instinctual

In light of the IF topic "instinct," I went poking around Wikipedia and ISI Web of Knowledge for information on instincts: how exactly they're defined, how they're developed, are they evolutionary, how do they differ from reflexes, etc. etc. etc. Apparently this is all stuff that's been hotly debated by anthropologists and brain-studiers for centuries.

Here's what Wikipedia says:
(From a text published in 1961)
To be considered instinctual a behavior must:

a) be automatic
b) be irresistible
c) occur at some point in development
d) be triggered by some event in the environment
e) occur in every member of the species
f) be unmodifiable
g) govern behavior for which the organism needs no training.

The absence of one or more of these criteria indicates that the behavior is not fully instinctual.

Also according to Wikipedia, the processing for a reflex happens in the spinal cord, whereas the processing for an instinct happens in the brain itself.

Animal instincts include things like hibernation, migration, nest building, and mating. Humans don't really do most of these (well, except mating, but the instinct is modifiable and resistible enough that we don't all go around jumping each other in the street).

So do humans have true instincts? The question's still open.

[ink, Photoshop, and GIMP]