More about how evolution works: more on patterns (Evolution)

by David Turell , Monday, March 12, 2018, 13:57 (2446 days ago) @ David Turell

Another take on the Hawaiian spiders that hopped island to island and developed the same coloration each time:

https://cosmosmagazine.com/biology/colonising-spiders-evolve-the-same-three-forms-every...

"Remarkably, Gillespie and her international team, using a mixture of genetic analysis and software modelling, have discovered that the stick spiders constantly re-evolve these same three forms, known as ecomorphs, in a rare example of repeated and predictable convergent evolution.

***

"As, say, a dark species moved to a newer island, it would quickly evolve into three new species, each displaying one of the three ecomorphs. As other Ariamnes species arrived they too would evolve into the three ecomorphs, leaving a pattern of bewildering relations between them. Species that look the same may well be distantly related, while species exhibiting different forms might be close evolutionary kin.

"Importantly, these three forms remain constant.

“'They don't evolve to be orange or striped. There isn't any additional diversification,” says Gillespie.

"This is incredibly rare, only occurring in a lizard species from the Caribbean and, interestingly, another spider species from Hawaii.

"The researchers think a unique set of circumstances bring about this evolutionary déjà vu – a lack of diversity in predators, a limited set of genetics with a possible preprogramed DNA switch to facilitate the emergence of the three ecomorphs, a free-living lifestyle, and an environment that rewards only certain types of camouflage, all seem to contribute. (my bold)

"While the exact reasons remain unclear, Gillespie and her team hope that further research into the similarities within this select group of organisms that evolve the same forms over and again will “provide insight into what elements of evolution are predictable, and under which circumstances we expect evolution to be predictable and under which we do not'”.

Comment: Note the bold. Could pre-programming be the key? I've suggested this as God's way of managing evolution.