science notes

Fossil

The preserved remains or traces of a once living organism.

Body Fossils

Fossils formed when the bodies or body parts of organisms are preserved.

Trace Fossils

Fossils that preserve traces left by living things, such as footprints or feces.

Mold Fossil

A type of fossil produced when an organism's body leaves an imprint in sediment.

Cast Fossil

A fossil that has the same shape as the original organism, formed when a mold is filled with a different material.

Amber

A material formed from hardened resin that can preserve entire organisms in incredible detail.

Absolute Dating

A method used to determine the exact age of a fossil.

Relative Dating

A method used to determine the age of a fossil based on its position in rock layers.

Biodiversity

The variety of species on Earth.

Adaptive Radiation

A rapid increase in biodiversity where new species are well suited to their environment.

Cambrian Explosion

An adaptive radiation that occurred during the Cambrian Period, leading to the origin of most major animal groups.

Extinction

The process by which a species ceases to exist.

Mass Extinction

A significant event in Earth’s history where a large number of species die out in a relatively short time period.

Pakicetus

The oldest known fossil whale relative, resembling a wolf and lived mainly on land.

Ambulocetus

Known as the 'walking whale', it had legs adapted for both walking and swimming.

Archaeopteryx

An important fossil that shows features of both birds and dinosaurs, often referred to as the first bird.

Dromaeosaurs

A group of theropod dinosaurs closely related to Archaeopteryx, characterized by certain features such as teeth and claws.