Biology 102 - Biogeography Flashcards

Biogeography Concepts

• Biogeography: Study of organisms' geographic distribution and ranges.
• Macroevolution: Evolution occurring at a level above species, illuminating broader evolutionary trends.

Reasoning Methods

• Inductive reasoning: Moves from specific observations to general principles.
• Deductive reasoning: Derives specific instances from general constructs.
• Hypothetico-deductive reasoning: Validates scientific theories by testing logical assumptions against evidence.

Biogeography Questions

• Two main questions: Why are species distributed as they are? Why does biota diversity vary by region?

Natural History Disciplines

• Four disciplines in biogeography: Geology, paleontology, phylogenetics, and ecology aid in understanding species distribution.

Geology and Related Fields

• Geology: Examines Earth's structure and past life impacts on current landscapes.
• Paleontology: Studies extinct organisms and fossilized remains.
• Phylogenetics: Investigates evolutionary relationships and origins of species.
• Ecology: Explores interactions between organisms and their environments.

Species Range Changes

• Species ranges can change due to biotic (adaptation and dispersal) and abiotic (climate change, tectonic events) factors.

Biotic and Abiotic Influences

• Biotic factors: Include adaptations to new habitats and long-distance dispersal.
• Abiotic factors: Encompass climate shifts, eustatic changes (sea level), and tectonic movements.

Types of Biogeography

• Ecological biogeography: Examines short-term ecological processes affecting organism distributions.
• Historical biogeography: Focuses on long-term processes influencing geographic distribution and speciation history.

Notable Biogeographic Lines and Events

• Wallace's Line: Distinct separation of Asian and Australian faunas.
• The Great American Interchange: Species dispersion post-adaptation leading to competition.

Island Biogeography Theory

• Proposed equilibrium theory suggests islands have fewer species due to unique ecological processes rather than time constraints.

Species and Distance Relationship

• Relationship observed: Greater distance from mainland correlates with fewer species, while closeness leads to higher species diversity.

Mass Extinctions Overview

• Notable extinction events include the Ordovician, Devonian, Permian, Triassic, and Cretaceous-Paleozoic events.

Details of Major Extinction Events

• Ordovician Event: ~440 million years ago, significant glaciation led to a 49% genus extinction.
• Devonian Event: ~375 million years ago, marked the transition of life to land, with 50% genus extinction.
• Permian Event: ~252 million years ago, the largest extinction (83% genera extinct), caused by multiple geological factors.
• Triassic Event: ~200 million years ago, led to 50% genus loss, primarily terrestrial.
• Cretaceous-Paleozoic Event: ~65 million years ago, resulted in a 70% species extinction linked to meteor impacts.

Terminology in Extinction

• Extinction: Complete disappearance of a species, e.g., Dodo.
• Extirpation: Localized extinction from a part of the range, e.g., Snail darters.

Evidence of Extinction Causes

• Geographic evidence of meteors: Notable sites like the Yucatan Peninsula, with associated volcanic activity and global rock layer changes.

Post-Extinction Diversification

• Rapid diversification often follows mass extinctions due to the availability of habitats and resources previously occupied by extinct species.

Test your knowledge on biogeography and macroevolution with these flashcards. This quiz covers key terms and concepts related to the study of organisms' geographic distribution and evolutionary processes. Perfect for Biology 102 students looking to reinforce their understanding.