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The Evidence For Evolution. Artificial Selection . Artificial Selection . Wild-type vs. Domesticated Corn. Artificial Selection . Artificial Selection . Russian geneticist Dmitry K. Belyaev . Artificial Selection . Piebald coat color in dometsicated animals and foxes. After 8 – 10
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Artificial Selection Wild-type vs. Domesticated Corn
Artificial Selection Russian geneticist Dmitry K. Belyaev
After 8 – 10 • generations: • Changes in coat color • Floppy ears • Rolled tails • After 15 – 20 generations: • Foxes with shorter tails and legs • Underbites / overbites • Barking!
Absolute (Radiometric) Dating = based on principle that isotopes decay to daughter isotopes at a constant rate The Fossil Record Half-Life = time required for 50% of parent isotope to decay
Absolute (Radiometric) Dating = based on principle that isotopes decay to daughter isotopes at a constant rate The Fossil Record Half-Life = time required for 50% of parent isotope to decay
Your measurements indicate that a fossilized skull you unearthed only contains about 1/16th the carbon-14 of the skulls of present-day animals. What is the approximate age of the fossilized skull? Try It!
Relative Dating KT Iridium Layer – Italy KT Iridium Layer – Newfoundland
Morphological Homology – Anatomical Mammalian forelimbs
Vestigial Structures Vestigial Bones in Snake and Human
Vestigial Structures Python with vestigial appendage
“How far more interesting does out study become when we regard every production of nature as one which has a history” – Darwin, 1859 Blind Salamander Flightless Kiwi
Why? Seems Odd? QWERTY Key Arrangement
At least as good, possibly better. Why don’t we use it? DVORAK Key Arrangement
“Evolution is like modifying a machine while it’s running” – Karl Liem
Don’t Be Fooled By Analogous Structures! What do they tell us about?
Homology or Analogy? Porcupine’s Quills and Cactus’s Spines Cat’s Paw and Human Hand Owl’s Wing and Hornet’s Wing
Developmental Homologies Match and Order the Embryos!
Molecular Homology 7% 1.2% 1.6% 3.1%
Piecing Together the Evolution of Whales What are the different types of evidence that were used?