can apes ape?and what do they know about the mind?

dr fenja zieglerc82 sad • lecture 3

unique to humans?

• children display a very early understanding of others’ psychological states

• what about our closest relatives?

apes... good apers?

• will the chimp become more human?

• before age 2: .... superior at all tests (apart from imitation)

• after age 2: reversal in test performance (language?)

Gua & Donald Kellogg

here’s looking at.......what you’re looking at

• why the eyes? why not mouth...?

• 6 months: can track if head shifted

• 12 months: track eyes but only if in own field of vision

• 18 months: even turn around to look behind

Butterworth & Jarrett, 1991

what’s good about tracking gaze?

• social referencing (Source et al. 1985)

• Language development (Baldwin, 1994)

• communication (Robinson & Mitchell, 1992)

can chimps follow gaze?

• chimp looks to spot behind her

• chimp tries to look behind screen

• target cannot be what I cannot see

Povinelli & Eddy (1996)

i like (don’t like) what you’re looking at

adults’ gaze followingLobmaier et al. 2006

• so, we’re good at gaze following...

• ... but ...biased by presence of objects

are we really special?• are chimps

capable of empathy?

• Premack and Woodruff (1978): Does the chimpanzee have a theory of mind?

• do you need empathy to give the right answer?

good cop...bad cop...understanding deception

• good cop gives, bad cop does not... where do you point? (Woodruff and Premack, 1979)

• after 50 trials

• search where the informed person points

• chimps distinguish between bucket/ no bucket Povinelli et

al.

who to ask?• gets around training

study

• who would you ask for food?

• who has food

• who has knowledge of food

• beg if face visible

• no special importance to eyes

non-verbal fb taskCall and Tomasello, 1999

so, do chimps have a ToM?

• reports of tactical deception in the wild (cover that chimphood!)

• failure to solve tasks in lab

• negative evidence

• difference?

• cooperation vs competition

so, do chimps have a ToM?

• reports of tactical deception in the wild (cover that chimphood!)

• failure to solve tasks in lab

• negative evidence

• difference?

• cooperation vs competition

successful behaviour = intention

• unsuccessful attempts and accidents:

• respond to goal or behaviour

• chimps imitate rationally

• chimps understand goals, intentions

altruistic helping

out of reach

out of reach

physical obstacle

wrong result

wrong means

altruistic helpingWarneken & Tomasello, 2006

• children and chimps both willing to help

• no reward

• differ in ability to interpret others’ need for help?

chimps know what others know....and what they believe?

• competitive game

• take turns to choose from 3 containers with 1/2 pieces of food

• understand ignorance but not false belief

has seen one but not the

other hiddenhas made one

choice

has been misled about the

location of the food

can you predict the choice?

select hidden more often if 2nd

brainy birds• dealing with

thieves

• strategies to prevent theft

• only those who had thieved understood about thieving others

• Clayton et al.

social dog... rational ape

Bräuer et al. 2006

nature’s psychologists• social animals have to

become nature’s psychologists

• must come up with way of doing psychology

• introspection, modelling, reasoning by analogy

• elements of social cognition seem to have evolved separately

• animals have ToM ... in some sense

• Bayliss, A. P., Frischen, A., Fenske, M. J., & Tipper, S. P. (2007). Cognition, 104, 644-653.

• Call, J. & Tomasello, M. (2008). Trends in Cognitive Sciences, 12(5), 187-192 (review article)

• Kaminski, J., Call, J. & Tomasello, M. (2008). Cognition, 109 (2), 224-234.

• Kellogg, W. & Kellogg, L. (1933) The ape and the child. New York: McGraw-Hill

• Povinelli, D.J. and Vonk. J. (2003) Trends in Cognitive Sciences, 7.4, 157–160.

• Tomasello, M., Call, J. and Hare, B. (2003) Trends in Cognitive Sciences, 7- 153-156.

• Warneken, F. & Tomasello, M. (2006) Science, 311, 1301-1303

selected key references