2. Hallucigenia Cambrian Period (~530-505 Ma)
Thought to be a worm, possibly an early ancestor of velvet worms
1-3 cm long
Found in Canada
and China

4. Jaekelopterus Devonian Period (~405 Ma)
The largest known species from a group of arthropods called “sea scorpions” or eurypterids
Up to 8 feet
long
Found in
Germany

6. Walliserops Devonian Period (~400-390 Ma)
A “trident” bearing trilobite
1-8 cm long
Found in Morocco

8. Tiktaalik Devonian Period (~375 Ma)
A lobe-finned fish which represents one of the oldest examples of fish developing adaptations to life on land
Its name was
suggested by
Inuit elders
3 to 9 feet long
Found in Nunavut,
Canada

10. Dunkleosteus Devonian Period (~380-360 Ma)
A carnivorous placoderm, or “armored” fish
Some species
grew up to 33
feet long!
Found in
North America,
Poland, Belgium
and Morocco

11. Angiosperm

12. Lepidodendron Devonian to Triassic Periods (~380-205 Ma)
Very common plants of the Carboniferous Period known as “scale trees”
Estimated to grow
taller than 100 feet
Had a nearly
worldwide
distribution

14. Arthropleura Mississippian to Permian Periods (~340-280 Ma)
A very large herbivorous millipede, which is the largest known
land invertebrate
ever!
1 to almost 9! feet
long
Found in North
America and Europe

16. Inostrancevia Permian Period (~260-254 Ma)
A large carnivorous synapsid or “mammal-like reptile” from the group called gorgonopsids
Up to 12 feet long
Found in Northern Russia

18. Archaeopteryx Jurassic Period (~151-148 Ma)
Well-known for being a transitional fossil between dinosaurs
and birds
Up to a 1.5 foot
wingspan
Found in Germany

20. Eomaia Cretaceous Period (~125 Ma)
An early mammal that is not truly a placental mammal, but one of the oldest ancestors to display traits of placentals
10 cm (4 inches) in length
Found in China

22. Spinosaurus Cretaceous Period (~112-97 Ma)
A piscivorous (fish-eating) theropod dinosaur
40 to 60 feet long
Found in Egypt and
possibly in
Morocco

24. Parapuzosia Cretaceous Period (~95-70 Ma)
A very large species of ammonite, related to animals such as squid and octopus
Up to 11 feet in
diameter
Found in North and
South America and
Europe

26. Prognathodon Cretaceous Period (~94-66 Ma)
A species of mosasaur, a type of marine reptile
Up to 30 feet long
Found nearly worldwide

28. Stygimoloch Cretaceous Period (~66 Ma)
A pachycephalosaurid dinosaur whose name translates to “demon dinosaur from the river Styx”
7 to 10 feet long
Found in
Montana and
Wyoming

30. Titanoboa Paleocene Epoch (~60-58 Ma)
The biggest known snake to ever live!
Up to 50 feet long
Found in Colombia

32. Teilhardina Eocene Epoch (~56-50 Ma)
The earliest known North American
primate
Less 1 foot long from head to tail
Known from Belgium, China, France,
and the United States

33. Amphicyon

34. Amphicyon Miocene Epoch (~18-2.5 Ma)
A carnivorous, bone-crushing mammal known popularly as a “bear-dog”
Up to 8 feet long
Found in North
America, Asia,
Africa, and
Europe

36. Platybelodon Miocene Epoch (~15-4 Ma)
A species of “shovel-tusker” (or gomphotheres) that is related to elephants
Up to 12 feet long
Found in Africa,
Europe, Asia,
and North America

38. Argentavis Miocene Epoch (~8-6 Ma)
One of the largest flying birds to ever live
The estimated wingspan is 23
feet…about twice as large as
the bird with the largest
wingspan today (the
wandering albatross)!!
Found in Argentina

40. Megatherium Pliocene to Holocene Epochs (~2 Ma- 10,000 yrs ago)
The largest known species of giant ground sloths
Up to 20 feet long!
Originally lived in South
America before emigrating
to North America during the
Great American Biological
Interchange