Relentless Evolution

This book is dry in the extreme. To honor that, this review will itself be extremely dry. Just kidding...or am I? You decide. It took me a year to wade though Relentless Evolution and I certainly wouldn't recommend it as a light beach read. The citations along extend for over a hundred pages!

Adaptive Evolution

Thompson opens his tome talking about adaptation. This seems to be as good a place to start as any. Adaptation is certain traits which lead to successful reproduction in a given environment being favored in that environment. This provides a nice entry for him to talk about how whereas once we saw evolution as a long historical process today we can see viruses, insects, bacteria and other organisms with short reproduction times evolve. Indeed, it seems like there's a new strain of the flu to fight off every year.

Natural Selection

This'd be your classic Darwinian process: more individuals with variant A of a trait survive to reproduce than those individuals with variant B or C of said trait. Thompson's examples here include butterflies, cod and, in the human altered environment of hospitals, drug resistant bacteria.

Genes

More butterflies, moths, sticklebacks, mice, flax and even dogs are employed to show how genes - proteins transcribed from DNA - form traits in the animals carrying them.

Genomes

It talking about whole genomes, that is, whole organisms, Thompson's examples stick to sealife and plants. He spends a great deal of time discussing polyploidy, the duplication of genomes. Most multicellular creatures like to think of themselves as diploid, receiving a genome copy from each parent. The exceptions to this are instructive.

Male ants are not diploid; they only get a single copy. Thus all the female offspring of a queen (sisters) carry 75% of the same genetic material whereas any female's offspring will only have half her genes. Colony behavior makes complete sense in this light.

On the other end are plants, which can be successfully tetraploid. This doubling can even be repeated over multiple generations leading to 8, 16 or more copies of the genome in a single organism!

Last of all there is hybridization, where two separate species join their genomes to produce offspring. You know, like Ligers and Tigons.

Genome Coevolution

Here Thompson considers the evolutionary basis of symbiosis. Sadly he does not mention the dangers of picking up spider suits in distant galaxies. He does go into some detail about the human microbiome, however, which is interesting.

Genome Conflict

Microbiota, nuclear-mitochondrial conflict, parasites, etc. all shape an organism's genome. Perhaps the most interesting anecdote here is that of Wolbachia, a bacteria which infects insects and can cause infected individuals to only be able to successfully procreate with other infected individuals, kill off males, and other insidious things.

Adaptive Variation

At some point this book really starts to repeat itself. This is the first chapter in which we encounter the Galapagos finches. Rest assured. It will not be the last. Variation within a species' population can add to the fitness of that population by allowing for quick responses to changing circumstances, i.e. changing your beak size when El Niño comes knocking at your door.

Recombination & Reproduction

Sex! You'd think Thompson couldn't possibly make that subject a bore. And you'd be wrong. Oh, and horizontal gene transfer is probably more important than we realize.

Divergence

Thompson focuses on the variation of moths, specifically those in the genus Greya living in the western United States. Different species have evolved different ranges to prey on the same plants and to prey on different plants in the same geographic ranges. This moth and the flowers in its life will be a recurrent theme in Thompson's discussion of coevolution.

Local Adaptation

Species randomly spread to new areas. Places distinct from their home ranges in any number of ways can exert selective pressure. This is the driving force behind local adaptation.

Coevolutionary Dynamics

Species sometimes evolve TOGETHER. Imagine that.

Geography

Here Thompson appears to repeat a lot of what he said in the chapter on local adaption with different examples. I'm not sure why this chapter is here other than to showcase all these examples. Maybe that's how one gets their bibliography over 100 pages...

Experiments!

Since most evolution science tends to be descriptive, I found Thompson's 13th chapter to be a special treat. Of course, because of the finite nature of the human lifespan, these experiments tend to focus on species that reproduce quickly like bacteria.

Ecological Speciation

Here we find a continuation of the foregoing chapters on local adaption, but focused on when one can declare separate species. Mainly this focuses on whether when they hybridize they can produce viable offspring.

Reticulate Diversification

The discussion of hybrids continues, referring back to our old friend the Greya moth among other examples. Sadly no discussion of the Liger or Tigon was included.

Species Interactions & Radiations

Local adaption plus coevolution expounded upon in copious examples.

Webs

Coevolution as mentioned earlier highlighted binary examples, that is, two species evolving together. Nature is rarely so simple. In most cases there is a whole host of species interacting together in a web.

Perceptions of Evolution

Thompson argues that scientists need to stop using euphemisms and just say evolution. He would know. He's used every single one at some point in this book. Still, I can't agree more! The word "evolution" is something like "Voldemort" when communicating with the general public. The historical conflict between scientific worldviews is, of course, to blame, and I, like Richard Dawkins, believe we need to firmly state which side of that argument we fall on. Say evolution!

-- Coda --

I initially picked up Relentless Evolution because of a review in Science which, as I remember, portrayed it as being somewhat more exciting. Perhaps one will find value in comparing that analysis to the current one.