Relationship of predator and prey population growth

Lotka–Volterra equations - Wikipedia

relationship of predator and prey population growth

A predator-prey relationship tends to keep the populations of both species the growth or development of an organism, population, or process. how predators affect prey populations, and vice-versa; what stabilizes predator- prey interactions and prevents their The Development of Predation Theory. The Lotka–Volterra equations, also known as the predator–prey equations, are a pair of first-order nonlinear differential equations, frequently used to describe.

The fastest lions are able to catch food and eat, so they survive and reproduce, and gradually, faster lions make up more and more of the population. The fastest zebras are able to escape the lions, so they survive and reproduce, and gradually, faster zebras make up more and more of the population.

An important thing to realize is that as both organisms become faster to adapt to their environments, their relationship remains the same: This is true in all predator-prey relationships.

Lotka–Volterra equations

Another example of predator-prey evolution is that of the Galapagos tortoise. Galapagos tortoises eat the branches of the cactus plants that grow on the Galapagos islands. On one of the islands, where long-necked tortoises live, the branches are higher off the ground.

On another island, where short-necked tortoises live, the branches are lower down. The cactuses, the prey, may have evolved high branches so that the tortoises, the predators, can't reach them. Note, however, not just in this case but in any case of co-evolution and evolution, that there is always more than one cause that forces an organism to adapt, and though it is likely that the higher branches are to avoid the tortoises, it is also possible that it was a different cause, such as the sun, the ocean, or a different organism.

Well, at this point, with a low density of predators, it's gonna be much easier for them for find a meal, and it's gonna be much easier for the prey to get caught. So since it's more easy, it's easier for the predators to find a meal, you can imagine their population starting to increase.

Predator–Prey Relationships |

But what's going to happen is their population is increasing. Well, it's gonna be more likely that they're gonna, they prey is gonna get caught. There's gonna be more of their hunters around, more of their predators around.

So that population is going to start decreasing all the way to a point where if the population of the prey gets low enough, the predators are gonna have, they're gonna start having trouble finding food again, and so that their population might start to decrease, and as their population decreases, what's gonna happen to the prey? Well, then, there's gonna be less predators around, so they might be able to, their population might start to increase.

And so I think you see what's happening. The predator and prey, they can kind of form this cyclic interaction with each other.

And what I've just drawn, this is often known as the predator-prey cycle. And I just reasoned through that you can imagine a world where you can have the cycle between predator and prey populations. But you can also run computer simulations that will show this, and even observational data out in the field also shows this. One of the often cited examples is interactions between, between the snowshoe hare, which would be the prey in this situation, and the Canadian lynx, which would be the predator, the predator in this situation.

And you see a very similar cycle to what I just drew, kind of just reasoning through it, and this, right here, is actual data.

Predator prey relationships

You see the passage of time here, and this is a long passage of time. We're starting in the early 's going all the way to the early-mid 's.

relationship of predator and prey population growth

So it's roughly years of data that we're showing, and in the vertical axis, you have thousands of animals and we're plotting both the population of snowshoe hares and Canadian lynx in a certain area on this chart. And as you see, when the prey population is high, when the prey population, sorry, when the predator population is high, when we have a lot of the Canadian lynx around, that we see a lower, a lower population of the prey, of the hare.

But then as, since you have a low population of the food in this situation, the predator population starts to decrease. So let me draw an arrow here. The predator population starts to decrease and, let me do that same blue color.

relationship of predator and prey population growth