Terrestrial plants and animals have to contend with it. They expend more energy on this, and need to save energy for a rainy day . Not so with marine material, which grows much faster than terrestrial biomass. Overall, the terrestrial biosphere takes up more carbon each year than the marine ecosystem, but the carbon used in the biological production in the ocean turns over more rapidly than that on land. A population is a group of individual of the same species living in the same area at the same time sharing the same genetic information .
Population dynamics is the study of population changes with time.
If unchecked, populations grow exponentially . That is, they increase their population by a fixed percentage each year. An example is the elephant seal. In the late 19 th century, its numbers were reduced to 12 individuals. In the 1970s, their numbers were up to 60,000.