Field Museum

Silurian Cephalopods possessed long, hard, segmented shells like the one shown in this fossil. They also possessed soft bodies with tentacles. These softer parts of their bodies were seldom, if not never, been preserved in fossils.

Fossil Formation

Image of a skin impression fossil from the dinosaur Edmontosaurus.

Fossil Excavation

Observe these silurian creatures' fossils and the ways artists have imagined them. What do you notice about the animal structures pictured in these fossil images and their artist renderings? Are these fossils of complete organisms, or partial organisms? How do you think scientists and artists are able to reconstruct what an organism looked like when only partial fossil evidence is available?

Silurian Fossils and Artists Illustrations

The rock cycle illustrates the relationship between different types of rocks. Igneous or sedimentary rocks can turn into metamorphic rocks when heat and pressure are applied to these rocks. Igneous rocks are formed when melted rock cools. Sedimentary rock forms when small deposits of rock or bone are compacted into one mass, usually in underwater conditions.  

Rock Layers

In the last activity, you learned about cast, mold, trace and imprint fossils. Use this annotation activity to draw a diagram or graphic organizer explaining what you know about these different types of fossils and how they form. 

Draw Fossil Types

Learn about how paleontologists excavate, preserve, and use fossils to study Earth's past life!

All About Fossils

cnidarian1.jpg

Rugose corals are extinct, but they are related to modern corals, which live only in seawater. The animal within rugose corals resembled a modern sea anemone and captured small animals and other food particles with a ring of tentacles surrounding a mouth. Rugose corals included both solitary forms, where the coral animal was housed in a cup-shaped skeleton, and colonial forms, where many coral animals lived together in individual spaces within the skeleton

Cnidarian - Cyathaxonia wisconsinensis

Description

Object Information

Appears In

All About Fossils