Questions: Interactive Map 2.2 Hare Lynx A different species of hare, the jackrabbit, lives in the southwestern desert. Like other herbivores in its ecosystem (antelope, mice, and ground squirrels), the jackrabbit eats a variety of plant foods including grasses and wildflowers in the spring and summer, and the leaves of shrubs and trees in the winter. The shrubs and trees also provide hiding places from their predators. Predators include hawks, owls, coyotes, foxes, and other mid-sized carnivores. The jackrabbits are also bothered by ticks, fleas, and lice. Which factor might represent top-down regulation for the jackrabbit population? - grasses and wildflowers - shrubs and trees - rainfall needed for plant growth - hawks and owls

The answer is the fourth one: hawks and owls.

Explanation for each option:

1. Grasses and wildflowers: These are food sources for the jackrabbit and represent a bottom-up regulation factor. They influence the population by providing the necessary nutrients for survival and reproduction, but they do not exert top-down control.

2. Shrubs and trees: Similar to grasses and wildflowers, shrubs and trees provide food and shelter for the jackrabbit. They are part of the habitat and contribute to bottom-up regulation rather than top-down.

3. Rainfall needed for plant growth: Rainfall affects the availability of plant food and is a bottom-up factor. It influences the ecosystem by determining the abundance of plant life, which in turn affects herbivore populations like the jackrabbit.

4. Hawks and owls: These are predators of the jackrabbit and represent a top-down regulation factor. Predators control the population size of their prey by hunting them, thus exerting top-down pressure on the jackrabbit population.

In summary, top-down regulation involves factors that control a population from the top of the food chain, such as predators. In this case, hawks and owls are the top-down regulatory factors for the jackrabbit population.