F. Bjorklund is a Professor of Psychology at Florida
Atlantic University, where he has taught graduate and
undergraduate courses in developmental psychology since
1976. He received a B.A. degree in Psychology from the
University of Massachusetts in 1971, an MA degree in
Psychology from the University of Dayton in 1973, and
a Ph.D. degree in Developmental Psychology from the
University of North Carolina at Chapel Hill in 1976.
His current research interests include children's memory
and strategy development, cognitive developmental primatology,
and evolutionary developmental psychology.
has received numerous teaching awards from Florida Atlantic
University, and he is the author of several books, including
the forthcoming The Emergence of Evolutionary Developmental
Psychology with Anthony Pellegrini.
Bjorklund currently serves as Associate Editor of Child
Development, published by the Society for Research in
Child Development, and has served on the editorial boards
of several professional journals and as a contributing
editor to Parents Magazine. He has published over 90
scholarly articles on various topics relating to child
development, focusing primarily on memory development.
links to this scientist's home page and other related infomation
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Chris Rushlau asked:
chimps have imaginations?
a sense, yes. People who work with chimpanzees in captivity
are often amazed at the sort of clever things they see
chimps do. For example, one of the chimps at our sanctuary,
Grub, loves to make paper masks out of strips of cardboard.
After he carefully tears two eyeholes in the paper,
he will then hand the masks to his human caretakers
to don while they chase him around his enclosure playing
tag! But this might not demonstrate imagination, per
se, because it's not entirely clear what Grub is thinking
when he's doing this. (It might only be a sort of ritual
that he's associated with having fun, and something
that his caretakers have encouraged.) Imagination requires
the ability to cognitively combine conceptual elements
that do not normally appear together - such as when
4-year-olds treat a banana like a telephone - and it
isn't clear whether chimpanzees are able to do this
on their own.
have worked with and studied New World monkeys for the
last 10 years. I have 2 questions for you; do capuchin
monkeys actually know it is their reflection in a mirror?
Will a male capuchin always try to win dominance throughout
his entire life? Or does it have the intelligence to
realize that he's not strong or big enough to win the
recognition has been used as a sign of self-awareness.
Monkeys exposed to mirrors certainly look in them and
seem to find them fascinating, but this alone does not
imply self-recognition. To test for self-recognition,
scientists use the "mark test" in which a mark is placed
on an animal's forehead, without them knowing it. Now
when animals look in the mirror, will they realize that
the image they see with the strange mark on the forehead
is them? If they do, they will touch their own foreheads.
If they do not, they will touch the mirror. Human children
beginning about 18-months of age "pass" this test (that
is, touch their foreheads), as do chimpanzees and orangutans,
but at an older age. Most gorillas seem not to understand
that they are looking at themselves in the mirror, and,
to my knowledge, no monkey, even the very bright capuchin,
"pass" this test. So, to come to the point, it is likely
that capuchin monkeys who see themselves in the mirror
to do not know that they are looking at their reflection.
your second question, you, with your 10-years experience
working with capuchins, would actually be in a better
position to answer that than I. Older chimpanzees, after
losing battles with younger and stronger chimpanzees
for dominance, will often "take their place" as a lower
ranking members of the troop. I would think that, in
the wild, capuchins show similar behavior.
Susan Hammer asked:
Do chimps go into estrus? Is the swelling what was observed?
2. Are chimps or the great ape the closest relative
to Homo sapiens?
Susan, Yes, female chimpanzees do go into estrus, and,
you're right, the swelling on their bottoms is the sign
to the males that are in estrus.
Concerning who are humans' closest relatives, it seems
that it is a tie. There are two separate species of
chimpanzees: common chimpanzees (Pan troglodytes) and
bonobos, sometimes called pygmy chimpanzees (Pan paniscus).
All of the chimps that you saw on the TV show were common
chimpanzees. Both species of chimpanzees are equally
related to humans, sharing approximately 98% of their
DNA with us. The other great apes include gorillas,
who share a bit less of their DNA with humans, and orangutans,
who share less DNA still, but more than any monkey.
T. Laurel Marburg asked:
Bjorklund, Hello, I am a Biology and Psychology major
at Virginia Tech with a main aim to study animal behavior,
specifically communication among mountain gorillas.
