Natural Selection Odds and Ends

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Natural Selection Odds and Ends
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A mimetic system Batesian and Müllerian Mimicry
Aposematic coloration Parallel geographic
variation
Micrurus 6 species. Highly venomous Fixed front
fangs Neotropical Elapidae Pliocercus 1 or 2
species. Mildly venomous Fixed rear
fangs Colubridae
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Does aposematic coloration work? Plasticine
models Forest floor on white paper and on
forest floor
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Experiment carried out in natural habitat
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Resemblance does not have to be perfect to
confer protection
Significant differences
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• Is avoidance of aposematic coloration innate?
• Naïve motmots (Neotropical birds)
• Caged birds presented with
• 1. coral snake models
• 2. models of natural prey species.

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A famous Müllerian mimicry complex.
Each species with subspecies defined by color
pattern and geography.
What happens at subspecific boundaries?
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Phenotypic plasticity environmentally induced
variation operating on common genetic background.
Geometrid moth Nemoria arizonaria
Phenology relationship between climate and the
timing of ecological events.
Water Crowfoot Ranunculus aquatilis
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Polymorphic mating strategies
Uta stansburiana Side-blotched lizard Polymorphism
males
Color and behavior determined by levels
of prolactin and testosterone in early
development. Fixed for life. 1. Large
territories, many females 2. Small
territories, one female. 3. Non-territorial, sneak
copulations from 1. Morph frequencies
shift between generations depending on success
of a particular tactic.
1.
2.
3.
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Infanticide and fitness
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Siblicide and fitness
Brown booby