Friday, June 03, 2011
Life Ascending: The Ten Great Inventions of Evolution
This is a dense book. It's science written for non-scientists, but it's still very technical. I fell asleep a couple of times, not because it was boring, but because I had to think too much about each sentence. In some ways, it was a terrible book to read on vacation. In others, it was perfect.
Each chapter tells how one feature probably evolved. The features are: the origin of life, DNA, photosynthesis, the complex cell (eukaryotes), sex, movement, sight, hot blood, consciousness, and death. Through these highlights, the author pretty much tells the progression of evolution from the origin of life to humans. There's some of the requisite defense against the dark arts (e.g., arguments that the eye is too complex to have evolved), but for the most part it's a great review of current thinking on each topic. We don't know for sure about any of them, but there are some good and interesting ideas floating around.
One thing I'm proud about: During my time in the Galapagos, someone posed the question of how the Cambrian explosion came about. This was the period about 540 million years ago when suddenly wild and crazy animals began to be preserved in the fossil record. The "suddenly" is the part that's hard to explain-- what changed to allow such extensive adaptive radiation? I'm no expert on these fossils, but I know several people who are. However, without an internet connection on the boat, I couldn't exactly email them for the answer. Luckily, this book has an answer: The Cambrian was preceded by a geological "snowball earth", and when that ended, atmospheric oxygen levels rose dramatically, allowing multicellular organisms to flourish (because you really can't be multicellular without an aerobic metabolism and oxidative phosphorylation).
If I were editing this book, I'd make each chapter half the words and fill the space with more figures. So many of the concepts would be better illustrated than explained, I feel like they missed the boat on that, even though they did include some very important ones (e.g., evolution of the eye). But if you are willing to do a little outside reading or skip some parts that are just too much, it's a good book. If I were looking to design a research project, this would be a good place to start, to find out the interesting questions about life.