It’s probably not anywhere near as simple and certain as Catherine Jessus is making out. Viruses don’t likely do enough to create placentas. But the main point is, this definitely isn’t yer old biology teacher’s Split-the-Desk Rant for Darwin!!! Stay tuned.
Researchers: “Cooperation is ubiquitous in bacterial populations. Bacteria produce and share public goods, providing indiscriminate benefits to their neighbors at cost to themselves.” It makes sense but it isn’t yer old biology teacher’s evolution.
And here we thought nature was “red in tooth and claw.” From the paper: “We find that positive interactions, often described to be rare, occur commonly and primarily as parasitisms between strains that differ in their carbon consumption profiles.”
Question: If the last common ancestor of the bacterium had a flagellum, what do we really know about the evolution of the flagellum? Isn’t that a bit like finding a stone laptop in a Neanderthal cave? That said, it’s nice to see horizontal gene transfer getting proper recognition.
Researchers: Overall, we showed that LGT is a widespread phenomenon in grasses that has moved functional genes across the grass family into domesticated and wild species alike. Successful LGTs appear to increase with both opportunity and compatibility.
At Quanta: “Davis’ team estimated that at least 1.2% of the plant’s genes came from other species, particularly its hosts, past and present. That might not sound impressive, but this kind of horizontal gene transfer is considered exceptionally rare outside of bacteria. So even a single percent of genes arising this way raises eyebrows.” Researchers are still trying to figure out why the parasitic plant has such a huge genome. Commendably, they are not claiming it’s all junk.
We heard just recently about horizontal gene transfer between herring and smelt. Will we be hearing next about horizontal gene transfer involving mammals via airborne DNA? Don’t rule it out.
We don’t know that HGT is “extremely rare” in vertebrates. We know that it was unexpected so no one was looking for it. We also know that it is extremely inconvenient for a discipline that invested so heavily in natural selection acting on random mutations (Darwinism).
Marshall favors horizontal gene transfer as a key method of early development because ancestor–descendant evolution is a “very slow” (42:25) evolutionary process. HGT among multiple independent lineages, by contrast, allows a “vast exchange of information,” thus sharing innovations and leading to faster development. Okay. And in the midst of all that, Dawkins’s Selfish Gene got lost in a crowd somewhere and was never heard from again.
One senses that the reconstruction will be subject to considerable revision. It’s not entirely clear what “ancestry” means in a world of rampant horizontal gene transfer.
It’s not yet clear why there are fewer types of microbes in urban people’ guts or why they favor horizontal gene transfer more often. But note: At one time, the researchers would be trying to explain it all in terms of Darwinism. That alone shows how much has changed without people really noticing.
Trust our stalwart physics color commentator Rob Sheldon to draw the logical conclusion about horizontal gene transfer between plants and insects: If plants and insects can exchange genes (and who knows what else can?), what are we to make of dogmatic claims about universal common descent?
So what becomes of all the Darwinian casuistry around “fitness” and “costly fitness” if things can happen so simply as this? The article emphasizes the benefits of studying “evolution.” Indeed, but that can’t mean fronting Darwinism 101 any more.
Researchers: This union of two different genomes, called allopolyploidization, is very interesting in evolutionary terms, as it leads to the formation of new plant species and is widespread in many plant groups. Many important crops, such as bread and durum wheat, oats, cotton, canola, coffee, and tobacco have such combined genomes from at least two crossed species.
Evolution News and Science Today describes the idea as “little more than a hunch” but one worth pursuing. It involves endosymbiosis and horizontal gene transfer. Its a start towards a reasonable explanation and way better than classic Darwinism.