Well, this is interesting, for sure: “The findings show that this broad class of single-stranded DNA viruses, which infect all three cellular domains of life, have acquired their genetic components through complex evolutionary processes not traceable to a single ancestral event.” Maybe there wasn’t a “single ancestral event” for cells either. Also: The hope is to “resolve the question of how cell-based life came to co-exist with the planet’s staggering array of viruses (dubbed the virome).” One commonly heard hypothesis is that viruses are degraded cells. It will be interesting to hear alternative theses.
Viruses seem to be everywhere, doing a lot of things, with apparent “ingenuity.” Maybe a discovery down the road will be that they cause many changes currently interpreted according to some Darwinian theory (kin selection, costly fitness, what have you … )
Do viruses think? Not in the human sense. As with plants, these communications are signals, not abstractions. But the signals raise an important question: If viruses seek to remain in an organized state, why are they not “alive”? If they are not “alive,” what are they?
How can viruses have altruism if they are not alive? Let’s assume that this is not an argument for panpsychism (You are conscious, sure, but so is your coffee mug.) It seems to be an argument that viruses behave as life forms do.
As described, the authors’ explanation doesn’t follow. The Medusavirus substituting its own DNA for that of the host is no different from the cuckoo substituting its own offspring for another bird’s in a nest. The fact that the strategy works does not necessarily demonstrate a hereditary relationship between the two species.
Giant viruses have only been known from the past few decades. There is still debate about whether viruses are actually life forms. Surely, there will be many game changers to come. Anyone attempting to compile an evolutionary history of giant viruses would be like the person who writes the history of a major league playoff series after the first game. Without the crystal ball.
Maybe in some fields, we need more “stupid” ideas that don’t depend on what “should have” evolved.
Researchers: It has long been believed that all of the genome segments must move together from cell to cell to cause an infection. But the new study shows this is not the case.
The genome isn’t what it used to be.
Delivered by comets. Abstract: We review the salient evidence consistent with or predicted by the Hoyle-Wickramasinghe (H-W) thesis of Cometary (Cosmic) Biology. Much of this physical and biological evidence is multifactorial. One particular focus are the recent studies which date the emergence of the complex retroviruses of vertebrate lines at or just before the Cambrian […]
Which now seem to serve an as-yet-unknown function in the bat. From ScienceDaily: Some 18 million years ago, an ancestor of mouse-eared bats “stole” genetic material from an ancient virus related to Bola. The swiped genetic sequence — a gene called VP35 — has remained largely intact in the bats despite the passage of time, with few […]
From science writer Suzan Mazur, at Oscillations, interviewing Bogdan Dragnea, who studies the physical structure of viruses via spectrosopy: Suzan Mazur: Do you consider viruses live organisms since viruses can recognize their targets, attach, and infect their hosts—most viruses using a tail spike and needle [see following Parent lab image]—and as you’ve noted, they can […]
From ScienceDaily: In 2013, the discovery of two giant viruses unlike anything seen before blurred the line between the viral and cellular world. Pandoraviruses are as big as bacteria, and contain genomes that are more complex than those found in some eukaryotic organisms (1). Their strange amphora shape and enormous, atypical genome (2) led scientists […]