Evolution is such fun. Just read about Darwin's voyage, the campaign he mounted against the fundamentalist paradigm of the time, the weird and fantastic solutions natural selection creates with simple trial and error, using a code with just four characters. And it reaches so far that there is, in Dan Dennett's words, no need for a skyhook. Nothing supernatural, nothing at all.
But if you follow W.D. Hamliton and R. Dawkins' line of thinking, as I do, you see about all of the biological selection happening not to species, populations or even organisms, but to genes -- then you really need to go down into the cell to look around. And when you do, I'd recommend following an excellent biochemist named Nick Lane; he's one of my top shelf popular science writers. He made something that was perfectly baffling to me just ... incredibly confusing.
I pace myself with Dr. Lane, his books are not easy reading and I've only done two: Power Sex and Suicide (2005) and Life Ascending (2010). He won the Royal Society Prize for Science Books for the latter, putting him in the company of Diamond, Hawking, and Bryson. And Gould.
Power, Sex, and Suicide is about mitochondria, those little captive creatures which live in our cells with their own DNA, all clones from one's mother alone. They make heat and they make little energy pellets called ATP which they ship around the body. They really are essential. So much for being a single living creature, each of our cells has one -- some have thousands of these girls.
It’s believed that bacteria once invaded a cell, or were consumed by one, and they got along so well they're still camping out. Sperm cells use these things for swimming but jettison their tails before penetrating the egg. Why? Because, Lane explains, when different mitochondria meet they fight, and injure each other in the germ cell, so they have "agreed" that the male bits should just stay out and avoid quarrels. Female go, male stay. If there were three genders the solution would be way too weird -- every gender would have to go in some situations yet be prepared to stay in another, like rock, paper, scissors. So most of the animal kingdom and most plants too have just two genders. I just think that's a cool thing to (sort of) know.
Life Ascending takes the same micro approach, and I enjoyed it as much. He takes ten evolutionary inventions in ten chapters, starting with the origin of life. His position on first life is, I think, the dominant one: chemical processes at the pH/heat gradient vents on the ocean floor. Don't worry; he takes you step by step through the process: geochemical mixing in the tiny porous rock, which made a cell-like enclosure, then a reversing Krebs cycle, and finally a proton gradient which allowed accumulation of excess energy. Something like that. At the time I remember feeling like I followed the progression, and I'm still a little proud of myself for it.
Other chapters are on DNA, photosynthesis, the eukaryotic cell, sex, movement, sight, hot blood, consciousness, and death. Each one made clear and relatively simple without (I felt) cutting a lot of corners.
Lane supports the free radical theory of ageing, one of three ageing theories, I'm told, in which all degeneration of body systems result from a single process which can be slowed by (basically) giving the cells a break from processing calories. "I would be amazed," he writes "if we didn't have an answer within the next two decades ... that cures all the diseases of old age at once." Holy cow. He made this same claim in Power, Sex, and Suicide, convincingly enough (to me) that because of Nick Lane I purposefully lost 20 pounds of my body weight -- that's 12%. Hunger, he convinced me, is my friend.
The chapter on movement may have been the least controversial of the batch but the most difficult to follow. Apparently muscle tissue and the parts of plants which track the sun are similar to, and derive from, systems of mitochondrial transport operating within the cytoskeleton -- the inner cell wall. Who knew!!?
You'll work for it -- at least I did. But I found every chapter do-able, and exhilirating to finish. I'm looking forward to the prequel: Oxygen (2002).
Another page-turner, I'm sure.