<p>@timmychoo</p>
<p>maybe you are the one who fell in the trap here.
It’s definitely not adaptive capacity so that leaves us with instinctive behaviour & fortuitous circumstance. Wenner went on to
say that birds do not migrate, the strong wind just forces them
to go in that direction. There is nothing
to do with instinct. The wind has caused the birds to migrate. And wenner believed that birds do not want to migrate, there is
no intent. </p>
<p>Fortuitous: Happening by chance; coming or occuring unexpectedly, or without any known cause; chance; as, the fortuitous concourse of atoms.
Happening independently of human will or means of foresight; resulting from unavoidable physical causes.</p>
<p>The circumstances (wind) made the butterflys migrate.</p>