Because the ecosystem has a carrying capacity that limits how many of a species can live in that area or then overpopulation will happen and the animals that surpass that will die.
2. what are factors that determine whether a population increases or decreases
(use each factor in one-sentence example)
The hawk population is low because they hunted all the rabbits and they got low in numbers so all the hawks cannot feed themselves in turn the population decreasing, so the rabbit population has time to grow more since it is not being hunted as much since less hawks are there.
The hawk population has gotten bigger in numbers and there are lots of rabbits since before that the hawk population has been small so they start hunting a lot of rabbits in turn of that the rabbit population is decreasing since there has been a sudden increase of hawk population.
3. Give a reason why the human population of earth has continued to increase so much for the past 100 years?
Because the human population has not reached the carrying capacity that the whole world has of humans and we have been getting resources excessively like cutting down too much trees for homes, making lots of electronic devices, mining all the minerals and oil that will eventually run out. Until one point where the earth can no longer support us then there will be a sudden decrease of humans because we have surpassed the carrying capacity of the world on us.