Definition
graptolite
noun
- An extinct marine animal from the Paleozoic Era, known from fossilized remains that resemble writing or marks on rock.
Usage: paleontology; geology
Examples
- Graptolites are important index fossils used by geologists to date rock layers.
- The name graptolite comes from Greek words meaning 'written stone' because of their appearance.
- Scientists study graptolite fossils to understand ancient ocean environments.
- Graptolites lived in colonies and floated in Paleozoic seas.
- The discovery of graptolite remains helped establish the geological timescale.