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22 Cards in this Set

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adjective. Refers to an organism that has inherited characteristics that make it suited to its environment. Often used to describe a specific characteristic, such as a polar bear's white fur.
Adaptive characteristics
Inherited characteristics that have evolved in a population because they give the individuals a survival advantage. The long neck of the giraffe is an example.
Adaptive value
The extent to which a particular inherited trait makes an organism more suited to its environment. Can be high or low.
Refers to a characteristic that increases an individual's chances of surviving in a given environment.
Biological evolution
Basically, the theory that present days species developed from earlier, very different species over the course of earth's history.
The struggle between two or more individuals for the same limited resource or resources. Can occur within a population or between two or more different populations.
Dichotomous key
A guide for identifying or organizing a things. An initial group is split into 2 new groups based on some characteristic that distinguishes them. For example, in a group of students we might split into a male and female grouping. The each group could then be split again based on height, for example. And so on.
Over many generations the characteristics of a population change. Many species that existed in the past but are now extinct actually developed into species that exist today.
Evolutionary change
The change in the genetic make-up of a population that occurs over generations. May result from natural selection, random genetic drift, etc.
The disappearance forever of a species or population. A species may simply die (an evolutionary "dead end") out or it may evolve into other species
Fossil record
The story told in the preserved remains of extinct or ancient organisms, usually found in geological formations.
Geological time
Relatively long periods of time in Earth's history in which geological events (mountain formation, for example) and evolution unfold.
Mechanism of evolution
Any explanation of HOW species or populations change over time. Natural selection, sexual selection, random genetic drift, etc. are examples.
Natural selection
One of the mechanisms by which evolution can occur. 1) The inherited characteristics possessed by some members of a population, 2) give them a survival advantage over other individuals, 3) leading to greater reproductive success and, 4) causing their favorable characteristics to spread through the population. Sometimes summarized as "survival of the fittest" but make sure you understand what "fit" means.
Overproduction of offspring
One of the basic laws of natural selection, it states that each generation produces far more offspring than can possibly survive.
Reproductive success
A measure of how many offspring a particular individual produces. Individuals having favorable heritable characteristics are more likely to have more offspring, and their favorable genes will then become more common in a population.
In general, the act of choosing one or more individuals over other individuals. In evolution, it refers to environmental factors (resources, predators, prey, etc.) that "choose" or determine which individuals are more likely to survive.
Selective breeding
AKA artificial selection. The human act of choosing the offspring of domesticated animals or crops that have some desirable trait and the mating the offspring in such a way as to maintain that desirable trait.
A group of individuals that generally only interbreed with other members of the same group due to physical, behavioral, or geographical differences
Struggle for survival
The effort individuals exert to stay alive in the face of limited resources, disease, and predators.
The act of staying alive
Variations among offspring
The differences that exist among the offspring of individuals that make them different from each other and their parents. This is the raw material that natural selection acts on.