b. Cheatgrass competes successfully with bunchgrasses for water and nutrients.c.Cheatgrass is somewhat fire tolerant.d. All of these are valid reasons. e. Cheatgrass is an annual, so there are seeds in the ground ready to grow any year.
What is the primary limiting factor that determines why no female animal can produce a very large number of very large eggs?
A student conducts a mark-recapture experiment to estimate the population size of sun-fish in a small pond near his home. In the first catch, he marked 45 individuals. Two weeks later, he captures 62 individuals, of which 8 are already marked. What is the esti-mated size of the population based on these data?
The proportion of offspring produced that survive, on average, to a particular age is called
For a species to be called 'invasive', it must _____.1be introduced to a new area.