ECOLOGY
BIODIVERSITY AND ITS CONSERVATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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competition within the population will increase
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the surviving elephant seals will be better able to adapt
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Inbreeding will be less frequent among the remaining population
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the elephant seals will be more vulnerable to environmental changes
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Detailed explanation-1: -The northern elephant seal was almost hunted to extinction in the 1800s. By the late 1890s, approximately one hundred seals were left, reducing the gene pool of the population. What will be the consequence of this reduction? The elephant seals will be more vulnerable to environmental change.
Detailed explanation-2: -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-3: -Today, the northern elephant seal population has rebounded to approximately the size it was before hunting. It’s estimated that there are 150, 000 individuals, with 124, 000 in California waters.
Detailed explanation-4: -Northern elephant seals have reduced genetic variation most likely due to being hunted. Hunting reduced their population size to as few as 20 individuals at the end if the 19th century. Since then their population has rebounded to over 30, 000 but the genes still carry the marks of their bottleneck.
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.