their roughly yearlong lives: what and how they ate,
their responses to new environments or to simulated predator
attacks, their social interactions and mating practices out in the
simulated stream.

"I haven't gathered all the data yet," Watters said, grabbing one
of the clustered striders and confirming his suspicion about its
sex. "But what we do know is that these water striders express
consistent behavioral types. Like in the presence of a predator
some individuals will run and get right out of the water. Others
don't seem concerned whatsoever. Just sit there. Others get out and
then get back in after a little while. So there's a great deal of
variation in what they do. Especially in a mating situation, here
in the stream we've found among the males that there is the
consistently more aggressive guy - so that's his type or his
personality - and then there are these very active, hyperaggressive
males. They're the ones who are always forcing females to have sex
and driving them out of the water and really messing things up for
themselves and everybody. We don't know yet if this is really the
best way to be or what the point of it is. We're working on that.
But I've got to believe there's going to be some circumstances
where it's a good idea to be a really mean, brutish type of guy and
others where it's not."

A similar array of behaviors is now being encountered in other
insects. In her current research at Davis, Judy Stamps, a professor
of biology and animal behavior, has been looking into how early
experience affects habitat selection in drosophila, better known to
you and me as the common fruit fly. Stamps escorted me one
afternoon to one of the biology department's "animal rooms," where
she and her students have been conducting their experiments. The
room was the size of a small walk-in closet, barely large enough to
contain the 11-foot-long metal table before us.

To a tiny fruit fly, however, the strange, artificial fruit-bowl
habitats of upward twisting wire set at either end of the table are
separate universes, the various fruit-shaped planets of which,
Stamps has discovered, fruit flies approach and settle in a number
of ways, some of which depend on early experience and some on their
distinct personalities. Fruit flies born and raised on a plum, for
example, will seek out the next plum to settle upon, as will the
offspring that they raise there: a "no place like home" impulse.
But in the course of their research, Stamps and her students have
also encountered everything from overly shy, timorous fruit flies
to bold trailblazers to downright feisty and ultimately
self-defeating bullies.

"You don't think of drosophila in that way," Stamps told me. "They
can be very territorial, and some of the males are fairly
aggressive. They tussle with each other. When we did our free-range
fly experiments, we marked them individually. We put little colored
paint dots on their thorax. The students loved it. They'd say: 'You
know Blue? He's been attacking everyone this morning. He's on
Banana A, and everyone else is on Banana B. He's the ruler of
Banana A.' Of course, the other thing we've noticed is that
individuals that behave like Blue get into trouble because, you
see, they end up with nobody to mate with."

Another member of Andy Sih's lab, Alison Bell, has done extensive
studies of the three-spined stickleback fish, a tiny
prehistoric-looking fish with armorlike outer lateral plates and
serrated, lancelike spines protruding from the dorsal region. As
well as finding the same spectrum of behaviors in sticklebacks -
from extremely bold and bullying sticklebacks to extremely shy and
timid ones - Bell has found groups of sticklebacks that exhibit a
similar type of behavior: tribelike populations of bold and
aggressive sticklebacks, for example, or of extremely timid ones.
Their collective disposition seems to have been shaped by the
respective environment in which they were raised - whether it was
predator-free or predator-laden - and their physical appearance
reflects their environment as well: the timid sticklebacks having
far heavier armor and longer, more serrated spines.

The questions that scientists are now beginning to address are why
evolution has wielded such a variety of temperaments in animals and
why it hasn't weeded out the clearly deleterious ones: the shyness
and timidity that deprives some members of a group of food or mates
or the overaggression and extreme risk-taking behavior that can
often result in both the disruption of the group's overall
reproductive success and the aggressors' becoming some other
creature's food.

Roland Anderson sees the diversity of temperaments as a
manifestation of that most basic biological imperative of survival,
an array of personality traits being kept in play in a given
species because of the differing, shifting environmental
circumstances that groups may encounter. "What happens," he asked,
"if a big school of herring comes along and eats all the
aggressive, fearless males in a group of smaller fish? Well, there
will still be some of the more passive or shy ones hiding under
that rock that can say: 'Hey, they're all gone now. There's a
nice-looking female over there. I think I'll reproduce with her."'

