1. WHEEEEE ! Whale Evolution: Different Lines of Evidence
by Larry Flammer - ENSI webmaster
(Becoming Whales: Discovery of Whale Fossils)
(Whale Ankles and DNA)
WHEEEEE !

2. What are we Doing Today?
Whale fossil hunt
Whale ankle comparisons
Whale DNA comparisons
WHALE EVOLUTION

3. Becoming Whales

4. Diversity of Whales Today
Mysticetes (baleen whales):

5. Diversity of Whales Today
Odontocetes (toothed whales):

6. But Where Did They Come From?
ONE OF DARWIN’S IDEAS…
… I can see no difficulty in a race of bears being rendered, by natural selection, more and more aquatic in their structure and habits, with larger and larger mouths, till a creature was produced as monstrous as a whale.
Charles Darwin, The Origin of Species, 1859 (first edition), Chapter 6: Difficulties on Theory
Darwin was wrong about the BEAR (he removed this idea in later editions), but spot-on with the process – NATURAL SELECTION.

7. Here’s a Peek into the Past…
So, Where DID Whales Come From?
Here’s a Peek into the Past…

8. Moving in…
Notice that the earliest MAMMALS… were TERRESTRIAL - with LEGS !

9. But WHALES SWIM; they DON’T WALK ON LAND !
So - Where DID Whales Come From?
What would the earliest whales look like?

10. The Earliest MODERN WHALES…
NOW
Only go back to about 23 mya… the beginning of the MIOCENE…
5 mya
MIOCENE
23 mya
Great swimmers… but NO WALKING LEGS !
65mya

11. HOWEVER ! from the EOCENE !
We DO have some whale-like fossils, with strange teeth,
NOW
5 mya
MIOCENE
23 mya
from the EOCENE !
65mya

12. But… Where’s the Eocene?
NOW
NOW
Miocene: Earliest modern whales
23 mya
34 mya
EOCENE
55 mya
4.5bya
65mya

13. OK! So, where shall we look for Eocene Fossils?38
Mountains of Pakistan
The Tethys Sea 55
India Moved North…
…Squished into Asia…

14. Where shall we look?
Pakistan
Lots of exposed marine Eocene rocks in the Pakistan mountains

15. Let’s Hunt Whale Fossils…
Work in pairs
Open Your Eocene Timeline
Remove whale strips from plastic bag
Listen for descriptions and timing
Place whale strip on timeline
Wait for next “discovery”

16. Eocene Epoch Timeline

17. Early Whale Teeth
in Dorudon
~ 36 mya
1936

18. Eocene Epoch Timeline
Dorudon 36 mya (39-36 my) 1936

19. Early Whale Teeth… in a 4-legged mammal?
a Mesonychid called Pachyaena
~ 55 mya
… with tiny hooves!

20. Eocene Epoch Timeline Dorudon 36 mya (39-36 my) 1936
Pachyaena 55 mya (58-34 mya) 1955

21. Early Whale Teeth …and hooves, too! In Pakistan… ~50 mya WITH LEGS !
Pakicetus - an early whale
~50 mya
Gingerich - Pakistan

22. Eocene Epoch Timeline Dorudon 36 mya (39-36 my) 1936
Pakicetus 50 mya ( Pakistan)
Pachyaena 55 mya (58-34 mya) 1955

23. Early whale teeth in… Basilosaurus ~37mya and LEGS, too…
1990 Gingerich - Egypt

24. Eocene Epoch Timeline Dorudon 36 mya (39-36 my) 1936
Basilosaurus 37 mya (39-36 mya) 1990
Pakicetus 50 mya ( Pakistan)
Pachyaena 55 mya (58-34 mya) 1955

25. Early Whale Teeth ~46 mya Rodhocetus - an early whale
And tiny hooves, too !
~46 mya
early Gingerich - Pakistan

26. Eocene Epoch Timeline Dorudon 36 mya (39-36 my) 1936
Basilosaurus 37 mya (39-36 mya) 1990
Rodhocetus 46 mya (early Pakistan)
Pakicetus 50 mya ( Pakistan)
Pachyaena 55 mya (58-34 mya) 1955

