Relatives and Relatedness

Relative and Relatedness

Identical Twin
1=100%
Sibling, Parent, Child
1/2=50%
Uncles/Aunts, Nephews/Nieces, Grandparent/child, Half brothers/sisters
1/4=25%
First cousins
1/8=12.5%
Second cousins
1/32=3.125%
Third cousins
1/128=.78125%

The facts that Dawkins has stated here, helped me clarify how genetically similar I was to each one of my family members. Although I don’t have an identical twin, I do have every other type of relative mentioned on this table. I honestly thought that I would be more closely related to my half brothers, than my aunts, uncles, and grandparents, since I have so much more in common with them than I do with most other relative of mine. I also never would have expected to have such a small genetic relationship with my second and third cousins. The percentage shows, that your relatedness with them, is almost the same thing as your relatedness with a complete stranger. The statistic which made me doubt the most though, was that identical twins are 100% similar to each other. Genetically yes, they are the same, but in terms of traits and personality, twins are very different. I have personally met several identical twins in my life, and could easily declare that one might be willing to save the other, while the other wouldn`t. In this case, would the altruistic gene be passed on to the next generation? This can probably be explained with how the environment affects people rather than their genes. There might be a possibility that the “Green Beard Altruism Effect” (mentioned on Pg. 89), will not always come into play for identical twins, even though the statistic says it should. They each develop minds of their own which ultimately influence their decision to be altruistic or not.

At the end of the chapter, Dawkins does assure this idea. He too, knows that the only person you are 100% related to is yourself. Therefore, he declares the following, "I contain 100 per cent of my genes...I am the only individual that any of my selfish genes can be sure of." (Dawkins Pg. 106).