Andy Sih, like most of his colleagues at Davis, views personality
differences in animals in a Darwinian context. He considers
specific behaviors and preferences from an evolutionary perspective
and tries to determine how various traits affect the long-term
survival of a given species. And in the course of his research on
everything from water striders to salamanders, Sih has become
fairly obsessed with what he calls "stupid behaviors," ones that
don't seem to make any evolutionary sense whatsoever.

"You'd expect animals to be doing smart stuff," Sih told me one
evening over dinner. "The whole tradition in most of evolutionary
ecology has been to emphasize adaptation where organisms do smart
things. But I've been making the case for a while that the most
interesting behaviors are actually the stupidest."

It's typically the males of a given species that seem to figure
most prominently in the stupid-behavior department - the militant,
mayhem-causing water striders and sticklebacks, for example, or
fierce male Western bluebirds, who spend so much time defending
nests or courting females that they completely neglect their own
offspring. But perhaps the most glaring instance of dumb-animal
doings is to be found in the female North American fishing spider.
Studies have shown that a good number of female fishing spiders are
from a very early age highly driven and effective hunters. It is a
trait that serves them well most of their lives, particularly in
lean times, but it wholly backfires during mating season, when
these females can't keep themselves from eating prospective
suitors.

"Now why would anybody, why would any organism do that?" asked Sih.
"If you look at these female spiders just in the context of mating
behavior, you would conclude that they're doing something mighty
stupid here. But their behavioral type is very good for them for
much of their life growing up in a highly competitive world where
food is often scarce. They're so geared up, though, that when
mating season comes around, they really mess up. And experiments
have shown that even if they're given a reasonable amount of food,
they'll still behave this way."

These same hyped-up females have also been shown to be the most
fearless in the face of predators. In simulated attacks, all
fishing spiders retreated underwater. The overaggressive, ravenous
females, however, were always the first to pop back up, giving them
at once the greatest chance of getting available food and, if the
predator was still around, of becoming its meal. Of course, a good
proportion of female fishing spiders are able to make the
distinction between sex and dinner and between finding and becoming
dinner. But for Sih and others, the persistence in certain members
of a species of these extreme behaviors and the inability of some
to modulate that behavior give rise to a more profound question
about the nature of personality types in general and how plastic or
not they actually are, whether in animals or humans.

In animals, it is now becoming evident, there is a certain degree
of evolutionary inertia when it comes to their behavior, wherein
the very behaviors that accord some members of the group a distinct
evolutionary advantage in one set of circumstances can do them in
in the next. They are stuck, to some extent, with their distinct
ways of being. We humans, on the other hand, tend to think of our
personalities as protean, mutable entities that, unlike our
physical selves, we can shape to suit shifting circumstances. Sih
disagrees. He says he thinks that our behaviors, no matter how
complex the human social contexts that help to shape them, are not
nearly as pliant as we believe them to be.

"Behavioral ecologists actually tend to model animals and humans as
both being very flexible, as being capable of changing their
behaviors as necessary to do the right things in all situations,"
he said. But in our own day-to-day experience, he said, we
recognize that humans don't really behave that way. "We all know
that overly bold person," he pointed out. "We have friends like
that. They do things that are just like: Hey, this can get you
killed. What are they doing that for? And there are people that are
shy, and they're missing out on opportunities they could have had."

There is currently a paucity of human studies along these lines,
but a recently published human-personality study of 545 people by
Daniel Nettle of the University of Newcastle in England shows a
strong parallel with some of these recent animal studies. It found
that the more extroverted and outgoing people were, the more sex
partners they tended to have, an evolutionary edge that was
mitigated by the fact that these were the same people who were most
likely to end up in the hospital because of stupid risk-taking
behaviors.

