Part Three.
Role of Natural Selection
Because of their large size, elephants can't reach the ground with their mouth. Natural selection solved this problem over the millennium by lengthening the animals' upper lip and nose into a trunk. Over time, natural selection (mutations) has also worked in favor of these Asian elephants because they have learned to travel in herds to protect each other since poaching and ivory hunting has become such a huge issue. They have also evolved when it comes to tusk development. Unlike their African relatives where both genders can develop tusks, only male Asian elephants can produce tusks due to the over hunting that is hurting and changing their populations and environment because of industrialization.
The Asian elephant speciation was due to the fact that this population was separated by human impact and changes in the land-forms. This split happened simply because of species isolation. The African elephants were isolated to be stationed in Africa while the Asian elephants split off and were present in Asia. Over time, as climates and environmental factors were established, two entirely new species were created. |
Timeline
The "mean" trait here that is being selected against is the trait for both males and females to have tusks. As poaching increases (the y-axis variable), the more natural selection will act in favor of both extremes rather than the original trait. One extreme is that male Asian elephants have tusks and the other extreme in that female Asian elephants do not while the middle extreme (the mean) is in the middle and is the lowest (the x-axis variables).
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In Conclusion...
Due to human interactions through hunting and poaching Asian elephants, a bottleneck effect has occurred to their population because it had killed off a massive amount of Asian elephants which leaves a scar in their genes and reduces genetic variation. Overall, human impacts plays a very big role in how the Asian elephants survive because it determines where and for how much do they live. Industrialization and the harm of hunting has taken away the rights for many Asian elephants to live freely in an environment that is equally theirs'. Also, due to these environmental and population changes, natural selection has to act and change many factors of this species' life such as population size, location, life expectancy, and adaptations. These precious animals, who can do minimum amount of harm unless provoked, are being endangered and even underlining extinction.