When wild plant and animal populations are logged, fished, or hunted, only the oldest or largest individuals tend to be taken. Many of the commercially important species are long lived and are slow to begin reproducing. If harvesting is not regulated carefully and exploitation is intense, what impact does harvesting have on a population's age structure? How might harvesting affect the population's life table and growth rate?

Video transcript

Hey everyone. Let's take a look at this question together. Which of the following populations will have a faster growth rate. So let's recall what we've learned in the past about populations and the mechanisms that help explain that growth rate. So we know that the rate of growth can be determined by graph where we have here time and here we could have the number of people because we're talking about reproduction in terms of the growth. And so when we want to have a faster growth, we want to have a larger amount of people in that short period of time. And so to get to this point in time and this many people that means that our population would need individuals to reproduce at an early age or answer choice A. Because when we're looking at that we want to start the reproduction early. And so that way it is the shortest amount of time to grow that population. And so looking at answer choice B. We see population in which individuals reproduce at a late age. It would be too late because here and here we'd have a longer time time to get to that point where as we're already at that point about here in an earlier age. So that would make answer choice B incorrect and then answer choice C. We have a higher proportion of senior citizens that curve would look something like this because the age would be too high and they wouldn't have a lot of time left to have that. And so C. Is incorrect and then D a small number of reproductive individuals would have the same kind of graph as the senior citizens because there wouldn't be as many people to reproduce. So it would be the same kind of curve as the senior citizens, which makes answer choice a the only correct answer. I hope you found this video to be helpful. Thank you and goodbye.