Re: What are the definitions of structural, functional & behavioral adaptations?

Variations prevail in nature in all forms of life.
These variations are the raw material for natural selection.
Only animals that are best suited (adapted) survive and reproduce and 
leave young-ones behind....evolve.

  As you have mentioned adaptations can be grouped into those three 
categories (structural, functional and behavioural). But these groupings 
are arbitrary and are interconnected. For example, honey bees evolved 
structures (wings) for a specific function (flying)and behaviour (to fly 
towards flowers).

	Aves are well adapted for their aerial mode of life.
The forearms of birds evolved into structures (wings) that are well
adapted for their new mode of life. As the "hands" were "tied" in wings, 
birds evolved a long flexible neck and a beak to functionally replace 
the "helping hands" in feeding.	New structures are evolved to 
suit a 'new function' (a new mode of life).

	Instinct and learning are good examples of behavioural adaptation.
	Instinct equips an animal with a series of adaptive responses 
which appear 'tailor made' even at their first performance. For example,
Digger wasps have a life span of few weeks. Within the short span of life, 
a female digger wasp after emerging from her underground pupa has to mate 
with a male wasp and dig out a hole, construct cell within it, hunt & kill 
a prey such as caterpillar, drag the prey into the hole it dug, lay eggs 
over it (caterpillars form the food for the newly hatched young ones) and 
finally seal the hole. All these can not be learned and perfected within 
their short span of life.

All these behaviour are inherited in the digger wasp species and are 
readily available as a "ready made" behaviour. Hence 'instinctive' 
behaviour is called as 'species memory'.Instinctive behaviour is a good 
example of adaptive behaviour.