EVOLUTION
HARDY WEINBERG EQUILIBRIUM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Genetic Drift Occurred/Genetic Bottleneck:the few individuals left behind were the seals that passed on the specific gene pool.
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Genetic Drift Occurred/Founder Effect:the few individuals left behind were the seals that passed on the specific gene pool.
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Natural Selection Occurred/Survival of the Fittest:only the strongest northern elephant seals survived in the 1800’s and that restricted gene pool exists today.
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Adaptation Occurred:Some seals were able to adapt to the hunting environment and they survived to pass on their genes.
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Detailed explanation-1: -How is the lack of genetic variation related to the hunting episodes of the 1800’s? Genetic Drift Occurred/Genetic Bottleneck: the few individuals left behind were the seals that passed on the specific gene pool.
Detailed explanation-2: -Hunting reduced the population size of the northern elephant seal to as few as 20 individuals at the end of the 19th century. Their population has since rebounded to over 30, 000, but they have much less genetic variation than a population of southern elephant seals that was not so intensely hunted.
Detailed explanation-3: -An example of a bottleneck Northern elephant seals have reduced genetic variation probably because of a population bottleneck humans inflicted on them in the 1890s. Hunting reduced their population size to as few as 20 individuals at the end of the 19th century.
Detailed explanation-4: -Currently, the future of Northern elephant seals is uncertain and researchers lack the ability to determine what will happen to the population in the face of environmental stresses such as pollution, disease, or coastal development.
Detailed explanation-5: -Conservation Status Northern elephant seals are not presently endangered. At one time, however, this species was thought to have been hunted to extinction. They were presumed extinct by the 1880’s, after being exploited by hunters and whalers seeking to use the animals’ thick layer of blubber as an oil source.