Do apes and children know what they have seen? (results (significant…
Do apes and children know what they have seen?
seeing and knowing in chimps orangutans and human children
whether apes and 2.5-year-old children have access to information about their
own visual perception, and whether they can use this information flexibly to maximize their attainment of rewards.
whether subjects saw the
baiting of the tubes(the screen)
whether the tubes were presented to subjects for
their choice immediately following baiting or instead after
a short delay
seen or unseen
open or closed
how often subjects correctly
chose the baited tube
how often and in what circumstances subjects spontaneously looked into one or more of the tubes before
whether subjects looked when it was appropriate to do so
the search strategies subjects used.
fixed or not?
Looking consisted of
bending the head or body down and gazing into any of the
Choosing consisted of touching one of the
two tubes and it was unequivocal.
significant effects of baiting
significant differences between the two types of delay for the unseen condition but not for the seen condition
Subjects looked more often when E did not
show the food’s location (unseen condition) and when he
delayed the subject’s choice (delayed condition)
Subjects used the efficient search strategy significantly more often than either the insufficient (t=8.91, df=5, P<0.001) or the excessive
(t=5.93, df=5, P<0.01) search strategy
Subjects were more likely to terminate their
search after they encountered a tube with visible food
compared to either a closed (t=4.80, df=5, P<0.01) or an
empty tube (t=4.25, df=5, P<0.01).
If subjects found two closed tubes, they usually selected the last
one they had inspected. In contrast, if they found a closed
tube and then an empty tube, they significantly chose the
first one that they had inspected
Moreover, if they found an empty tube and then a closed
one, they chose the last one they had inspected.
a greater percentage of excessive looks (although still systematic and exhaustive) than
in the previous study
They selected a container if it had food inside, avoided it if it was
empty, and selected it half of the time if it was closed.
The way they gathered information was systematic and exhaustive.
gathering information upon finding the food, but continued gathering information otherwise.
They gathered information about the
food’s location when they did not possess this information
same or not？
subjects numbers are not that sufficient
measurements can be misleading
subjects did not have any metacognitive knowledge at all
but instead learned associations that allowed them to
make the correct choices.
subjects knew not what they knew but instead what they
the costs of checking are low and the
benefits are potentially high