The most conspicuous ways in which natural selection has affected our lineage is that is has caused us to become bipedal animals with huge brains, flat faces, long legs and shorter arms, highly dexterous fingers and opposable thumbs. In nature By avoiding changes in the environment, by removing invasive species, or by relocating endangered species to new habitats, humans can affect. the process by which nature rewards those individuals better adapted to their environments with survival and reproductive success. It works at the level of genes, sections of DNA that encode for proteins serve as the software of life. For example, among the genes the researchers predicted to be under negative selection are those involved in muscular dystrophy and in Usher syndrome, the most common cause of congenital blindness and deafness in developed countries.
Natural selection is the process by which nature selects organisms or species which fit closely to the environmental conditions. The question of how it can negatively affect humans is thus related to drastic changes in environmental conditions such as climate change. If climate changes become worse in the near future, the criteria for natural selection will also change. It has been argued a lot that changes in climate would not be in favor of currently living organisms, hence, nature will start eliminating humans along with other organisms.
Here is an example: if global warming results into increase in temperature, ice will melt and lead to sea level rise. Most of the continents will be covered with water. On the other hand, terrestrial animals including humans are not able to survive in the water which will result in their elimination.
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