Presentation on theme: "Describe the variation pictured above. Speculate as to how natural selection in different environments has produced such large differences."— Presentation transcript:
Describe the variation pictured above. Speculate as to how natural selection in different environments has produced such large differences.
Brainstorm a situation where the ideas of variation, natural selection, and adaptation apply to non-living things. Share your answer with a partner and be prepared to explain to the class.
NOVEMBER 19, 2010
Homologous structures are structures which are similar even in widely differing species. It is evidence of divergence from a common ancestor. The form is similar even though the function may not be. Tool userRunnerPouncerFlyersSwimmer itc.gsw.edu/.../histgeol/paleo2/homol1.htm
The ancestor started with four primitive but functional wings. How have the form and function diverged in contemporary insects?
The pitcher plant and venus fly trap live in environments with poor soil and need extra nutrients. The poinsetta has to attract insects in order to promote pollination. The cactus has to protect its moisture from pests. Describe a possible variation as a first evolutionary step from a regularly shaped leaf toward each of these specialized homologous structures.
Describe the form and function of the pictured structures (antennae and leg). Compare them, and use the vocabulary word homologous in your sentence.