What does a food chain diagram illustrate?
a. an ecosystem's water cycle
b. multiple pathways of feeding in an ecosystem
c. one pathway of feeding in an ecosystem
d. an ecosystem's carbon cycle

Examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. polyploidy is creating new species. the two populations are not interbreeding freely. hybrid offspring of the two populations begin to appear. one species will increase into a population size twice as large as the other species.

Which of the organisms listed below performs nitrogen fixation? a. legumes b. plants c. bacteria d. fungi

What are some possible consequences of preventing prescribed burns and natural wildfires