Geoscience Reference
In-Depth Information
vidual and social lives, language, tools, and even culture, in which parent birds ac-
tually pass down information to their young.
Nevertheless, if you are skeptical about the term “bird intelligence” and need
examples, here are a few. How about recognized gradations of bird language, in
which birds can tell one another through alarm calls that a possible threat is com-
ing from above (a hawk) or on the ground (a fox)? This was verified with chickens
(
Gallus gallus
), which are often impugned as the dumbest of all birds and thus de-
serving of roasting pans. Not complex enough behavior for you? Okay, how about
when birds inform one another that not only is a human approaching but a specific
individual who harassed them several years before? Or that they then teach this to
their children? This sort of learning, recall, and teaching ability has been documen-
ted in American crows. Other birds that can learn individual human faces include
pigeons, magpies (
Pica pica
), and northern mockingbirds (
Mimus polyglottus
); the
latter can learn to associate specific faces as threats within about thirty seconds.
Still not impressed? How about superb fairy-wrens (
Malurus cyaneus
) giving their
chicks a “password” (a single note) as a cue for feeding, but while the chicks are
still snugly inside their eggs? Researchers who verified this found that the fairy-
wrens had likely evolved this behavior as a defense against feeding the hatchlings
of cuckoo birds.
Given these samples, it should not be such a stunning revelation that birds are
also among the few animals that use and make tools. Nonetheless, when this was
first documented starting in the 1960s, it was an eye-opener for behavioral biolo-
gists. After all, the conventional wisdom at that time was that only primates used
or shaped implements from their environments to accomplish a task. Although bird
tools are oftentimes quite understated as traces (how many people can tell whether
awren used acactus spine topryoutaninsect?), it is still goodtoknowabout these
and add them to their bird-trace checklists.
Tool-using birds include, at a minimum, New Caledonian crows (
Corvus
moneduloides
), woodpecker finches (
Cactospiza pallida
) of the Galapagos Islands,
