Dev - xLecture 13B: Paleozoic Life

Eurypterids

Eurypterids

Top predators of the Silurian, also known as sea scorpions.

Age of the Fish

A period during the Devonian when fish were abundant and diversifying.

Jawless Fish

Early fish known for their lack of jaws, existing from the Late Cambrian to Ordovician.

Acanthodians

Small fish that became popular in the Devonian, characterized by large spines and jaws.

First True Shark

The initial ancestors of modern sharks, likely evolved from Devonian acanthodians.

Placoderms

One of the first jawed fishes, heavily armored, and prominent in the Silurian and Devonian.

Dunkleosteus

The largest predator of the Devonian seas, known for its heavily armored head and razor sharp teeth.

Ray-Fin Fish

A type of bony fish lacking muscular bases to their paired fins, which evolved in the Late Devonian.

Lobe-Fin Fish

Fish with muscular fins that are homologous to human arm bones, known for their adaptation to land.

Nautiloids

Cephalopods with straight or curved shells, top predators of the Ordovician.

Ammonoids

Cephalopods from the Devonian with coiled shells and complex suture patterns.

Silurian Land Plants

The first land colonizers, primarily microbiotic crusts that eventually led to more complex plant life.

Devonian Land Plants

Marked by the evolution of complex vascular systems and roots, leading to taller plant species like lycopsids.

Fusilinids

Index fossil for marine rocks of the Pennsylvanian-Permian period, consisting of tightly packed, secreted calcite.

Amniotes

Tetrapods capable of reproducing on land due to their eggs that do not require water.

Pelycosaurs

Primitive synapsids from the Permian, known for their finbacks.

The Great Dying

The Permian-Triassic mass extinction event, leading to a significant loss of biodiversity.

Tiktaalik

A transitional fossil showing features of both fish and early tetrapods.

Global Cooling Event

A likely cause of the Devonian extinction, impacting marine biodiversity significantly.

Disjunct Flora and Fauna

Species that are related but geographically separated due to environmental changes.

Tethys Sea

A warm equatorial sea that formed when Pangea was established, known for high biodiversity.

Carboniferous Amniote Egg

An egg type that allowed tetrapods to reproduce away from water, crucial for terrestrial life.