Panspermia? a cause of the octopus? (Introduction)

by David Turell , Tuesday, April 24, 2018, 18:04 (2384 days ago) @ David Turell

We've discussed panspermia before. The theory simply removes the problen of the origin of life on Earth to its origin elsewhere in the universe. The long article gives reasons for considering it seriously, but the most interesting discussion to me is the origin of the octopus section with its conclusions:

https://cosmosmagazine.com/biology/viruses-et-and-the-octopus-from-space-the-return-of-...

"Cephalopods (the group comprising squid, cuttlefish, nautilus and octopus) have a somewhat confusing evolutionary tree, first appearing in the late Cambrian period and seemingly descending from an ancestral primitive nautiloid.

"Of these, the octopus is the most striking, with features, such as a complex nervous system, sophisticated eyes and a capacity for camouflage, that appear quite suddenly in its evolution. The genes necessary for this transformation, the authors suggest, are not present in its ancestry. Thus, they hold that “it is plausible then to suggest they seem to be borrowed from a far distant ‘future’ in terms of terrestrial evolution, or more realistically from the cosmos at large.”

"Interestingly, the octopus has some real and pervasive biochemical differences from the nautilus, presumably the closest living relative of the former’s ancestor. In particular, there is evidence of extensive changes in the RNA, and thus proteins, found in the neural structures of cephalopods.

"These changes have been evolutionarily preserved and are not found to this extent elsewhere in nature, not even in the nautilus. This indicates that a qualitative evolutionary transformation occurred relatively recently and abruptly in behaviourally complex cephalopods. The sheer scale of these changes leads the authors to conclude that it cannot be explained by normal neo-Darwinian processes. Or even Lamarckian processes. And they may have a point.

"But here things get weird. “One plausible explanation, in our view, is that the new genes are likely new extraterrestrial imports to Earth – most plausibly as an already coherent group of functioning genes within (say) cryopreserved and matrix protected fertilised octopus eggs,” write the authors. This would “be a parsimonious cosmic explanation for the octopus' sudden emergence on Earth [about] 270 million years ago.'”

Comment: this reasoning leads to Darwin's discomfort about the Cambrian Explosion. It is too sudden and without the required complex precursors to be explained by any form of gradual evolution. It is best explained as a saltation and I would choose as evidence for a planning mind, God.