The Evolution that Didn't Happen

We most often talk of the evolution that occurred.  Yet, some evolutionary steps that could have happened never did and never will. This is a story of one example.

Evolution that doesn’t happen.  I thought of this years ago, but never had a really good example.  Thanks to the BBC series Blue Planet II – Coasts, we see the story of a bachelor sea lion that  discovers a way to trap yellowfin tuna.  Normally, any sea lion could never catch the very speedy tuna. But our bachelor thought up his method to herd the tuna into the dead end of a very shallow coastal region in the Galapagos.   When it first tried, the tuna escaped though the sea lion herded them into the shallows successfully. The problem? He could herd and close the trap at the same time.  Then he recruited some “friends” and they worked together to trap the tuna with one of them closing of the escape route.  Each enjoyed their own 60 kilo tuna – big meal-deal.  The creator of this trapping tuna scheme is no doubt a sea lion genius in the world of sea lions.

Where’s the evolution?  As mentioned, these big boys were bachelors and would not be allowed to mate with a female unless they could challenge the harem master.  But the dominant male is a big fellow, a brute probably not easily beaten in combat.  Since the the tuna trapping genius was a bit smaller, he would probably never challenge for the pod/pack harem.  So, the genius of his genes is lost forever, and the evolution that could happen, never will. 

Thus, evolution toward intelligence, which could occur with a different mating system, will not happen for sea lions - and most other species having local dominant males possessing all the females.