Evolution, Planet, Ecology, Nature

Humans have a tendency to think of themselves as distinct from all other species, special, unique. Is this thinking correct with regard to Darwinian selection? Are we above other animals when it comes to selection? Some scientists believe that the Darwinian views of natural and sexual selection don’t apply to us because humans are extremely”ecologically flexible”, meaning that we have the ability to adapt to a number of types and changes of environment in a way that no other animal can. However, genomic information has provided the scientific community with proof that choice of phenotypic traits does occur in humans. This means that selection does act on humans, even if the extent at which it acts is not fully understood. This subject is of repute in the field of human evolution. Are humans still evolving, or is our species stagnant and not able to develop further?

Natural selection is the process described as the choice of biological traits depending on the sexual success of people carrying these traits. To put it differently, the”passing on” of specific traits is dependent on the reproductive success of the individuals. Sexual selection is the concept that animals develop certain traits or features that are not necessarily crucial for their survival but give them a higher likelihood of reproducing, by way of instance the mane of a lion, or the tail of a peacock.

Scientists have a good grasp on the roles sexual and natural selection play in most animal populations however, because of lack of suitable datasets, selection in human populations has yet to be fully understood. A study, conducted by Alexandre Courtiol and Virpi Lummaa in the University of Sheffield, looks at whether or not natural and sexual selection happened in this human population and extrapolated their findings to modern human populations. The analysis consisted of analyzing the opportunity for selection based on 4 factors in human life: achieving reproductive age, access to opposite sex, effective mating and fertility. They took into account the gap that wealth and sex could have on these points and divided the data into two classes: landowners and landless. This was done to exclude social standing as being a cause for greater reproductive success. They found evidence that both natural and sexual selection acted on this population.

This is to say, people able to survive to maturity and pass on their genes were better adapted than people not able to do so, and therefore chosen more often by the opposite sex.

Variance in mating success explained the greater variance of male reproductive success, compared to females. This higher variance of male reproductive success can be explained by the social situation of the time. Divorce and adultery were highly prohibited and only in the eventuality of a partner dying would you be able to remarry and continue to have children, continue to reproduce. Men remarried more often than women since women were open to marrying men much older than themselves. Reproductive success would be higher for men as a consequence of the fact that men have a longer reproductive life; there is no age limitation in guys for the ability to procreate. This isn’t typically seen in cases where the spouse is widowed. Once widowed, most females would not procreate again; they would cease to have reproductive success. The sexual selection observed in this population can be simply explained by the ability of men to replicate for more; this doesn’t give them greater fitness.

At this point it’s been observed that natural and sexual selection acted on this human population. The results of the study further revealed that it was sexual choice that offered the greater proportion of opportunity of choice. In other words, that sexual selection accounted for a higher proportion of the complete selection. Natural selection was still important, but not to the exact same degree.

The novelty of the study is that it shows higher chance of choice than any other research with human inhabitants. Procedures such as statistics of birth and death rates, and demographic surveys do not account for differences such as economic status, biological contrast and social standing.

Are humans above other creatures when it comes to choice? Assessing the data, Courtiol et al. found that the human population followed the identical intensity of Darwinian selection as that expected from any other animal inhabitants. This means that humans in this population were subject to the very same forces of choice due to any other animal population. Extrapolations can be reached from this analysis. This monogamous population showed both sexual and natural selection to the extent of other animal populations; would a modern population show the same degree of selection? The changes in social behaviour, technology, and culture seem to haven’t removed the evolutionary pressures of natural and sexual selection. If Darwinian selection operates in a strictly monogamous society then it is plausible that it would also function in a less monogamous population.

It is true that many of work has to be done in this field; however, new studies have been designed and carried out that promise to bring forth more info. It is exciting to think that scientists are delving into these questions. Are humans unique in the view of natural and sexual selection? Does our”ecological flexibility” set us apart from all other animals? It is my opinion that sexual and natural selection definitely play a part in our societies, but to what extent I remain unconvinced. Likewise to all people, I like being different from all other species.

Is Evolution Still Happening

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