Nancy visits a local reservoir where she feeds ducks and other birds. Every time she feeds them she notices that they fight for the best pieces and some do not get any. All living things struggle to get the necessary amount of food, water, and shelter. What is the term for this struggle? * A. overproduction B. natural selection C. variation D. Competition

An ecologist is studying the effects that a population of predators is having on a population of a prey. he used data from the field to produce this graph. which conclusion can draw from the graph?

What are the 3 types of artificial cloning

Which of the following statements is a scientific claim? a. the early solar system had large amounts of water; so, the oldest objects in the solar system should also be abundant in water. b. earth is shaped like a sphere even if not all of the scientific observations related to its shape support this idea. c. the mass of the universe is much greater than current models predict; it is not possible to explain this inconsistency. d. planet earth is abundant in water, but there is no way to scientifically determine from where earth's water originated.