Patterns of Evolution Macroevolution Evolutionary patterns and processes

Macroevolution Evolutionary patterns and processes that occur over long periods of time. n Six

Mass Extinction Periods in Earth’s history where entire ecosystems collapsed. n Large groups of

Adaptive Radiation A single species of animal evolves into many different species that lives

Convergent Evolution Unrelated organisms in the same environment have body structures that look and

Coevolution Two or more species evolve in response to changes in each other over

Developmental Genes Animals share similar genes that are active early during embryonic development. n

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Patterns of Evolution

Macroevolution Evolutionary patterns and processes that occur over long periods of time. n Six Topics Mass Extinction Adaptive Radiation Convergent Evolution Coevolution Changes in Developmental Genes

Mass Extinction Periods in Earth’s history where entire ecosystems collapsed. n Large groups of organisms went extinct due to density-independent problems. Example: K-T Extinction n n An asteroid hit the earth causing major tectonic activity – earthquakes, volcanoes. Massive climate change over a short period killed the dinosaurs.

Adaptive Radiation A single species of animal evolves into many different species that lives in different ways. n Mammals today evolved from a group of species that looked like shews.

Convergent Evolution Unrelated organisms in the same environment have body structures that look and act the same. n Examples Fins on dolphins, penguins and sharks Wings on birds, bats and insects

Coevolution Two or more species evolve in response to changes in each other over time. n n Butterflies and flowers Cows and plant poisons

Developmental Genes Animals share similar genes that are active early during embryonic development. n Hox genes Small changes in the Hox genes can lead to large developmental differences.

Hox examples