Here are the two books that I plan to read, following my interest in biology and of course, the existence of Alien Life.
The life as we know it, must started simply. It’s the scientific consensus that approximately 3.77 billion years ago, the first life arose from non-living matters via a process called abiogenesis. It’s also the scientific consensus that after the abiogenesis, life got to where it is today primarily via evolution and natural selection. The process works roughly like this: over successive generations, biological populations pass down heritable characteristics to successive generations, and due to mutation, the next generations will be slightly different than one another and from their parents ( evolution). Natural selection, a process that favors fitter offspring over the lest fit one, will in turn responsible for weeding out the less fit one and maintain or improve the population fitness in the environment. It might be counter intuitive, but given enough time, evolution and natural selection can work wonders, such as producing human who is capable of launching space probes and designing nuclear weapons.
Life is obviously rare; or else given the billion of billions of planets, we would be overwhelmed by alien signals and technologies by now. And given that we haven’t seen the definite evidence of an alien life, can we tell how alien life looks like?
Obviously we can, says Arik Kershenbaum, a zoologist and animal communications researcher at the University of Cambridge. The same force or process– evolution– that gives rise to life as we know it today here on earth, will also operate on other planets, should life arise.
But what is life? This simple question stumps so many great minds. Obviously if you are reading this, you are alive. And so is a cat, or a dog, or even a bacteria. But it’s not so simple to exactly define what life is. There are over 100 definitions of life; after reviewing them, Edward Trifonov, a Russian-born geneticist found that they seem to be common only on one thing: life is a self-reproduction with variations. But obviously, self-reproduction with variations cannot be all that is to Life. A computer virus can also reproduce with variations, but we don’t call it life.
NASA’s definition works out a little better, though longer as well: “Life is a self‐sustained chemical system capable of undergoing Darwinian evolution”. NASA is in the business of detecting alien life forms, so having a precise and good definition for Life is of paramount importance. But according to this definition, a real virus is a life, which a lot of people might find it counter-intuitive. Also tying the “Darwinian evolution” to life is problematic. “Seedless” grape is not produced by Darwinian evolution, and can’t undergo Darwinian evolution, but we still call it life, no?
There are so many interesting questions and answers I expect to encounter and learn as I plow through these two books, I hope that I can give a good book review after finish reading them. So stay tuned for this space!
PS: I found the above two books via two excellent reporting pieces in Quanta Magazine. For those of you who want to read serious scientific reporting, Quanta Magazine is a good resource, do check it out!