Question

Write an explanation based on natural selection for the high incidence of tusklessness among female elephants in Gorongosa. Like all good scientific explanations, your explanation should include a claim, supporting evidence, and scientific reasoning to link the evidence to the claim. Use the Scientific Explanation of Evolution by Natural Selection chart

Answer 1

Argument: A trend toward an increased incidence of tusklessness will result in decreased population sizes in the

future.

Claim: In the long term, tusklessness in African elephants is not beneficial to populations, even when heavy

poaching is occurring. So, as tusklessness increases, elephant population sizes will decline.

Evidence: Although poachers kill elephants with tusks, elephants rely on their tusks for survival. Elephants use

their tusks to strip bark off trees for food and to dig up water and minerals from the ground. Male elephants

also use their tusks in competitions with other males for females.

Reasoning: Tuskless elephants are probably not as healthy as those with tusks, as they cannot eat bark off trees

and are unable to dig for water and minerals. During harsh conditions such as droughts, elephants without

tusks would be less likely to survive. Male elephants without tusks are also more likely to be injured during

mating competitions. If too many males are injured or killed, there may be a decline in reproduction.

Over time, many of the tuskless elephants will die or be unable to reproduce, so the population’s size will

decrease.

Step-by-step explanation: