Biogeography Lecture Summary

These flashcards cover key concepts from the lecture on biogeography, including definitions, important figures, and principles that govern species diversity and distribution patterns.

What is biogeography?

The study of biological lineages in the context of both space and time, focusing on biodiversity and its evolutionary and ecological geography.

What drives patterns of species diversity?

Factors such as latitude, elevation, precipitation, area, and distance influence species diversity and colonization.

What is the immigration curve in biogeography?

A graphical representation showing that the rate of arrival of new species declines as the number of species established on an island increases.

Define the extinction curve.

A graphical representation indicating that as more species establish on an island, the rate of extinction increases due to increased competition.

What is S* in the context of island biogeography?

The number of species established on an island when the rate of arrival of new species is balanced by the rate of extinction of established species.

What is T* in island biogeography?

The rate of turnover, or number of changes in the species list for the island, per unit time at equilibrium.

What is the area effect in island biogeography?

The principle that larger islands or land areas support more species due to greater habitat diversity and lower extinction rates.

What does the distance effect refer to in biogeography?

The observation that islands farther from a source of potential colonists tend to have fewer species due to lower immigration rates.

Who is Alfred Russel Wallace?

A naturalist known as the father of modern biogeography, who defined six biogeographic realms.

What is Wallace’s Line?

A biogeographic boundary that separates the distinct faunas of the Oriental and Australian regions, first identified by Wallace.

What is the significance of the species-area relationship (SAR)?

The relationship that demonstrates how larger areas support more species, first formalized by botanist Olaf Arhennius.

Give an example of a species influenced by continental drift in biogeography.

Ratites, such as emus and ostriches, evolved as their ancestral continent Gondwana broke apart into current landmasses.

How did continental drift affect species distribution?

Continental drift led to isolation of landmasses, allowing independent evolution of species within these regions.

What did MacArthur and Wilson propose?

The equilibrium theory of island biogeography, which describes the balance between immigration and extinction rates on islands.

What did the study by Stuart Pimm on Hawaiian birds reveal?

It showed that the likelihood of successful introduction of new species declines as the number of established species increases, indicating competitive exclusion.

What impact did the Yucatan event have on biotic regimes?

It marked the end of the dinosaurs and significantly influenced the evolution of various species due to changes in environmental conditions.

What role does habitat diversity play in species richness?

Greater habitat diversity on larger islands leads to increased species richness as it provides more niches for different species.