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7 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Constraints and Bad Design
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Giraffe's neck:
The laryngeal nerve loops around the aorta instead of taking a direct route from brain to larynx. In the giraffes the detour is up to 4.6 metres |
What sort of constraint does say a long neck impose? Why would it have developed this way?
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Vestiges and Atavisms
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A species of Dung Beetle does not fly and yet under its carapace still has tiny wings. Why unless an ancestral species had functional wings?
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Tiny unsuable wings?
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Vestiges and Atavisms
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Females have all the usual genitalia and yet in mating they just get stabbed straight in the ovaries by the male.
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Why might a throwback to previous ancestors way of protection from mating be helpful to female bed bugs?
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Vestiges and Atavisms
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Hen's teeth. Why can a hen's body be convinced to produce teeth? The DNA pathway is still partially there, just unused.
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Atavism- a characteristic that is a throwback too an ancestral species. Inactive genes are reactivated.
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Embyros
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The first stages of all embryos look very similar.
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What is similar? This suggests a similar body plan that is then changed slightly to create new organisms.
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Intermediates in the fossil record
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Tiktaalik- intermediate between fish and tetrapods. It has a flat head and skeletal features similar to tetrapods but scales, gills (and lungs) and fins.
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Intermediates evidence that all species have evolved through small changes.
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Pseudogenes
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One of six identical beta-globin genes is missing in humans, chimpanzees and gorillas. Does it or did it serve a function?
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are genes that exist in DNA but aren't used to create any functional protein. Why is half of our DNA on functional?
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