27. Eocene Epoch Timeline Transitional form? Predict What? (draw) Where?
Dorudon 36 mya (39-36 my) 1936
Basilosaurus 37 mya (39-36 mya) 1990
Rodhocetus 46 mya (early Pakistan)
Transitional form?
Predict What? (draw) Where?
Pakicetus 50 mya ( Pakistan)
Pachyaena 55 mya (58-34 mya) 1955

28. Early Whale Teeth… in Pakistan
With tiny hooves, too !
Ambulocetus - the “walking whale”
~48 mya
late 1994 Thewissen

29. Eocene Epoch Timeline Dorudon 36 mya (39-36 my) 1936
Basilosaurus 37 mya (39-36 mya) 1990
Rodhocetus 46 mya (early Pakistan)
Ambulocetus 48 mya (late Pakistan)
Pakicetus 50 mya ( Pakistan)
Pachyaena 55 mya (58-34 mya) 1955

30. Ambulocetus
Carl Buell

31. Whale Phylogeny, 1994 Hans Thewissen

32. But Mesonychids are EXTINCT!
SO, Who are the Closest Living Relatives of Whales?
Maybe Hooved Mammals?: = Ungulates: Two Orders:
33-38: Hooved animals and ANKLE evidence
Perissodactyls (odd-toed)
Artiodactyls (even-toed)

33. Perissodactyls Odd-Toed Ungulates
Rhinos & Tapirs
Horses & Zebras

34. Artiodactyls Even-Toed Ungulates

35. Leg Anatomy…
Heel Bone
Ankle Bone

36. Ungulate Foot Bones…
FOSSIL HORSE
FOSSIL PIG
Heel Bone
Ankle Bone

37. Whale Ankles? Compare ankle bones… Pig Pakicetus Mesonychid
two small ridges
Mesonychid
Prim. Artiodactyl
Prim.Perissodactyl
Ankles Compared (with arrows showing…)
one big ridge

38. Whale Phylogeny, 2001 Philip Gingerich
Early whale ankles indicate close relationship with artiodactyls (even-toed ungulates)
Mesonychid ankles indicate they are closer to perissodactyls (odd-toed ungulates)

39. But WHICH Artiodactyls?
Will DNA Tell Us?
40-48: DNA analysis indicates hippos are the most closely related living animals to whales.
Let’s Compare DNA…

40. DNA Analysis Compare segments of beta-casein gene

41. DNA Analysis Compare segments of beta-casein gene

42. DNA Differences

43. DNA Differences

44. DNA Differences Fewer than five differences…
2 porpoise & sperm whale
3 porpoise & right whale
3 sperm whale & right whale
3 sperm whale & hippo
3 porpoise & hippo
3 right whale & hippo
3 giraffe & deer
3 giraffe & cow
4 cow & deer

45. DNA Differences Seven differences…
7 pigs and peccaries
DNA Differences Remaining species…
Higher numbers - more distantly related

46. Phylogenetic Tree - WHALES Based on DNA Differences

47. Provisional Phylogeny - Cetartiodactyls

49. Whale Evolution Recap
Fossil teeth link whales to the 4-legged mesonychids of the Paleo-Eocene
Tiny hooves on mesonychids and early whale toes tie whales to the ungulates
Ankle bones of early whales point to artiodactyl ungulates as the closest relatives of whales

50. Whale Evolution Recap
DNA confirms the artiodactyl connection and points to hippos as the closest cousins of whales
Consilience: these multiple independent lines of evidence strengthen, narrow and confirm the hypothesized close relationship between whales and artiodactyls

51. Whale’s Closest Cousin: Hippos

52. If possible, play a little humpback whale “music” here!

53. FAREWHALE!

54. Have a Whale of a Time!
FINI