In the book Genetic Entropy & the Mystery of the Genome the author says that the genome cannot be old because the genome is "decaying". Decay is a very subjective term, but in this case he means that the fitness of humans is going down not up. Is it true that our genome is decaying over time, and that the fitness of humans is decreasing? Here is a quote from the book, that might explain his argument:
Kondrashov, an evolutionist who is an expert on this subject, has advised me that virtually all the human geneticists he knows agree that man is degenerating genetically. The most definitive findings were published in 2010 in the Proceedings of the National Academy of Science by Lynch.4 That paper indicates human fitness is declining at 3–5% per generation.There is really no debate on current human genetic degeneration.
Perhaps this more shines more enlightenment in my question. This idea of human fitness going "down" is my main concern. Essentially, in his book he claims that because we are going "down" (meaning fitness is declining) not "up" (whatever that means) our genome must therefore be young. If I understand the issue correctly, mutations "create new information" by creating different proteins or leading to an abnormal protein products. However, I thought that the force of natural selection should be strong enough to get a rid of those genes that are so and so responsible for our fitness declining.
Feel free to point me to similar questions that may been helpful or are similar to this one.