Mallory went snorkling on vacation. during her snorkling adventure she came across a coral reef. all the coral that makes up
the reef is
an ecosystem
a population
the community
a temperate zone.

An ecosystem.

Explanation:

A coral reef is home to fish, sea turtles, and more. There are living components and nonliving components.

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".