Life Ascending surprised me truth be told. As I mentioned in my first post I was concerned that Lane would focus too much upon anthropomorphic view and was pleasantly surprised to see that this was not the case. Lane does focus heavily upon a human centered viewpoint, which is to be expected but I was pleased to see that he based many of his arguments in other contexts other than the human one. One example of this is the death chapter where Lane describes how death could have arisen from a war between bacteria and viruses developing an arms race of toxin and anti-toxin. Death is traced from its basic roots through the incorporation of mitochondria into host cells and the advent of multicellular life explaining how death could be brought into the host cell via a fully formed apparatus in mitochondria, and how death would be preserved as a mechanism to keep differentiated cells working as a cohesive unit. This allows Lane to bring the evolution of death and aging into the human context discussing antagonistic pleiotropy and free radical affects. Lane uses these smooth transitions from different aspects of evolution to the human perspective to great affect. These transitions capture the average readers attention while simultaneously educating them about aspects of evolutionary biology they would never think of on their own.
Also the more I read the more I became convinced that Lane's praise of natural selection was not as overbearing as I had feared at first. Natural selection is still described in a glowing light but Lane points out repeatedly that natural selection can only within the historical context of evolution and is not goal oriented. While this might seem like beating a dead horse to students in an evolution class, but when viewed from the perspective of a member of the general populace trying to learn more about evolution it helps show how natural selection actually works. I also have changed my mind about Lane's chosen topics as I appreciated how they were presented. The topics were kept broad an attention was applied to how they evolved outside of humanity.
The final thought I have from the death chapter is over Lane's argument about antagonistic pleiotropy, mainly how can we expect it to evolve in the future. If people start having children later and later as is the trend in modernized countries what evolutionary changes can we expect?
Great post Logan! It's good that Lane didn't stick strictly to human examples and that he included the necessary caveats on the importance of natural selection. I like your description of the evolutionary origins of death in viruses and bacteria. Pretty mind boggling to think about! That's an interesting question you close with. I would guess that if whole populations of humans are reproducing later in life, selection would have a greater ability to act against deleterious mutations or detrimental pleiotropic effects that occur later in life. This could result in a significantly longer human lifespan. Rather than people "saving themselves for marriage", maybe we should save ourselves for retirement instead...
ReplyDeleteHa! Good one, Phil.
ReplyDelete