I have two questions for you. First, how did you acquire
all the chimps you study? And second, have you ever
studied the language development in primates?
I have been fortunate enough to work at the Center for
Orangutan and Chimpanzee Conservation, an ape sanctuary
currently located in Wauchula, Florida. The Center was
originally housed on the grounds of Parrot Jungle in
Miami, and it was there where I first worked with the
chimpanzees and orangutans. Presently, there are six
chimpanzees and two orangutans at the Center. All had
either been raised as pets or in the entertainment industry,
and most came to the center as infants. The Center provides
a relatively spacious and humane environment for these
animals. The Director, Patti Ragan, permits us only
to do research with the apes if she thinks the experience
will serve as an enrichment for them. So you see, this
is not a standard laboratory situation, but one in which
the animals' needs come first. You may want to visit
the Center's web site at: www.prime-apes.org.
And to your second question, I have never done any research
with language development in apes. Two of the chimpanzees
at the Center have been taught some signs and use them
to communicate with their human caretakers, but there
is no "language training" program going on at the Center
as there is in other places, such as Yerkes labs in
you did the experiment with the blackbird as a screwdriver
and the hawk as sandpaper, why didn't you give the chimps
the blackbird and the hawk to see if they used them
as the humans did as sandpaper and screwdriver when
the chimps picked them?
That's a great question! While it would seem as if handing
the objects directly to the apes after seeing the experimenters'
treatments makes sense, there were a number of logistical
problems that we had to face that prevented us from
doing so. Most important of these was the fact that
the taxidermy specimens we used for the 'animate' object
category were relatively fragile, and if you've ever
seen footage of a wild chimp who has just captured a
colobus monkey, you'd see why it would not have been
wise to let the apes handle the objects. Also, we were
concerned that the chimps might learn, after handling
the objects themselves, that there was nothing truly
unique about them; we could therefore only determine
if the experimenters' actions violated the chimpanzees'
expectations by using the visual preference paradigm.
Ankit Vachher asked:
the segment "Chimps Nations", I saw that the chimps
put their hands up in the air and groom. What is the
reason behind this? Why do the chimps groom?
Lets start with your second question first, "why do
chimps groom?" There are at least two reasons for this.
One, is that grooming serves to rid the chimps of parasites,
and it is difficult for them, or anyone, to pick small
bugs off parts of your body that you cannot see, making
grooming by others very practical. But grooming also
plays a social role. Grooming is a way of communicating,
making friends, firming up social relations, and making
up after fights. Chimpanzees are a very social species,
and grooming is one technique in which they relate socially.
As to why they put their hands up in the air, your guess
is as good as mine. Although all chimpanzee groups groom,
only a few put their hands up in the air while they
do so. This suggests that this form of grooming is not
something that is "in the genes," but rather is a tradition
that was developed in some groups but not others and
is passed along to juveniles in the troop. You can think
of this as similar to different forms of greetings among
humans. In Japan, for example, a bow is appropriate,
while in the West we shake hands. Bowing versus hand
shaking reflects differences in culture, and similar
claims have been made for chimpanzees.
the lab environments where your chimps live appropriate
for their needs? Some of the labs such as Alamogordo,
NM, Coulston labs are hellholes for chimps. What can
We certainly believe that no captive environment for
chimpanzees can compare to their natural environment
in the wild. Because the species is best adapted to
the ecological and social conditions under which it
evolved, highly artificial environments, such as laboratories
or poor zoological housing, can lead to a variety of
heartrending abnormal behaviors. Fortunately, most zoos,
and even today's labs, recognize the psychological complexity
of chimpanzees, and are committed to making sure that
their lives are as enriching as possible under the unavoidable
circumstances of captivity. Most modern facilities,
for instance, house chimpanzees together rather than
alone, and provide their charges with materials and
artifacts, structural supports, and vegetation - things
that are critical for apes' contentedness. At the Center
for Orangutan and Chimpanzee Conservation, our first
priority is the psychological and physical wellbeing
of our animals - research is only our secondary concern.
After all, psychological testing on impoverished animals
can lead to findings that do not necessarily reflect
the species in general. For more information on chimpanzee
sanctuaries in the US, or how you can help apes in need,
visit our web site at www.prime-apes.org.