Indeed, however elaborate an argument we humans may have with our
own biology, we are each of us to some extent locked into a
personality type, a consistent way of being without which we would
each be, in a sense, unrecognizable to ourselves or others. The
oft-heard comment "Hey, that's not like you" is a tacit
acknowledgment of your recognizably consistent way of being. If, in
other words, someone were to be entirely flexible and unpredictable
in their behavior, were able to respond with any one of the full
palette of behavioral responses in any given circumstance, they
would be not only, as Andy Sih put it, "scary to be around," but
they would also be someone of whom you could say, they have no
personality.

This set of ideas, Sih told me, suggests new questions that are
rarely posed about humans. "Like why do we even have a
personality?" he asked. "Why do we have a relatively narrow range
of responses as opposed to a full range? Why can't we all be bold
when we need to be and cautious and shy when we need to be? Then
we'd have no identifiable personality, and that would free us all
to become optimal."

For Sih, the answer seems to be that our personality is a
manifestation of a complex interplay between genetic inheritance
and environment and early-life experience. Bold people, for
example, are both naturally disposed to boldness and, further,
choose to be bold, becoming ever better at it, building from an
early age a mountain of abilities and tendencies that become a
personality. It might happen, as well, that an inherently shy
person is induced by an early-life experience to venture away from
his or her natural disposition and cultivate a bold personality.
But whether a person ends up building and climbing a shy or a bold
mountain, it may become increasingly difficult to come back down
and build another one.

"It's not impossible," Sih said, "but it's not going to be easy.
I'll give you another human example. It's always mystified me why
anyone would be a pessimist. It seems to me like optimism has to be
the way to go. But, in fact, there is some recent literature that
shows that pessimists are good at being pessimists. And that when
things go badly, they expected it anyway, and it doesn't hurt them.
And so it's this notion that personality types build because of
these feedback loops."

In human beings, of course, as with other highly social species,
the shaping of personality entails a complex web of influences and
imperatives. It is not merely about the acquisition of food or
mates but involves as well issues of group interaction,
cooperation, deception and so on. It is a dynamic that, in an ever
more complex series of evolutionary feedback loops, at once
impelled the formation of larger and more sophisticated brains and
the more nuanced emotional responses to social interaction -
feelings of embarrassment, guilt, empathy, confidence, etc. - that
such a brain allows.

The attempt to parse that web of entanglements has for decades been
a motivation of fields like psychology, psychiatry and sociology.
What seems so promising about the field of animal personality is
that in the course of allowing us to better understand and more
effectively conserve the animals themselves, it is also affording
scientists new pathways of understanding ourselves and our
behavior, through the kind of experimentation that we are unable to
perform on humans.

"Do thrill seekers thrive in certain speculative business or
military environments?" Sih asked. "I don't know. But I can do
experiments to look at analogous situations in animals, can take
different animals with different personalities and see how they do
in different environments - in a high-predation-risk situation, in
a cooperative situation, during a courtship-mating situation. Along
similar lines, we can test ideas like, Are animals particularly
aggressive when they invade new regions because it is primarily the
bold, aggressive individuals that tend to immigrate to new areas?
How does the personality of the immigrant pool in humans differ
from those who stay behind, and does that difference influence
success - and does this basic view apply to the melting pot of
America?"

Alison Bell has done related experiments with sticklebacks. It has
long been clear to researchers that fish that have lived for many
generations in the proximity of dangerous predators are less bold
and less aggressive than animals that have lived relatively
risk-free. What Bell discovered is that those cautious tendencies
outlast the presence of risk, even by a generation. When she moved
sticklebacks who had always lived in a high-risk environment into a
low-risk environment, she found that not only did they retain their
cautious tendencies, but so did their offspring. Even fish raised
from birth in a low-risk environment behave more fearfully if
raised by a particularly vigilant father from a high-risk
background.

"There's definitely the effect of genetic difference," Bell
explained, "but there's also the effect of what is experienced as
they grow up. Genotype and environment interactions make it
difficult to detect the effects of genes, because you have to take
the environment into account. This is annoying to geneticists." To
scientists like Bell who are studying the interplay of genes and
environment, however, it is of profound interest.

