Znaci sto vise jedes veci ces narasti i sto vise gledas vece ce ti oko biti jel
Evolution has continued in anatomically modern human populations, which are affected by both natural selection and genetic drift. Although selection pressure on some traits, such as resistance to smallpox, has decreased in modern human life, humans are still undergoing natural selection for many other traits. Some of these are due to specific environmental pressures, while others are related to lifestyle changes since the development of agriculture (10,000 years ago), urban civilization (5,000), and industrialization (250 years ago). It has been argued that human evolution has accelerated since the development of agriculture 10,000 years ago and civilization some 5,000 years ago, resulting, it is claimed, in substantial genetic differences between different current human populations.
Particularly conspicuous is variation in superficial characteristics, such as Afro-textured hair, or the recent evolution of light skin and blond hair in some populations, which are attributed to differences in climate. Particularly strong selective pressures have resulted in high-altitude adaptation in humans, with different ones in different isolated populations. Studies of the genetic basis show that some developed very recently, with Tibetans evolving over 3,000 years to have high proportions of an allele of EPAS1 that is adaptive to high altitudes.
Other evolution is related to endemic diseases: the presence of malaria selected for sickle cell trait (the heterozygote form of sickle cell gene), while the absence of malaria and the health effects of sickle-cell anemia select against this trait. For example, the population at risk of the severe debilitating disease kuru has significant over-representation of an immune variant of the prion protein gene G127V versus non-immune alleles. The frequency of this genetic variant is due to the survival of immune persons.
Recent human evolution related to agriculture includes genetic resistance to infectious disease that has appeared in human populations by crossing the species barrier from domesticated animals, as well as changes in metabolism due to changes in diet, such as lactase persistence.
In contemporary times, since industrialization, some trends have been observed: for instance, menopause is evolving to occur later. Other reported trends appear to include lengthening of the human reproductive period and reduction in cholesterol levels, blood glucose and blood pressure in some populations.