In this chapter, Darwin is very concerned about the topic of natural selection. He makes the point that just like in artificial selection where breeders might choose a particular feature in organisms and preserve this feature by breeding organisms with this trait more than organisms lacking the trait. Darwin mentions that nature acts in the same way, choosing some variations which are beneficial to the organisms in a specific environment and these variations are the ones which are said to be advantageous. If organisms do not naturally have variations which make them adapt easier to their environment they’re more likely to die out and be extinct. Darwin also discusses the concept of sexual selection which plays a huge role in species evolution. …show more content…
With respect to variations that are advantageous to survival, he notes that a slim wolf is more likely to run faster, catch prey and escape from predators. He also states that plants with attractive petals and sweet nectar is more likely to attract more insects that will serve as agents of pollination for that plant. Regarding variations that are useful for sexual section but not directly useful for survival in nature, he mentions brightly colored feathers in male birds and the ability to perform the mating call well. These traits, although useful for finding mates and reproducing might not be useful for escaping from prey. On the issue of isolation and natural selection, Darwin talks about organisms on islands and the importance of the weaker organisms dying out leaving those who are best suited for the environment to reproduce and ensure longevity of the species. In the absence of geographical isolation, organisms might be introduced into a species or some organisms might develop environmental plasticity, and while this is in itself not a bad thing, it disrupts natural selection from occurring. On the topic of species divergence, the Galapagos finches are a great example of how natural selection, over a length time, leads to formation of a new species that is very different from the parent