Every organism depends on living and nonliving things to survive. Ecology is the branch of science that examines the relationships organisms have to each other and to their environment. Scientists who study those relationships are called ecologists.

There are many different ways to study ecology. Some types are landscape ecology, population ecology, and behavioral ecology.

Landscape ecology deals with spatial distribution, patterns, and behaviors across large geographical areas. Landscape ecologists might study the impact of development on a particular species of native grass in a specific area. One type of grass may be resistant to chemicals, for example, indicating the area would be ideal for agricultural development.

Population ecology studies the rise and fall in the number of a species. A population ecologist may compare the population of a species near a new food source to a population that lacks access to that food source. The new food source may increase the numbers of the species, or, if the food source is contaminated, reduce it.

Behavioral ecology studies the different ways organisms evolve and adapt to changes in their habitat. Behavioral ecologists often study mating patterns, or what characteristics male and female animals prefer when seeking to reproduce. Behavioral ecologists study bird songs or plumage as they relate to mating patterns, for example.

When ecologists study a particular animal, they examine what the animals food sources are, how it reproduces, what its predators might be, and the characteristics of its habitat. They also study how the animal lives in that habitat, including migrations, shelter, population, and how the species interacts with other animals and plants in its habitat.