whale hunt

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Whale Hunt Searching for whale fossils

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a powerpoint for teacher led presentation of the SENSI becoming whales lesson plan

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Page 1: Whale hunt

Whale Hunt

Searching for whale fossils

Page 2: Whale hunt

Primitive whales

• Durodon• 25-45 mya• Different to modern whales– Distinctive teeth

Carl Buell

Page 3: Whale hunt

The search for the land relative• A group called Mesonychids had the same

kind of distinctive teeth as primitive whales

• They also had hooves, suggesting that whales may be related to cow, horse, deer, pigs

• Interesting but not convincing!

Page 4: Whale hunt

• Notice that you have a very big gap between the Durodon and the mesonychids.

• In 1983, a skull was found that had the same teeth as Durodon, as well as some other whale like features including whale-like ear bones.

• Found in Eocene deposits in Pakistan

Page 5: Whale hunt

Pakicetus• 50mya• Although Pakicetus has a land animals body, it’s head

is a distinctive whale shape with whale-like earbones• Had hooves• Probably lived near river and fed on fish

Carl Buell

Page 6: Whale hunt

Basilosaurus• The next piece of the puzzle was found by in Eygypt in

1990• The tiny hind limb of Basilosaurus• Basilosaurus had been known since 1830’s but the

hindlimb had never been found• It is thought to be the first fully marine whale, living in

deep oceans, around 37mya

Page 7: Whale hunt

Hind limbs

• The Basilosaurus hindlimb was too small to carry the animal on land, but was still functional

• It provides good evidence of a transition from land to water

Basilosaurus

Modern whale

Page 8: Whale hunt

• In 1994 in Pakistan another 4-legged fossil was found that was more recent than Pakicetus

• It had shorter legs, whale-like ear bones, and the nostril had moved to between the eyes and tip of snout

Pakicetus Rodhocetus Modern whale

Page 9: Whale hunt

Rodhocetus

• 46mya• Had small but functional legs. Still had tiny

hooves on its toes

Page 10: Whale hunt

• Notice now that you have a gap between Pakicetus and Rodhocetus where a large change has occured.

• Talk with your group about what an intermediate between these two animals might look like.

• Make a sketch.

Page 11: Whale hunt

• In late 1994 an almost complete skeleton of “the walking whale” was found

• It is about the size of a sea lion and probably swam like an otter.

• It had whale-like ears and little hooves on its toes.

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Ambulocetus

Carl Buell

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Whale valley - Egypt

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