Dinosauria 17

Dinosaurs proper, including the birds that survived them.

Theropoda 9 Bipedal, mostly carnivorous, hollow-boned.

Sauropodomorpha 3 Long-necked, small-headed, graviportal.

Ornithischia 5 Bird-hipped plant eaters: plated, armoured, horned, beaked.

Reptiles (non-dinosaur) 4

Animals routinely filed next to dinosaurs and just as routinely mislabelled as one.

Pterosauria 1 Flying archosaurs with a membrane wing on one finger.

Mosasauridae 1 Open-ocean squamates with a flipper-paddled tail.

Plesiosauria 1 Four-paddle swimmers with a rigid trunk.

Ichthyosauria 1 Dolphin-shaped, live-bearing, ringed vertebrae.

Synapsida & mammals 2

The line that led to us. The sail-backs are in here, not with the dinosaurs.

Sphenacodontidae 1 Permian predators with a neural-spine sail.

Cetacea 0 Fully aquatic mammals with hind limbs reduced to vestiges.

Proboscidea 1 Elephants and their extinct kin; tusks are modified incisors.

Carnivora 0 Shearing carnassial teeth, four or five toes, no hooves.

Invertebrates 3

Everything with an exoskeleton or no skeleton at all. Most of the fossil record by count.

Radiodonta 1 Stem arthropods with a ring of toothed grasping appendages.

Lobopodia 0 Soft-bodied panarthropods walking on stubby unjointed legs.

Trilobita 1 Calcite eyes, a three-lobed axis, and moult halves everywhere.

Insecta 1 Six legs, two wing pairs, tracheal respiration.

Bonebed › Period index

Jurassic

201 to 145 Ma

Pangaea breaks apart, shallow seas flood the continents, and sauropods reach their absolute size ceiling. The Solnhofen lagoon preserves feathers in limestone.

8 entries in this period