characterized by the absence of life or living organisms

process where a community of animals leaves a habitat for part of the year or part of their lives, and moves to habitats that are more hospitable.

region at Earth's extreme south, encompassed by the Antarctic Circle.

to accept or allow something.

region at Earth's extreme north, encompassed by the Arctic Circle.

reason or set of reasons given with the aim of persuading others that an action or idea is right or wrong.

ordinary.

having to do with living or once-living organisms.

series of secondary changes that are triggered by the primary changes to a key species in an ecosystem.

to state as the truth.

contest between organisms for resources, recognition, or group or social status.

part.

an environmental state that must be present or exist in order for something else to exist or function.

desire to know more about a subject.

unplanned or temporary path.

to divert or draw attention away from something.

community and interactions of living and nonliving things in an area.

result or impact produced by an action.

able to be proved with evidence or experience.

conditions that surround and influence an organism or community.

data that can be measured, observed, examined, and analyzed to support a conclusion.

outside of something.

possible.

region where organisms go to eat.

central and important.

measurement of how fast something increases in size during a particular period of time.

involving the possibility of risk, loss, or harm

to influence or have an effect on something.

to carry out plans.

inside, or having to do with the inner part of something.

to break the uniformity or continuity of something.

an explanation of symbols and abbreviations used on a map, also known as a legend.

symbolic representation of selected characteristics of a place, usually drawn on a flat surface.

part of a map representing specific features of a place.

to determine the numeric value of something, often in comparison with something else, such as a determined standard value.

way of doing something.

natural signal, such as a change in temperature, to which animals respond by migrating to more hospitable habitats.

predictable movements, in time and space, of a group of animals or people.

path followed by birds or other animals that migrate regularly.

image or impression of an object used to represent the object or system.

to fill an area with too many objects or organisms.

having to do with the open ocean.

dangerous.

point of view or way of looking at a situation.

extreme north or south point of the Earth's axis.

total number of people or organisms in a particular area.

animal that hunts other animals for food.

animal that is hunted and eaten by other animals.

process of using evidence to make inferences or conclusions using logic.

to create offspring, by sexual or asexual means.

substances such as water, air, shelter, and food sources which are valuable in supporting life.

to correct or improve an existing material, often a written document.

distinctive relative size, extent, or degree.

an answer to a problem.

group of similar organisms that can reproduce with each other.

native, geographic area in which an organism can be found. Range also refers to the geographic distribution of a particular species.

person or organization that has an interest or investment in a place, situation, or company.

observation of a person, community, or situation.

ability to live.

something used to represent something else.

degree of hotness or coldness measured by a thermometer with a numerical scale.

process in which scientists and resource managers use technology to tag animals and map their movements.

to cause or begin a chain of events.

machine that produces power using the motion of wind to turn blades.

large national park in the U.S. states of Wyoming, Idaho, and Montana.