Amphibians have been greatly affected by the loss of habitat from humans. They have also been subjected to losses by predators, pollution, and fungal infections. These are more endangered than any other vertebrate group. Bats have had losses because of fungal infections, particularly in the Americas. Beehives have been lost by pesticide ingestion.
WAYS HUMANS MIGHT EVOLVE There have been many theories on how humans will evolve in the future. Some say were will have high foreheads and large brains but this hasn t been borne out in archaeological and fossil records. Others say that humans will not evolve further; however, the human genome has been changing over time. Most of the changes in human evolution so far has been behavioral and physiological rather than morphological. As we have already discussed, there have been many hominid species over time, including the arrival of Homo sapiens in Ethiopia nearly 200,000 years ago. Over time, migrations of humans have led to the different races of humans. Because of the connectivity of the human races, there has been no recent speciation of humans. Even so, genes have changed to a significant degree, even in the last 5000 years, mostly because of adaptations to the environment. Lactose tolerance and intolerance are some of these changes that have occurred. Because of extreme advances in global transportation, the gene pool has become mixed in humans. It might further bring out the homogenization of the human species. Technology has placed a monkey wrench in natural selection so that babies do not die in great numbers and people with once fatal genetic diseases now do not die to the greatest extent that once happened. One interesting shift in human evolution is that college students have fewer children and later starts in parenting than their less-intelligent high school classmates. This may mean that genes for lesser intelligence may increase in the population, driving down the average intelligence in the human race. This has not yet been found to be the case. An argument against this is that intelligence is not necessarily entirely heritable. On the other hand, ADHD and Tourette s syndrome have higher heritability and could increase in society. Alcoholism may also increase due to heritability of this tendency. Humans may in the future become different due to genetic engineering but we are a long way away from having this happen. One other theory is that humans could become symbiotic or synthesized along with machines. Some have forecasted that humans could upload their minds to robots or computers, leading to an intimate connection to them. Advanced artificial
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