Question

Most of the year, the hermit thrush, a North American songbird, eats a diet consisting mainly of insects, but in autumn, as the thrushes migrate to their Central and South American wintering grounds, they feed almost exclusively on wild berries. Wild berries, however, are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to complete their migration. One possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack.Which of the following, if true, most seriously calls into question the explanation given for the thrush’s diet during migration?(A) Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.(B) Insect species contain certain nutrients that are not found in wild berries.(C) For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.(D) Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.(E) There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.

Answer 1

Answer: (A) Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.

Step-by-step explanation:

Migration is a process in which the organisms migrate to location different than their native habitat. The factors that can be responsible for this is unsuitable season in the native habitat, lack of food and mates.

According to the given situation, the Hermit thrushes when switch to berries those were previously exposed to insect diet may experience scarcity of nourishment. Thus will remain undernourished and cannot migrate in autumn season due to lack of potential to complete a long migratory distance and may also die.