Genome complexity: de novo or orphan genes (Introduction)

by David Turell , Tuesday, April 10, 2018, 14:58 (2420 days ago) @ dhw

QUOTES: "In corals, jellyfish and polyps, orphan genes guide the development of explosive stinging cells, sophisticated structures that launch toxin-filled capsules to stun prey. In the freshwater polyp Hydra, orphans guide the development of feeding tentacles around the organism’s mouth. And the polar cod’s orphan antifreeze gene enables it to survive life in the icy Arctic.”
"Up to a third of genomes have been found have been found to be unique, as this review explains:
Comparative genome analyses indicate that every taxonomic group so far studied contains 10–20% of genes that lack recognizable homologs in other species. Do such ‘orphan’ or ‘taxonomically-restricted’ genes comprise spurious, non-functional ORFs, or does their presence reflect important evolutionary processes? Recent studies in basal metazoans such as Nematostella, Acropora and Hydra have shed light on the function of these genes, and now indicate that they are involved in important species-specific adaptive processes.”

DAVID’s comment: If evolution was a totally natural process, it becomes very difficult to explain natural common descent if 10-20% of genes have no relatives in preceding generations of species. Direction by God fits.

dhw: Speciation involves innovation of some kind, and it seems to me perfectly reasonable to assume that innovations are triggered by the drive for survival and/or improvement, in accordance with the living conditions of the organisms involved. This is illustrated by all the examples. If common descent is true, then of course there will be departures from each new species’ ancestors, and these will in some way involve innovative changes to the structure and function of cells and genes. What is your proposal? The Arctic cod is still a cod, so did your God preprogramme cod anti-freeze 3.8 billion years ago? Or did he see a cod freezing and pop down to give it some brand new genes? But yes, you can say that fits (though one can’t help wondering why he found it necessary to provide the polar cod with anti-freeze when apparently all he wanted to do was produce the brain of Homo sapiens), but whatever he may have done to the cells could also have been done by his providing cells with the autonomous means to do exactly the same thing. As always, the complexity of such an autonomous mechanism offers a powerful argument for design, but I’d be surprised if you thought your God was incapable of doing it.

This post covers the arguments you have put forward on the ant thread, which we can now close.

They are all forceful arguments for specific design. Whether God stepped in or gave the organisms inventive adaptive mechanisms, it doesn't matter. It is all at God's direction.