Donald Griffin. Animal Minds. U. of Chicago Press, paperback edition 1994.
Chapter 2. Finding Food
1. Why does Griffin think feeding behavior is a good place to look for
versatility in animal behavior?
2. What does Griffin mean by passive prey and by active prey? Why does
he divide the chapter into feeding on passive prey and feeding on active
prey?
3. Formulate Pyke's rules that account for the foraging behavior of
bumblebees (Bombus appositus). How versatile is their foraging behavior?
Does it pose an obstacle to a behaviorist explanation?
4. Why is it difficult to study the feeding behavior of most insect
species? What makes it easier to study the feeding behavior of birds?
5. Describe the feeding behaviors of the pied wagtail (Motacilla
alba yarrellii) and the yellow wagtail (M. Flava flavissima)
along the banks of the Isis River in Oxford (during Spring in the mid-seventies).
Why does Griffin consider this behavior flexible enough to suggest that
simple thinking would be helpful, and therefore adaptive, for these birds?
6. Summarize the feeding behaviors of the redwinged blackbird (Agelaius
phoeniceus) and the yellowheaded blackbird (Xanthocephalus eanthocephalus)
in the marshes of northwestern U.S. and western Canada. Why does Griffin
consider this behavior flexible enough to suggest that simple thinking
would be helpful, and therefore adaptive, for these birds? How plausible
is Griffin's suggestion (hypothesis) that male display behavior may be
communicating such a thought as "Lots of insects here!" to females looking
for a nesting site? Is his suggestion equally plausible or equally implausible
for both redwinged and yellowheaded male display behavior? How does Griffin
think that ethologists could test his suggestion or hypothesis?
7. Is Griffin's statement that "Female blackbirds may be looking for
signs of future food sources as they decide where to settle and build their
nests" objectionably anthropomorphic?
8. How plausible is Griffin's suggestion or hypothesis that blackbird
parents, as they go about feeding their nestlings, may have such thoughts
as "Those youngsters need food" or "That dragonfly will stop its squawking
for a while"? How could one test such hypotheses?
9. Griffin relates that oystercatchers on the coast of Cumbria have
two different ways of opening mussel shells, one when the mussels are fully
exposed (their shells are then tightly closed), and the other when the
mussels are covered by shallow water (their shells are often partly open
then). Although these two methods originally appeared to be an adaptive
adjustment to circumstances and opportunity, it turned out that each individual
oystercatcher specializes in one or the other technique which it learned
from its parents. What is the relevance of this information to Griffin's
project?
10. Griffin relates the versatile feeding habits of the Darwin's finches,
noting that "individual finches employ a wide variety of food-gathering
techniques according to the circumstances, although no one species exhibits
the full range of feeding specializations displayed by the Darwin's finches
as a group." He then speculates on the origin of the special habit of "vampire
finches" who feed on the blood of boobies, likening their hypothesized
pleasant surprise to the unpleasant surprise experienced by Tolman's rats.
What is Griffin's point? Why does he pine for experimental ways to test
hypotheses about hypothesized mental experiences?
11. Why does Griffin think that both natural selection and learning
must exert a strong influence on food-searching behavior. What is a (food-)searching
image? How versatile are birds in acquiring novel searching images via
learning? What does Griffin think this versatility shows about animal minds?
12. Summarize the experimental work of Krebs et al. (using hoppies,
pingies, milkies, & barkies) on great tits (Parus major) to
test mathematical theories about optimal foraging behavior. What's the
difference between social facilitation and observational learning
(true imitation)? How versatile was the foraging behavior of these
birds? Did Krebs et al. establish observational learning or only
social facilitation? Does the experimental work of Sherry & Galef on
milk-bottle-opening behavior of captive chickadees (Parus atricapillus)
throw cold water on the observational-learning claim? Is social facilitation
the more parsimonious explanation? Does Griffin capitulate too readily
when he declares that the novel foraging behavior exhibited by Sherry &
Galef's chickadees "is probably typical of innovation by animals; they
learn that applying familiar motor patterns to new objects or in novel
situations achieves a desired result or avoids an unpleasant one"? How
could scientists detect conscious imitation? Griffin suggests that they
might detect it by eavesdropping on animal communications. How reasonable
is his suggestion?
13. Summarize the shell-collecting-and-dropping behavior of herring
gulls on the shores of Cape Cod as observed by B. Beck. Similarly, summarize
the whelk-collecting-and-dropping behavior of the population of crows near
the coast of British Columbia observed by R. Zach. How much versatility
did these birds show? How much support does it give to Griffin's project?
14. Do wild squirrels locate stored food by means of memory? If not,
how? What about captive squirrels? Why does Griffin say that the observations
made by Sherry, Krebs, & Cowie in their experiments on the caching
behavior of marsh tits under natural conditions suggest -- but do not rigorously
prove -- that these birds were recovering seeds with considerable efficiency?
Why does Griffin think that the laboratory experiments by these same ethologists
on marsh tits rigorously demonstrate that these birds remember the locations
of stored seeds and recover them via memory? What is the significance of
the one-eye-covered dimension of these experiments?
15. Summarize the results of the caching-behavior experiments of Balda
et al. with Clark's nutcrackers. What do they show about memory? About
versatility?
16. Griffin notes that when "it is important for birds and other animals to remember a large number of details, they are often able to do so" and asks whether they think consciously about the task or whether they are "thoughtless memory machines." What Does Griffin mean by a thoughtless memory machine? Would Descartes have considered birds like Clark's nutcracker to be thoughtless memory machines? How do you yourself evaluate the empirical evidence presented in this chapter?