Myths about Nose
If you believe that our nose shape is inherited from our parents then it’s not true. Believe it or not, our nose shape is based on the climate we live instead of our parent’s genes. According to a recent study, it is found that the shape of our nose is formed by a long process of adaptation to our local climate. Whether it is big, small, broad, narrow, long or short, tuned up, hooked and others shapes, believed to be impacted by the climate we live.
What is Genetic Drift
According to the international team of researchers, the reason for the change in shape can be due to a natural phenomenon “Genetic Drift”.
The change in the frequency of a gene variant in a population due to the random sampling of organisms is the Genetic drift. The researchers claimed that divergent in Natural selection, variation in the natural selection process can be a reason also.
In natural populations, both of them do not act in isolation; both forces are always at play together with mutation and migration. The evolution is the product of both mutation and drift, not of drift alone. Even when selection overwhelms other, it only acts as a variant.
While natural selection has a direction that can be traced heritable adaptations, genetic drift has no direction, guided by the mathematics of chance. The researchers have noted that an important function of the nose and nasal cavity is to condition inspired air before it reaches the lower respiratory tract.
A variety of nose measurements, looking at the width of nostrils, the height of nostrils and nose ride length, nose protrusion were considered. They showed that width of nostrils is largely correlated with the Temperature and absolute humidity.
The positive direction of the effects indicates that wider- noses are more common in warm-humid climates, while narrow noses in cold dry climates. The narrower nostrils seem to alter the airflow so that the mucous-covered inside the nose can humidify and warm the air efficiently.
The purpose of the nose is to condition inhaled air so that it is warm and moist. People with narrower nostrils probably fared better and had more offspring than with the wider nostrils, in colder climates.
What sexual selection has to do with nose
The cross-population in nose selection may occur through sexual selection. People may choose their mate simply because they find smaller or larger nose more attractive.
If the entire crowd thinks that the smaller is better than those with large nose have fewer successes in reproducing and fewer large nose people will be in the crowd.
Ecological selection and Sexual selection could reinforce each other, according to the researchers. However, whether this connection between the two types of selection was important in the evolution of the nose requires further investigation.