Scientific study of the population cycles of the snowshoe hare and its predator, the lynx has revealed that a. predation is the dominant factor affecting prey population cycling. b. hares and lynx are so mutually dependent that each species cannot survive without the other. c. both hare and lynx population sizes are affected mainly by abiotic factors. d. the hare population is r-selected and the lynx population is K-selected.

Question

Accepted Answer

Hello everyone. Let's look at our next question which of the following statements about the predator prey system is correct. Well it's always a good idea to glance over our answers and see is there anything really obvious we can eliminate right away, Bring down a number of answer choices. So let's just take a quick glance over all of them. Choice A. Says a growth in the predator population almost always result in the extinction of prey. Well this just doesn't make logical sense. If almost always pray goes extinct. When the predator population grows uh grows, that would not work because there are predators wouldn't have any food and would go extinct. So just from kind of logical consistency we can eliminate choice A. As an unrealistic answer choice B. A. Growth in the predator population results in a decrease of the population of prey choice. See a growth in the prey population results in a decrease in the population of predator. Well we'll just think through those a little further. But choice D the predator population has no influence on the prey population. Okay well again logically predators are eating prey. So the idea that the amount of predators would have no influence on the prey population just doesn't really make sense. So A. And D. Let's just toss out B. And C. Let's just think through this choice B. Says a growth in the predator population results in a decrease and the population of prey. Well we've got more predators so they eat more prey and so indeed we would expect the initial result to be a decrease in prey. So we'll go ahead and select choice B as a sensible correct answer to be thorough. Let's just double check choice. See a growth in the prey population results in a decrease in the population of predators. Again, if we see a growth in prey, well that would mean more food for predators. So we would expect that after a little gap we'd actually see a growth in the predator population as that allows them to reproduce more successfully and grow. So choice C. Is not correct. However, it is important to note, you know, for to have different types of questions about this that this is essentially a cycle. So if we think about it, let's, for example, start with our choice. See growth and prey population, we have a growth and predator population following after a little gap. Well eventually as a predator population grows, they're going to need to eat more and more prey and eventually the prey population will start to decrease. And as our prey population starts to decrease, what happens, our predator population will then decrease as a result because they're running out of food. So then the cycle will begin, prey population would go down predator population down, letting the prey population rebound as there are fewer predators to eat them. So we're gonna kind of go around and around in a cycle normally. So kind of just be aware of that if you had a different type of question about this system. See you in the next video.

Verified Solution

Key Concepts

Predation and Population Dynamics

R-Selected vs. K-Selected Species

Abiotic Factors in Population Ecology