Historical Geology - Early Mesozoic

A set of vocabulary flashcards covering key concepts and terms related to the Early Mesozoic period in historical geology.

Mass Extinction

A period in which a large number of species vanish from Earth.

Triassic

The first period in the Mesozoic era, known for the evolution of early dinosaurs and mammals.

Jurassic

The second period of the Mesozoic era that saw the dominance of dinosaurs and the first appearance of birds.

Ammonoids

A subclass of mollusks that are important guide fossils and characterized by their coiled shells.

Dinosaurs

A diverse group of reptiles that dominated terrestrial ecosystems during the Mesozoic era.

Plesiosaurs

Marine reptiles that evolved from nothosaurs and had long necks and small heads.

Ichthyosaurs

A group of marine reptiles resembling modern dolphins, which gave birth to live young.

Gymnosperms

Non-flowering seed plants that dominated the terrestrial flora in the early Mesozoic.

Tethys Seaway

An ancient ocean that separated the landmasses of Laurasia and Gondwana during the Mesozoic.

Rifting

The process by which Earth's crust breaks apart, leading to the formation of new ocean basins.

Pterosaurs

Flying reptiles that lived during the Mesozoic, characterized by their long wings and hollow bones.

Cycads

A group of seed plants with a long fossil history, common in Mesozoic ecosystems.

Therapsids

A group of synapsid reptiles that were ancestors to mammals and existed prior to the rise of dinosaurs.

Thecodonts

Early archosaurs that are considered ancestors to crocodiles and dinosaurs.

Sauropods

Large, long-necked dinosaurs that were primarily herbivorous and included some of the biggest animals to ever live.

Morrison Formation

A geological formation known for its rich fossil beds of Jurassic vertebrates, especially dinosaurs.