Criteria of Calling Something Adaptive
If and only if a trait fulfills the following criteria will evolutionary biologists in general declare the trait an adaptation:
- The trait is a variation of an earlier form.
- The trait is heritable through the transmission of genes.
- The trait enhances reproductive success.
Adaptationists too agree with these rules, but their opponents maintain adaptationists are sometimes too eager to take an imaginative leap where the evidence is spotty or ambiguous.
Evolution cannot form perfect organisms for numerous reasons. Foremost is that some elements of an organism's physiology are subject to constraints that environmental pressure cannot alter.
Read more about this topic: Adaptationism
Famous quotes containing the words criteria of, criteria, calling and/or adaptive:
“We should have learnt by now that laws and court decisions can only point the way. They can establish criteria of right and wrong. And they can provide a basis for rooting out the evils of bigotry and racism. But they cannot wipe away centuries of oppression and injustice—however much we might desire it.”
—Hubert H. Humphrey (1911–1978)
“We should have learnt by now that laws and court decisions can only point the way. They can establish criteria of right and wrong. And they can provide a basis for rooting out the evils of bigotry and racism. But they cannot wipe away centuries of oppression and injustice—however much we might desire it.”
—Hubert H. Humphrey (1911–1978)
“‘No, go I must, they’re calling
me.’
‘Who are they?’
Rising he said “Some
day you’ll know. They’re calling to you
too.’ Darkly he rose, and then I slept.”
—Frank O’Hara (1926–1966)
“The shift from the perception of the child as innocent to the perception of the child as competent has greatly increased the demands on contemporary children for maturity, for participating in competitive sports, for early academic achievement, and for protecting themselves against adults who might do them harm. While children might be able to cope with any one of those demands taken singly, taken together they often exceed children’s adaptive capacity.”
—David Elkind (20th century)