Offhand, and without thinking of it much to the 1st Q, I'd probably say spore forming bacteria came first. That's kinda like an egg, right? Probably happened a billion years before we saw reptiles, or birds—all reproducers by means of encapsulated, self sufficient wombs.
Well, Mark let the cat out of the bag in terms of who's likely to be publishing the book Tim and I have been working on since early December, and Dr. "Grace" BG since a month or so ago as Amazing Science Editor—which is going to go down as the best idea to which I've ever capitulated. :) Tim insisted. We've now entered the realm of having too much, possibly. About 400 pages, hundreds and hundreds of references, a huge number form 2013 and even...2014. We get assaulted daily.
...Anyway, this notion or framework in thinking about evolution is something Mark and I have talked about. He mentioned it in the podcast with Dave Asprey linked above, and it is already well ingrained in the narrative of the book (which is my primary responsibility).
Did we evolve and gut bacteria were opportunists or, are we essentially the product of the first on the scene, 3 billion years ago and counting, going through about a half dozen generations of evolution per day, compared with our 30-year-long single generations?
Oh doG, what's happening to my universal view? What about THE BIBLE, written by sheepherders following a handyman with prophetic Messiah delusions—just like about 300 or so others—only with worse writers, such as to be dismissed by the Romans as not politically viable?
Or, maybe it's to the advantage of the 100 trillion gut bacteria who regulate all manner of gut pH, SFCA production, hormonal production and regulation, and are plugged right into the brain with all of it. Maybe they need us to be kinda stupid, for their own survival and ours. Wisdom of crowds? there's 100 trillion of them. after all.
We are the Borg. Resistance is futile. You will be assimilated. We will integrate your technology and make it our own.
Although the gut microbiome influences numerous aspects of organismal fitness, its role in animal evolution and the origin of new species is largely unknown. Here we present evidence that beneficial bacterial communities in the guts of closely related species of the genus Nasonia form species-specific phylosymbiotic assemblages that cause lethality in interspecific hybrids. Bacterial constituents and abundance are irregular in hybrids relative to parental controls, and antibiotic curing of the gut bacteria significantly rescues hybrid survival. Moreover, feeding bacteria to germ-free hybrids reinstates lethality and recapitulates the expression of innate immune genes observed in conventionally reared hybrids. We conclude that in this animal complex, the gut microbiome and host genome represent a coadapted “hologenome” that breaks down during hybridization, promoting hybrid lethality and assisting speciation.
Our science begins with the questions of who we are as animal-microbe chimeras and who we are as an animal species. Traditionally, most of us see the living world through a refined set of filters: the animal genome is stably inherited, subject to natural selection, and determines how new species arise from descent with genetic modification. Yet there is a transformation occurring today in our capacity to understand who we are beyond our nuclear genes. Indeed, the science of the microbiome has emerged in the last decade to massively widen the recognition, if not scope, of a species dependency on microbes. In this specific study, Dr. Robert Brucker and I set out to test if the gut microbiome has been overlooked in the process by which new species arise.
Using a model insect system, we first discovered evidence that the DNA from the gut microbiome can retain information on the ancestry of how animal species are related to each other (termed “phylosymbiosis”), just like the DNA in the nucleus’ genome (termed phylogeny). Second, we showed that the gut microbiome is essential to stopping interbreeding between the species. In a series of hybridization experiments with and without a gut microbiome, the work demonstrated evidence that both the DNA from the nucleus and gut microbiome are essential to the speciation process. A mismatch between the right microbiome and nuclear genome is what underscores why hybrids die between species, thus potentially spurring the origin of species.
This work is different from previous studies because it adds the gut microbiome to a short list of genetic entities that can cause speciation – what Darwin deemed the mystery of mysteries! In addition to the divergence in DNA sequences in the nucleus and mitochondria, the changes in the gut microbiome can promote the evolution of one species into two.
[...] Evolution is defined as a change in DNA that occurs over time, leading to new adaptations and speciation. If one looks at the gut microbiome as a major, if not dominant, component of the DNA of a host animal, then changes in the gut microbiome can quite naturally lead to new adaptations and speciation just like changes in nuclear genes. We adhere to this view and suggest that the gut microbiome must be considered a major portion of the genetics of an animal, in combination with the nuclear genome and organelles – what is now called a hologenome.
Uh, sorry creationists: Evolution in real time.
Lenski has watched E. coli bacteria multiply through 59,000 generations, a span that has allowed him to observe evolution in real time. Since his Long-Term Experimental Evolution Project began in 1988, the bacteria have doubled in size, begun to mutate more quickly, and become more efficient at using the glucose in the solution where they’re grown.
More strikingly, however, he found that one of the 12 bacterial lines he has maintained has developed into what he believes is a new species, able to use a compound in the solution called citrate — a derivative of citric acid, like that found in some fruit — for food.
But I'll tell you what. It's supposedly a free country, so creationists get to be as stupid as they want to be. They get to just open their 2,000-year-old good book, written by sheepherders following a mentally disturbed handyman with a daddy complex.
...Alright, all you smart folks who have to encounter ignorant creationists bringing up "the species problem" ...you have a new link to share.