CHAPTER 20 VOCAB

HALF-LIFE

• Definition: The time required for half of the radioactive adams in a sample to decay.

EXTINCT

• Definition: Having no living members

RELATIVE DATING

• Definition: The science of determining The relative order of past events without necessarily determining their absolute age

RADIOMETRIC DATING

• Definition: A method of dating geological specimens by determining The relative proportions of particular radioactive isotopes.

GEOLOGICAL TIME SCALE

• Definition: A timeline of earths history

ERAS

• Definition: A long distant period of history with a particular feature or characteristic

PERIOD

• Definition: a length of portion of time

PLATE TECTONICS

• Definition: The interaction of rigid lithospheric plates which move slowly the underlying mantle

MACROEVOLUTIONARY PATTERNS

• Definition: major transformation in anatomy, phylogeny, ecology, and behavior, which usually takes place in larger clades.

BACKGROUND EXTINCTION

• Definition: species become extinct when they fail to adapt to competition and changing environment

MASS EXTINCTION

• Definition: When something drastic happens and effects species on a global scale

GRADUALISM

• Definition: evolution
• Definition: gradual reformatted and some change

PUNCTUATED EQUILIBRIUM

• Definition: when equilibrium is interrupted by small period of geological rapid change

ADAPTIVE RADIATION

• Definition: Process where a single species evolve into several different species

CONVERGENT EVOLUTION

• Definition: the appearance of similar characteristics of unrelated organisms

COEVOLUTION

• Definition: process by which two species evolve in response to changes in each other every time

ENDOSYMBIOTIC THEORY

• Definition: Proposes that organelles were formed when different types of cells joined in a kind of merger