Evolution is the survival of the most fit in a species so that the next generation might have a better chance of survival and potentially living longer then the previous generation. When an individual in the species is deemed “unfit” in the eyes of natural selection, they will die before they are able to reproduce and pass their genes on to offspring. All species evolve from generation to generation. From the time of Charles Darwin to today’s era, evolution has been studied countless times. Studies of many different insects, birds, and animals have supported the theory of evolution. But what about humans? Has technology diminished evolution impact on our species? Or does evolution affect us more than we realize?
While evolution may be a quite controversial topic in today’s world, a new study of a massive genetic sample supports evolution of the modern human race. This study of human evolution suggests that evolution does, in fact, have an affect on the human genome. “‘If a genetic variant influences survival, its frequency should change with the age of the surviving individuals,’ says Hakhamanesh Mostafavi.” Many genes (along with ages of the individual) were analyzed. Two genes were found to have an impact on survival because as the age increased, the less often the gene was found.
One gene is a variant of the APOE gene linked to Alzheimer’s and it was found in almost none of the females over the age of seventy. The other is a variant of the CHRNA3 gene linked to heavy smoking and in men, it was absent in most middle-aged and older men. These two genes decrease one’s chances of survival so natural selection runs its course and those individuals do not live as long. This supports the theory of evolution because of the gene’s correlation between the frequency of occurrence and the survival of the carrier.
Genetic sampling is a good way for us to predict life-expectancy and allows us to take precautionary measures to ensure the overall thriving of our species. We are able to see the specific genes that allow our population to be more evolutionarily fit. While technology and genetic altering hinder natural selection and evolution from occurring, natural selection is still relevant to our species and still has an effect on us.
One criticism of the study was that while these genes have a correlation with the age of the individual carrying them, it had seemingly no effect on the probability of them passing on their genes. However, humans naturally live long enough to see the generation after their offspring. This is why women live long after menopause has occurred. Grandparents are able to provide support and care for their children as well as their grandchildren which helps those younger generations to survive. This trait of our species is unique and does not occur as often in others.
This topic is very interesting and it was fascinating to read and learn more about it because evolution is a seemingly inapplicable topic for human genetics. These discoveries about humans and our evolution are very supportive of the theory of evolution. Evolution obviously plays a role in the genetics of our species. While it may not affect our life expectancy as much as it once did, we are able to see its relevance in the human genome.
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