Prairie dogs are burrowing rodents that live in grasslands. What makes the prairie dog a keystone species in the ecosystem?

OPTIONS:

A) Prairie dogs are the main source of food for wolves and coyotes in the grassland. B) Prairie dogs are the species with the largest number of individuals in the grassland ecosystem. C) They successfully compete with the other herbivores for grass and are a major threat to these species. D) Their tunnels act as conduits for rain water to seep into the ground, thereby promoting the growth of grass.

D) Their tunnels act as conduits for rain water to seep into the ground, thereby promoting the growth of grass.

Explanation:

A keystone species is an organisms whose presence and population defines the existence or balance of the ecosystem where they are found. Any negative influence on their population would drastically bring a change and imbalance in an ecosystem. Their presence and activities in the ecosystem is vital and beneficial to other organisms in the ecosystem.

Prairie dogs are keystone species in the grassland ecosystem where they are found because the tunnels they burrow improves soil aeration, fertility as well as water percolation, which encourages the growth of grass in grasslands. Seeds easily germinate also with this improved soil condition.