New News Biology #50

Variation & Evolution

A group of individuals in a population are all different, because of different phenotype which show observable characteristics. The interaction of genes and the environment can result in different characteristics.

We all eat different foods, get different amounts of sunlight, smoke or don’t smoke cigarettes, drink different amounts of alcohol, etc. Meaning that our height, eye color, and other traits are different as well.

Why is there so much genetic variation?

Because mutations (proteins may be different), changing the phenotype altogether. Most mutations don’t have any visible effects, those that do are commonly bad for us, though there are slight cases that have a beneficial effect. For example, a mutation made an individual run faster, had faster reflexes, had stronger muscles, or a higher intelligence to outwit the enemy.

In this case, this individual is more likely to survive, more likely to reproduce, and likely to pass this important trait to their offspring, and that cycle continues. This is called ‘survival of the fittest’ or ‘natural selection’, which was coined by Charles Darwin who noticed all that.

With all this information, he came up with the concept of evolution, that the inheritance of certain characteristics in a population over many generations could lead to a change in the species or the development of a new species altogether. This meant that all living organisms and animals and species that we see today must have developed from one single ancient organism, a common ancestor. It took quite a long time for Darwin’s theory to become accepted by the public, though it has since been proven multiple times through stuff like fossil records.

In summary, evolution gives rise to genetic changes due to natural selection, that result in phenotype best suited for the environment. And when two types of one species vary so much that they now cannot produce fertile offspring, we call this the emergence of another, different species. Thanks Darwin!