Eocene

Andrewsarchus

When: Eocene
(37–34 mya)
Where: Asia
What: Mammal
Weight: 1 metric ton
Length: 3.5 meters
Diet: Carnivorous
Discovered: 1924

Arsinoitherium

When: Eocene to Oligocene
(36–30 mya)
Where: Africa
What: Mammal
Weight: 2–3 metric tons
Length: 3 meters
Diet: Herbivorous
Discovered: 1902

Basilosaurus

When: Eocene
(41–34 mya)
Where: North America, Africa
What: Cetacean Mammal
Weight: 15–20 metric tons
Length: 15–20 meters
Diet: Carnivorous
Discovered: 1834

Hyaenodon

When: Eocene to Miocene
(42–16 mya)
Where: North America, Europe, Asia
What: Mammal
Weight: 500 kg
Length: 2.5 meters
Diet: Carnivorous
Discovered: 1869

Perucetus

When: Eocene
(37–34 mya)
Where: South America
What: Cetacean Mammal
Weight: 200 metric tons
Length: 17–20 meters
Diet: Carnivorous
Discovered: 2023

Uintatherium

When: Paleocene to Eocene
(56–37 mya)
Where: North America
What: Mammal
Weight: 2 metric tons
Length: 4 meters
Diet: Herbivorous
Discovered: 1872