Fossils and Fossilization

Flashcards covering key vocabulary terms and definitions from the lecture on fossils and fossilization.

Fossils

Remains, traces, or imprints of once-living organisms preserved in the Earth's crust from past geologic or prehistoric times.

Body fossil

The actual remains of an organism, such as bones, teeth, shells, etc.

Trace fossil

An indication of organic activity, such as burrows, trails, nests, etc.

Permineralization

The deposition of minerals in the interstices of a skeleton without altering the original material.

Unaltered remains

The hard skeleton or soft parts of an organism that remain unchanged.

Altered remains

Fossils in which the soft parts decay, and the hard skeletons undergo alteration.

Carbonization

The removal of volatile compounds from an organism's remains, leaving mostly carbon in the form of a thin film.

Recrystallization

The alteration of less stable inorganic compounds into more stable ones without a chemical change.

Replacement

The process where original minerals of a skeleton are dissolved and replaced by other materials like silica or pyrite.

Fossilization

A random process that often leaves gaps in the documentation of evolutionary history.

Conditions favoring fossil preservation

Species with hard parts and quick burial have a better chance of fossilization.

Mould

The impression of skeletal remains left on rocks.

Cast

A physical replica of the original organism formed when a mold is filled with sediment or minerals.

Mass extinction

Periods in Earth's history when extinction rates greatly accelerated, sharply reducing biodiversity.

Biostratigraphy

The use of fossils to construct the geologic time scale based on the Principle of Biologic Succession.

Paleo-Environmental Analysis

The study of fossils to determine ancient climates, ecologies, and environments.

Linnaean taxonomy

A hierarchical system for classifying and naming living organisms proposed by Carl von Linnaeus.

Prokaryotes

The simplest life forms with genetic material not enclosed in a nucleus; includes bacteria.

Eukaryotes

Organisms with genetic material contained within a nuclear membrane; includes animals, plants, fungi.

Three Domain Paradigm

A classification system proposed by Carl Woese that divides life into Bacteria, Archaea, and Eukarya.

Extinction

The rule in the history of life indicating that 99% of all species that existed are now extinct.