WHAT TO REMEMBER IN THIS LESSON ON EXTINCTION?

Discover extinction: what it is, why species vanish, and the different types of extinction.

EXTINCTION Extinction happens when the last individual of species dies out. This process is irreversible.Types of Extinction:1) Functional extinction occurs when individuals remain, but the odds of sustainable reproduction are low, i.e., the species is effectively extinct even though individuals remain.2) Local extinction happens when a species become extinct in a particular area but continues to exist elsewhere. Reintroduction of the species from other regions can address local extinction issues.3) Background extinction is the gradual process of becoming extinct. Using fossil records and ice core drills, scientists estimate that the average annual background extinction rate is 1:5 species for every million species.4) Mass extinctions happen when the extinction rate dramatically increases as large populations of organisms die out in a relatively short period.When does extinction occur?Extinctions occur when the environment of a species changes faster than the species can adapt. In other words, a species' adaptations are no longer sufficient in allowing that species to acquire and compete for resources.Extinctions can be local, widespread, or global.Extinctions are either natural or man-made.Extinctions occur naturally (background extinctions – 1-5 species per year).Nearly all of the species that have existed on Earth have gone extinct.There have been five major mass extinctions in geological history, and recovery from these events took millions of years. Why Do Animals Go Extinct? Watch the video 2mlT0HeVLv4to learn more about extinction.