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Evolution in Process 15.3 pp. 289-292 Evolution is a continuous process that is always going on, just really slowly (needs lots of time)

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Presentation on theme: "Evolution in Process 15.3 pp. 289-292 Evolution is a continuous process that is always going on, just really slowly (needs lots of time)"— Presentation transcript:

1 Evolution in Process 15.3 pp. 289-292 Evolution is a continuous process that is always going on, just really slowly (needs lots of time)

2 Evolution in Process 15.3 pp. 289-292 Homologous structure = similar feature found in many different species Comes from some common ancestor Examples: different beaks for different birds Forelimbs (arms) in high order animals Similar species,different job Homologous structure = similar feature found in many different species Comes from some common ancestor Examples: different beaks for different birds Forelimbs (arms) in high order animals Similar species,different job

3 Evolution in Process 15.3 pp. 289-292 Analogous structure= feature that does the same job but is very different in structure Wings on birds (arms) vs. wings on insects (just wings) Webbed feet on ducks vs. fins on fish Different species, same job Analogous structure= feature that does the same job but is very different in structure Wings on birds (arms) vs. wings on insects (just wings) Webbed feet on ducks vs. fins on fish Different species, same job

4 Evolution in Process 15.3 pp. 289-292 Coevolution = 2 different species in close relationship that evolve together Predator – prey : gazelle get faster to escape, cheetah get faster to catch the gazelle Plant – pollinator: hummingbirds and the flowers they feed on Coevolution = 2 different species in close relationship that evolve together Predator – prey : gazelle get faster to escape, cheetah get faster to catch the gazelle Plant – pollinator: hummingbirds and the flowers they feed on

5 Evolution in Process 15.3 pp. 289-292 Convergent evolution= different species evolve features to do a similar job in a similar environment The conditions they live in are similar so they need to do similar things to survive Sharks – dolphins : these have converged Different species, same job Convergent evolution= different species evolve features to do a similar job in a similar environment The conditions they live in are similar so they need to do similar things to survive Sharks – dolphins : these have converged Different species, same job What does it mean to converge? Related to analogous structure. What does it mean to converge? Related to analogous structure.

6 Evolution in Process 15.3 pp. 289-292 Divergent evolution= very similar species evolve different features to do different jobs Different habitats so they evolve different ways to survive Sea snakes – desert snakes Penguins -- ducks Artificial selection: dog breeding, cattle breeding (these are done by humans, not nature) Similar species, different job Divergent evolution= very similar species evolve different features to do different jobs Different habitats so they evolve different ways to survive Sea snakes – desert snakes Penguins -- ducks Artificial selection: dog breeding, cattle breeding (these are done by humans, not nature) Similar species, different job Related to homologous structure.

7 Evolution in Process 15.3 pp. 289-292 Examples of divergent evolution. Where on the graph to species diverge? Examples of divergent evolution. Where on the graph to species diverge?


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