Fossils from the Eocene Pig-like Indohyus  “India’s pig” Size of raccoon or domestic cat Omnivorous Shares auditory bulla structure with extinct and living cetaceans

Thewissen et al. (2009)

Femur of Indohyus Marrow cavity only 42% of thickness of bone Other mammals usually 60% Termed osteosclerotic Thewissen et al. (2009)

Human femur

Pakicetus Fossils from the Eocene 3.3 to 6.6 feet in length Probably carnivorous Ate fish and small mammals Shares auditory bulla with extinct and living cetaceans Probably semiaquatic By Kevin Guertin from Ottawa, Ontario, Canada - DSCF1201, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=36657302

Thewissen et al. (2009)

Ambulocetus Fossils from the Eocene ~ 9.8 feet long Probably ambush predators Ate larger fish and aquatic tetrapods Probably fully aquatic Slow swimmer https://www.youtube.com/watch?v=8cn0kf8mhS4

Ambulocetus Fossils found in probable estuarine sediments

Thewissen et al. (2009)