Natuurlijk is het duidelijk dat de overeenkomst tussen aap en mens het
grootst is ten opzichte van alle andere dieren, en dat we dus ook met heen de
meeste gemeenschappelijke eigenschappen en capaciteiten hebben. Maar aan de
grens die daartussen gelegd is, wordt nog voortdurend getornd.
Zo wordt er wel gezegd dat het geheugen de belangrijkste
deelfunctie van de hersenen is - en dus moet de mens, met zijn superieure brein,
er wel beter in zijn dan apen:
CNN.com, 04-12-2007 (origineel hier
)
5-year-old chimp beats college kids in computer game
The chimps were faster than humans in some tests
The chimps and humans both had an 80 percent success rate on one test
One chimp kept this score while humans dropped to 40 percent in a new test
Think you're smarter than a fifth-grader? How about a 5-year-old chimp? Japanese
researchers pitted young chimps against human adults in tests of short-term
memory, and overall, the chimps won.
That challenges the belief of many people, including many
scientists, that "humans are superior to chimpanzees in all cognitive functions,"
said researcher Tetsuro Matsuzawa of Kyoto University.
"No one can imagine that chimpanzees -- young chimpanzees at
the age of 5 -- have a better performance in a memory task than humans," he said
in a statement.
Matsuzawa, a pioneer in studying the mental abilities of
chimps, said even he was surprised. He and colleague Sana Inoue report the
results in Tuesday's issue of the journal Current Biology.
One memory test included three 5-year-old chimps who'd been taught the order of
Arabic numerals 1 through 9, and a dozen human volunteers. Watch as the chimps
out-perform the humans »
They saw nine numbers displayed on a computer screen. When
they touched the first number, the other eight turned into white squares. The
test was to touch all these squares in the order of the numbers that used to be
there.
Results showed that the chimps, while no more accurate than
the people, could do this faster.
One chimp, Ayumu, did the best. Researchers included him and
nine college students in a second test.
This time, five numbers flashed on the screen only briefly
before they were replaced by white squares. The challenge, again, was to touch
these squares in the proper sequence.
When the numbers were displayed for about seven-tenths of a
second, Ayumu and the college students were both able to do this correctly about
80 percent of the time.
But when the numbers were displayed for just four-tenths or
two-tenths of a second, the chimp was the champ. The briefer of those times is
too short to allow a look around the screen, and in those tests Ayumu still
scored about 80 percent, while humans plunged to 40 percent.
That indicates Ayumu was better at taking in the whole
pattern of numbers at a glance, the researchers wrote.
"It's amazing what this chimpanzee is able to do," said
Elizabeth Lonsdorf, director of the Lester E. Fisher Center for the Study and
Conservation of Apes at the Lincoln Park Zoo in Chicago. The center studies the
mental abilities of apes, but Lonsdorf didn't participate in the new study.
She admired Ayumu's performance when the numbers flashed only
briefly on the screen.
"I just watched the video of that and I can tell you right
now, there's no way I can do it," she said. "It's unbelievable. I can't even get
the first two (squares)."
What's going on here? Even with six months of training, three
students failed to catch up to the three young chimps, Matsuzawa said in an
e-mail.
He thinks two factors gave his chimps the edge. For one thing,
he believes human ancestors gave up much of this skill over evolutionary time to
make room in the brain for gaining language abilities.
The other factor is the youth of Ayumu and his peers. The
memory for images that's needed for the tests resembles a skill found in
children, but which dissipates with age. In fact, the young chimps performed
better than older chimps in the new study. (Ayumu's mom did even worse than the
college students).
So the next logical step, Lonsdorf said, is to fix up Ayumu
with some real competition on these tests: little kids.
Red.: Op de originele pagina zijn filmpjes te zien van de
experimenten, die niets aan de verbeelding overlaten: het experiment lijkt sterk
op oude bordspel Memory, waarvan het opvallende is het opvallende is dat jonge
kinderen er beter zijn in dan ouderen - en apen zijn kennelijk nog beter.
Nog een zaak die over de grens kan worden geschoven:
Uit:
De Volkskrant, 05-12-2009, ANP.
Apen herkennen vriendjes op foto's
Kapucijnapen kunnen apen die zij kennen, herkennen op foto's. De apen merken
verschillen in gezichten op en onthouden de kenmerken van de apen die zij
kennen. Ook blijken de apen in staat om de tweedimensionale beelden te koppelen
aan de werkelijkheid. Dat blijkt uit een studie van de Nederlandse primatoloog
Frans de Waal die komende week wordt gepubliceerd in het wetenschappelijke
tijdschrift PNAS.
Voor het onderzoek kregen de apen vier foto's van andere apen
te zien. Telkens was er sprake van een combinatie van drie onbekende apen en een
bekende aap of andersom. De kapucijnapen bleken telkens de vreemde eend in de
bijt te selecteren. Dat lukte bij kleurenfoto's en in zwart-wit. ...
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