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The assortment of species on earth; within and between ecosystems; and the variation in the genetic compostion of a species


A community of various organisms interacting with each other within a particular physical environment


In terms of species, restricted to only one region or area


Information that refutes or supports a claim or hypothesis; information that leads to the develpment of a claim or hypothesis


A process in which something changes gradually or by intervals over time. In biology, changes in the genetic composition of a population that eventually give rise to other diverse life forms.

evolutionary tree

A branched diagram for classifying taxa that represents a hypothesis about the history of descent of groups of taxa


An observation or calculation that shows the presence or state of a condition or trend


A series of populations of a single species or several species descended from a common ancestor

phylogenetic diversity

A measure of biodiversity using the pattern of the relationships of lineages to one another over time.


The ability to meet a community's present needs without compromising the ability of future generations to meet their own needs.


Level of classification, such as genus or species


The plural of taxa, it is a group of (one or more) organisms, which a taxonomist adjudges to be a unit.


An exchange of one thing for another; giving up something that is a benefit or advantage, in exchange for some other benefit or advantage. It usually involves balancing benefits and risks.

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