In the coming year, the sequence of the full stickleback genome
will have been assembled, which will open doors into all kinds of
cross-species research on the relationship between genes and
environment. Alison Bell will be looking at such things as
risk-taking behavior in sticklebacks - which may, by extension,
give us insight into the behavior of humans. The same genes and
hormone receptor systems associated with such behaviors have been
conserved across a broad spectrum of species from sticklebacks to
rhesus monkeys to us. John Capitanio has already done a number of
experiments with rhesus monkeys that look into how the manner of
their rearing affects what Capitanio (in a hedge on the loaded
P-word) calls an animal's "biobehavioral organization" - and how,
in turn, that biobehavioral organization affects everything from
gene expression to immune-system function against ailments like
simian AIDS.

What once seemed the hopelessly subjective pursuit of understanding
human behavior and personality is now increasingly being tied down
to and girded by the objective moorings of our own and other
animals' biology. The very names of newly emergent fields like
biological psychiatry, molecular psychiatry and, of course, animal
personality reflect this trend. It is not, as Capitanio points out,
a reductionistic concept but more of a holistic one, one that
allows for an unprecedentedly subtle reading of the integrative
influences - genetic, experiential and environmental - that shape
each individual's personality.

Capitanio is currently writing, with Sam Gosling, the first chapter
on animal personality to be included in "The Handbook of
Personality," a standard reference book of human-personality
psychology. This week, he will be in Palm Springs, Calif.,
presenting a paper on personality in rhesus monkeys as part of an
animal-social psychology symposium led by Gosling at the annual
meeting of the Society for Personality and Social Psychology, the
first symposium of its kind at a human psychology conference. For
Gosling, it is the realization of the very thing he envisioned when
he first started pursuing the possibility of personality in animals
at Berkeley back in the mid-1990's.

"What really got me interested when I started exploring this,"
Gosling told me, "is I noticed that what the animal researchers
were doing in practice was exactly what human researchers were
saying would be the perfect study they could do in a perfect world.
Like you ask a human personality researcher, they might say what
we'd do is take a bunch of individuals, and we'd watch them from
conception till death and record all the major events in their
lives and know who mated with whom and who had a fight with whom.
And if we wanted, we could give them frightening stimuli and so on.
And a lot of my job is saying to those in human psychology: 'Hey,
you should talk to these other guys. What they're doing is really
relevant.' I'm like the middleman."

Looking through some of the animal-personality literature in
Gosling's office that afternoon, I came upon an intriguing paper
titled "Microscopic Brains," published in the March 13, 1964,
edition of the journal Science, in the midst of the great animal
blackout from psychological literature. Written by a professor of
zoology and psychology at the University of Pennsylvania named
Vincent Dethier, the paper is at once a study of insect behavior
and a remarkably prescient argument for a more intuitive,
empathetic and integrative approach to the study of psychology.

"The farther removed an animal is from ourselves," Dethier writes,
"the less sympathetic we are in ascribing to it those components of
behavior that we know in ourselves. There is some fuzzy point of
transition in the phylogenetic scale where our empathizing acquires
an unsavory aura. Yet there is little justification for this
schism. If we subscribe to an idea of a lineal evolution of
behavior, there is no reason for failing to search for adumbrations
of higher behavior in invertebrates."

Dethier concludes on a decidedly haunting note: "Perhaps," he
writes, "these insects are little machines in a deep sleep, but
looking at their rigidly armored bodies, their staring eyes and
their mute performances, one cannot help at times wondering if
there is anyone inside."

We will never know, of course, one way or the other. And yet
somehow, science, of all things, is rendering the empirical answer
to such a question incidental to a more felt and intuitive one.
Perched now, like entranced children, along the banks of their
respective simulated streams, scientists are staring for hours at
the least human of creatures - everything from bullying fruit flies
to ravenous, oversexed water striders and fishing spiders to
perilously fearless hordes of armored stickleback fish - and are
beginning to see in them not just their distinct patterns of
behavior but also something deeply and distinctly recognizable.
Something, well, not altogether inhuman.

Charles Siebert is a contributing writer and the author most
recently of "A Man After His Own Heart: A True Story."