Furthermore, if A is preferred when both B and C are available, then A should ‘rationally’ remain the first choice when only A and B are at hand — a principle called the independence of irrelevant alternatives (IIA).
But sometimes animals do not display such logic. For example, honeybees (Apis mellifera) and gray jays (Perisoreus canadensis) have been seen to violate IIA, and so have hummingbirds (Selasphorus rufus).
Researchers have now used a theoretical model to show that, in fact, violations of transitivity can sometimes be the best choice for the given situation, and therefore rational. The key is that the various choices might appear or disappear in the future. Then the decision becomes more complicated than a simple, fixed ranking of preferences. So while these choices look irrational, they aren’t necessarily."
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