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Adaptation. Ch 15 section 2. Natural Selection. Results in adaptation – a population becomes better suited to its environment Adaptation can also refer to a derived trait, one that has come about by natural selection. inherited characteristic. chance of survival. ADAPTATION. VOCAB
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Adaptation Ch 15 section 2
Natural Selection Results in adaptation – a population becomes better suited to its environment Adaptation can also refer to a derived trait, one that has come about by natural selection.
inherited characteristic chance of survival ADAPTATION VOCAB Any ___________________ that increases an organism’s ______________ = _____________ http://www.wildlife-traps.com/skunks.html http://www.atomtigerzoo.com/photos/images/20060421233733_duckfeet.jpg http://www.3kitty.org/travelrama/Photos/123-21-4x6.jpg
Camouflage-the ability to belnd in with your environment Allows organisms to become almost invisible to predators
Plant adaptations • Tropisms- a plants growth response to an external factor. • 3 types • Phototropism • Gravitropism • Thigmotropsim
Phototropism • Plant growth in response to light
Gravitropism Plant Growth in response to gravity
Thigmotropsim • Growth/movement in response to touch • Ex:vines
Sources of Variation • Mutations or genetic changes occur infrequently in a cell but frequently in a population, particularly a large one. • Genetic recombination through sexual reproduction, including crossing-over during meiosis.
Pages 438-441 Speciation and Patterns in Evolution
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Speciation • When some members of a population become separated from the group and change so much that they can no longer mate with members of the original population. • 2 Types: 1. Allopatric Speciation 2. Sympatric Speciation
Allopatric Speciation • A physical Barrier divides a population which gives rise to a new species. • Takes a LONG time • Most common
Sympatric speciation • A new species forms without a physical barrier. • Usually occurs in plants