Read the following passage from the Blology Department at University of California,Berkeley. Northern elephant seals have reduced genetic variation because hunting by humans reduced their population sizo to as fow as 20 individuals at the ond of the 19th century. Their population has since rebounded to over 30,000, but their genes still carry the marks of this near extinction; they have much less genetic variation than a population of southern elephant seals that was not hunted as intensely. Which of the following best describes how the population has evolved? The population has not evolved because there was no change in allele frequencies The population has not evolved because it has grown The population has evolved because it has grown The population has evolved because there was a change in allele frequencies.

## Step 1<br />The problem is asking us to determine how the population of Northern elephant seals has evolved based on the given passage. The passage provides information about the population size of the Northern elephant seals, which was drastically reduced due to hunting by humans. This reduction in population size led to a decrease in genetic variation.<br /><br />## Step 2<br />The passage also mentions that the population has since rebounded to over 30,000, but their genes still carry the marks of this near extinction. This indicates that the population has undergone a change in allele frequencies, which is a key characteristic of evolution.<br /><br />## Step 3<br />The options provided are:<br />- The population has not evolved because there was no change in allele frequencies<br />- The population has not evolved because it has grown<br />- The population has evolved because it has grown<br />- The population has evolved because there was a change in allele frequencies<br /><br />## Step 4<br />Based on the information provided in the passage, the correct answer is "The population has evolved because there was a change in allele frequencies". This is because the population's genetic variation has decreased due to a drastic reduction in population size, which is a change in allele frequencies.