Becoming Whales Whale Evolution: Different Lines of Evidence by Larry Flammer - ENSI webmaster http://www.indiana.edu/~ensiweb/home.html http://www.indiana.edu/~ensiweb/lessons/whale.ev.html (Becoming Whales: Discovery of Whale Fossils) http://www.indiana.edu/~ensiweb/lessons/wh.a%26d.les.html (Whale Ankles and DNA) Becoming Whales

What type of creature is a whale? Video

Diversity of Whales Today Mysticetes (baleen whales):

Diversity of Whales Today Odontocetes (toothed whales):

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

Let’s go on a whale hunt!

Whale Fossils Diagrams… Work in pairs On the whiteboard create an Eocene Timeline (55 mya to 34 mya) Remove whale strips from envelope Read descriptions and place whale strip on timeline

Eocene Epoch Timeline

Early Whale Teeth in Dorudon ~ 36 mya 1936

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

Early Whale Teeth …and hooves, too! ~50 mya WITH LEGS ! Pakicetus - an early whale ~50 mya 1983 - Gingerich - Pakistan

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

Early Whale Teeth ~46 mya Rodhocetus - an early whale And tiny hooves, too ! ~46 mya early 1994 - Gingerich - Pakistan

On your white board draw a prediction for the animal you would expect to find between 50 mya and 46 mya.

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

Ambulocetus Carl Buell

What is the closest land dwelling relative of whales?

Whale Phylogeny, 1994 Hans Thewissen

Perissodactyls Odd-Toed Ungulates Rhinos & Tapirs Horses & Zebras

Artiodactyls Even-Toed Ungulates

But WHICH Hooved animals? Is there a way to demonstrate relatedness between hoofed animals and whales? 40-48: DNA analysis indicates hippos are the most closely related living animals to whales.

DNA Analysis Compare segments of beta-casein gene

DNA Differences

Whale’s Closest Land Dwelling Cousin: Hippos

FAREWHALE!