Speciation

Biology Index

Where are we going with this? The information on this page should increase understanding related to this standard:  Identify chronological patterns of change and communicate that biological evolution is supported by multiple lines of empirical evidence that identify similarities inherited from a common ancestor (homologies).

Article includes ideas, images, and content from Troy Smigielski (2022-01)

Source, 2022-03

Speciation

(Okay, you're making up words now!)

Speciation is the formation of a new species. It is the process by which a population evolves to become different, distinct species.

What could be a cause of speciation? What could cause one species to become two different species?

There are a variety of things which can cause speciation, but reproductive isolation in a population is one major cause of speciation.

Reproductive isolation is the inability of a species to breed and successfully produce offspring. This is a major cause of speciation because without reproduction, a species cannot survive. Instead of extinction of one species, this causes the creation of two new species that are able to successfully reproduce.

There are 5 major types of reproductive isolation.

Behavioral Isolation

Behavioral isolation occurs when populations of the same species develop differences in courtship rituals or other types of behaviors.

Geographic Isolation

Geographic isolation occurs when populations of the same species become separated by geographic barriers such as rivers, mountains, bodies of water, etc.

This is also referred to as allopatric speciation.

Temporal Isolation

Temporal isolation occurs when populations of the same species develop differences in the time or season that they breed.

Mechanical or Chemical Isolation

Mechanical or chemical isolation occurs when the reproductive structures or chemical barriers of species do not allow organisms to interbreed.

Ecological or Habitat Isolation

Ecological or habitat isolation occurs when species that could interbreed do not because they live in different areas, even if they are within the same general ecosystem.

Two birds living in different environments will never meet, so they will not be able to reproduce.