Unit 7 ADV BIO Fossil Record Review

Extinct

when the entire species has died out

Paleontologist

a scientist who studies fossils, which are the remains of ancient plants and animals that have been preserved in rock

Relative dating

a method of determining the age of a fossil, rock, or other geological feature by comparing its position in the Earth's geologic layers to the positions of other materials

Adaptive radiation

the process by which a single species diversifies and evolves into multiple different species, each adapted to a different ecological niche or habitat. (Darwin’s finches)

coevolution

the process by which two or more species evolve in response to each other's adaptations over a period of time

Micro Fossils

tiny fossilized remains of microscopic organisms, such as bacteria, algae, fungi, and protists

Eras

large spans of time that are used to divide Earth's history based on major geological and biological events

the process in which different organisms independently evolve similar traits or characteristics in response to similar environmental pressures, despite not sharing a recent common ancestor

convergent evolution

Fossil Record

is the collection of physical evidence, such as fossils and other remnants of organisms, that have been preserved over time and provide information about the history of life on Earth

coevolution

the process by which two or more species evolve in response to each other's adaptations over a period of time

Mass Extinction

when many types of living things go extinct at the same time

Macroevolution

refers to large-scale evolutionary patterns and processes that occur over long periods of time

Radioactive dating

a method used to determine the age of rocks, fossils, and other geological materials based on the decay of radioactive isotopes

Half-life

length of time required for half of the radioactive atoms in a sample to decay

Endosymbiotic theory

theory that proposes that eukaryotic cells evolved from the symbiotic relationship between two different types of prokaryotic cells

punctuated equilibrium

a theory in evolutionary biology that suggests that species tend to experience relatively long periods of little or no evolutionary change (equilibrium), which are punctuated by shorter periods of rapid and dramatic evolution (punctuation)

Index Fossils

fossils of organisms that lived during a specific period of time and are used by scientists to date the rock layers or sedimentary deposits in which they are found ; are typically organisms that lived for a relatively short period of time, were abundant and widespread, and had distinct physical characteristics that make them easy to identify

Law of Superposition

states that in a sequence of undisturbed rock layers, the oldest layer is at the bottom and the youngest layer is at the top

Proteinoid Microspheres

tiny, bubbles made up of protein molecules that can form spontaneously under certain conditions

Geologic time-scale

a system of chronological dating that divides the Earth's history into different time periods based on major geological and biological events

Periods

subdivisions of geologic eras that represent shorter spans of time within the overall history of Earth