Chapter 7 & 8 Flashcards
Species
A group of organisms that are closely related and can mate and produce fertile offspring.
Adaptation
A characteristic that improves an individual’s ability to survive and reproduce in a particular environment
Evolution
The process in which inherited characteristics within a population change over generations such that new species sometimes arise.
Fossil
The trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock
Fossil Record
A historical sequence of life indicated by fossils found in layers of Earth’s crust
Trait
A genetically determined characteristic
Selective Breeding
The human practice of breeding animals or plants that have certain desired traits
Natural Selection
The process by which individuals that are better adapted to their environment survive and reproduce more successfully than less well adapted individuals do; a theory to explain the mechanism of evolution.
Generation Time
The period between the birth of one generation and the birth of the next generation
Speciation
The formation of new species as a result of evolution
Relative Dating
Any method of determining whether an event or object is older or younger than other events or objects.
Absolute Dating
Any method of measuring the age of an object or event in years.
Geologic Time Scale
The standard method used to divide the Earth’s long natural history into manageable parts
Extinct
Describes a species that has died out completely
Plate Tectonics
The theory that explains how large pieces of the Earth’s outermost layer, called tectonic plates, move and change shape
Precambrian Time
The period in the geologic time scale from the formation of the Earth to beginning of the Paleozoic era, from about 4.6 billion to 542 million years ago.
Paleozoic Era
The geologic era that followed Precambrian time and that lasted from 542 million to 251 million years ago.
Mesozoic Era
The geologic era that lasted from 251 million to 65.5 million years ago; also called Age of Reptiles
Cenozoic Era
The most recent geologic era; beginning 65 million years ago; also called Age of Mammels
Primate
A type of mammal characterized by opposable thumbs and binocular vision
Hominid
A type of primate characterized by bipedalism, relatively long lower limbs, and lack of tail