By Gerardo Rocha


Yep. Just as you read it. All individuals possess individual variations that are either the result of mutations within their own cells as they reproduce, or the product of reproduction by their ancestors. As cells mutate, genetic code is rearranged and sometimes modified, this can cause new traits to appear and either benefit or harm the organism. Reproduction of two organisms renders a combined product of two sets of DNA, which is itself a new variation
Big image


As we mentioned above, when two organisms reproduce, an original combination is produced. This combination has traits from both parents, and can retain the hair color of the father, the eye color of the mother, either one's height or speech patterns, etc. Darwin had no idea that DNA existed or much less that it played such a factor in the process of evolution. He did, however, recognize that something must happen between the two organisms to render such a product.
Big image


More Offspring are Produced than can Survive

Just as in the job world where more graduates are available than jobs are, organisms struggle because not all of them are bound to make it. Some will be eaten, some will become sick, some are undesirable mates and won't pass on their genetics, either way these organisms are abundant. This is a biological impulse that guarantees that the parent's genetics will be passed on. Animals like the octopus, which lay hundreds of eggs, are more likely to have one of them survive than a whale, which has one child at a time, which can be killed and eaten.
Big image

Reproduction and Survival Are Not Random

If you want to get anywhere in life, you have to deal with things as they come and adapt. This is also true in the natural world. Organisms are faced with the great challenge of "Natural Selection", wherein they have to develop the best adaptations such as camouflage or immune systems that can withstand whatever their environment can throw at them. An organism doesn't just "get lucky" in life, a series of adaptations were put in place and the circumstances played with them to create an advantage. Natural Selection is a great way to prove how species evolve based on which genes get passed on, which also dictates the way the species is headed.
Big image


Freeman, S., & Herron, J. C. (2007). Evolutionary analysis (No. 575.8 FRE). Upper Saddle River, NJ: Pearson Prentice Hall.

Gould, S. J. (1982). Darwinism and the expansion of evolutionary theory.Science, 216(4544), 380-387.

Grant, P. R. (1999). Ecology and evolution of Darwin's finches. Princeton University Press.

Ao, P. (2005). Laws in Darwinian evolutionary theory. Physics of life Reviews,2(2), 117-156.