Download Patterns of - westbranch.k12.oh.us

April 19, 2018 | Author: Anonymous | Category: , Social Science, Anthropology, Human Evolution
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Patterns of Evolution • Macroevolution- large scale evolutionary patterns and processes that occur over long periods of time. – Extinction – Adaptive radiation – Convergent evolution – Coevolution – Punctuated equilibrium – Changes in developmental genes

Extinction • More than 99% of species that have ever lived are now extinct -no longer exists on earth • Competition for resources/change in environments • Can be gradual for individuals or can be catastrophic mass extinctions that affect entire ecosystems

Adaptive Radiation • When a single species or small group of species evolve into many diverse forms over time. • Examples: Mammals evolved, finches evolved

Convergent Evolution • Unrelated organisms come to resemble each other • Animals and plants • Sharks, dolphins, seals, penguins

Coevolution • The process by which two species evolve in response to changes in each other over time

Punctuated Equilibrium • Long, stable periods with little change in species interrupted by brief periods of more rapid change

Developmental Genes and Body Plans

• Small changes in genes can result in large changes in an organism • Hox genes - “master control” genes for animal body plans • One change in a gene can result in wingless, one pair, or two pairs

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