Sea Turtle Evolution

Eunotosaurus Africanus

- Greek for "Original Noded Lizard"

- Late Permian (Around 260-255 MYA)

-A possible omnivorous

Appearance/Environment

Lived in Southern Africa

• One foot long

• Weighed a few pounds

• Had nine elongated trunk vertebrae

• Had nine pairs of broad T-shaped dorsal ribs

Adaptations/Evolution

Broad-Ribbed Structures

• Provided stability and leverage for burrowing

• Ribs formed to decrease consumption

• Broad ribs able to make contact with each other which is a feature of common day turtles

• Wide ribs and distinctively circular torso represent those of present day turtles

Appearance

Environment

A water dweller

Broad dorsal ribs, complete plastron, partial shell

Odontochelys Fossils & Bone Structures

Adaptations

Evidence for Evolution

Developed underside shell to protect them

Developed shell to protect underside just like present day sea turtles

Proganochelys Quenstedti

-Proganochelys (Early shell)

-Late Triassic (210 MYA)

-100 cm in length

-Primitive stem-turtle

- Often are associated with Germany

Appearance / Environment

Some known locations are Germany‭ ,Greenland‭, and Thailand‭

-Tall and wide skull

-Dermal ossicles covered by thick scales

-Tail with a small club at the end

Adaptations / Evolution

Neck was covered with spines to protect itself from predators.

Head could not retract into its shell like present day sea turtles.

Appearance/ Environment

Appearance / Environment

2 meters long

Similar characteristic to modern day sea turtles

Discovered in Colombia

Lived in warm climate with high sea levels

Adaptations/ Evolution

Similar characteristics to present day turtles such as it long flipper to help it swim fast and escape predators.

Adaptations / Evolution

Possibly have evolved to be a sea dweller and then other turtles may have late evolved similarly from a different ancestor.

Sea Turtle

Appearance

Adaptation

Non-retractable neck to swim faster to escape predators.

31-47 inches long with paddle like flippers and a top and bottom shell.

Environment

Evolution?

Shallow seagrass beds of the Indian Ocean, reefs, and Eastern Pacific beaches.

Green sea turtles are an endangered species due to pollution, illegal trade, consumption, etc.

Timeline

Proganochelys Quenstedti (210 MYA)

Chelonia Mydas

(Present Day)

Eunotosaurus Africanus (260 MYA)

251- 201 MYA

145- 66 MYA

Cretaceous

Permian

Triassic

Jurassic

Cenozoic

298- 251 MYA

66- 0 MYA

201- 145 MYA

Present Day

Odontochelys Semitestacea (220 MYA)

Desmatochelys Padillai (120 MYA)

Sources

• https://www.thoughtco.com/prehistoric-turtles-story-of-turtle-evolution-1093303

I trusted this resource for information because it provided easy access to the authors background work information. It was also recently updated on January 12, 2019. It had an informative and slightly serious tone.

• https://myfwc.com/research/wildlife/sea-turtles/florida/life-history/

I trusted this resource for information because it gave very informative descriptions. It is also and organization based website on wildlife conservation.

• https://www.seaturtle-world.com/sea-turtle-evolution/

I trusted this resource for information because it was a very informational and neutral toned article. It had also been published on January 4, 2014.