Biogeography

the study of species and ecosystem distribution across time

Major Topics:

Alfred Russel Wallace

Alfred Russel Wallace was a co-founder of natural selection whose ideas mirrored Darwin's, but more importantly, he is known as the father of biogeography. One of his major theories was aposematism (anti-predator adaptations). They include warning coloration, peculiar phenotypes or actions to warn a predator that none of them benefit if it preys upon them. Wallace had also hypothesized that reproductive isolation is a favored mechanism of evolution that prevents the creation of hybrids (which often spawns unviable or sterile organisms). Lastly, he had created a boundary line (Wallace Line) that separated Asian and Australian flora and fauna, which are related to species of the respective continents.

Evolutionary Biology

Evolutionary Biology can explain how an organism can become more fit to adapt to a sudden introduction of a population or environment. For example, the smog from the Industrial Revolution has caused the lighter peppered moth populations to die out due to a loss of camouflage. On the contrary, natural selection selected the darker peppered moth populations and they reproduced rapidly. The shift of phenotype frequency is a case of directional selection.

Ecology

Ecology can explain why organisms are distributed where they are. An organism interacts with its population, which interacts with other populations and forms a community. A community then interacts with abiotic factors, such as weather and climate to form an ecosystem. Introducing a foreign element into an ecosystem can cause devastating changes, because the community is adapted only to the current organisms. Inversely, if you add an organism that is unfit for an ecosystem, then they will die out.

Continental Drift

Continental drift can explain how fossils appear in unreasonable locations. The theory of Pangaea suggests of a supercontinent where all modern day continents were combined in a large landmass. If an organism crossed the boundary where continents met, then they would have left fossils on two remote areas. Also, the continents all fit together (South America and Africa being obvious) when combined without their shorelines.