On the Intellectual Abilities of Chickens February 20, 2007Posted by Johan in Off Topic, Sensation and Perception.
Retrospectacle has a post up on yet another in a long line of bizarre PETA ads. The general oddness of the ad aside, it makes the claim that
the cognitive abilities of a chicken rival that of cats, dogs, and even young humans
I’d be the first to admit that it’s difficult to argue over something which isn’t well defined – maybe by your definition, laying eggs and having feathers counts as showing high cognitive function, and frankly, in the absence of a commonly accepted definition of intelligence even in academia, I couldn’t really say much about it.
However, a good old paper by Hess suggests that perhaps, we should think twice before signing chickens up for public education. The picture you’re seeing above can’t really be from the original study, as it was carried out in 1956, so I imagine it’s from some replication. The chicken is wearing goggles which shift the its vision slightly to one side. The chicken’s ability to adjust to this change was measured rather cleverly by having the chicken peck for grain placed on clay, which ensured that each peck left a tidy mark to measure performance by.
This experiment, or a variant of it, is an old favorite in Psychology practicals. Basically, you make a human subject wear these goggles for some time, and test their performancy by having them point at a target with a ballistic movement. The interesting finding is that while performance is initially horrid, it improves quite rapidly as the subject practices. If you next remove the goggles and have the subject do yet another trial, performance is once again impaired, but in the opposite direction. So it would seem that we learn rather quickly to adjust our aim for the distortion that the goggles introduce.
Hess (1956) reported that this was not the case with chickens. Regardless of the number of trials, they never got any closer to the grain. As this was the 1950′s, long before Ethics committees, Hess was able to make this point very clearly, by reporting that two chickens had in fact died of starvation while wearing the goggles, despite having grains scattered around them.
So as long as we agree that the ability to learn is a crucial aspect of intelligence, the score appears to be humans 1 – chickens 0.
Hess, E.H. (1956). Space Perception in the Chick. Scientific American, 195, 71.