genetically coded traits that occur in organisms and enable them to be more successful in their environment
a mechanism that explains changes in a population that occur when organisms with
favorable variations for that particular environment survive, reproduce, and pass these
variations on to the ne xt generation.
is geographically separated from one another.There is no interbreeding between organisms of the same species
includes the variety of habitats, living communities,
and ecological processes in the living world.
includes the vast number of different organisms on Earth
refers to the sum total of all the different forms of genetic information carried by all living organisms on Earth. It gives rise to inheritable variation, which scientists believe provides the raw material for
the evolution of a new species that occurs due to changes in gene flow in populations of the ancestral species.
occurs when physical barriers cause populations to divide and prevent mating of individuals.
is evolution that occurs over a long period of time when adaptive changes accumulate slowly and steadily over time in a population. Darwin believed in this.
states that speciation occurs quickly in rapid bursts, with long periods of stability.
used to determine the relative ages of fossils within a time period. These isotopes act as clocks for measuring time. To use this method,
scientists must know:
1. the half- life of the isotope being measured
2. how much of the isotope was originally present in the fossil or in the
rock containing the fossil
3. how much of the isotope is left
By matching rock layers with fossils, geologists
can determine the age of the rocks, while paleontologists can determine the age of the
the permanent loss of a species
is when species diversity occurs in a relatively short time. It occurs when a population colonizes a new area
This is where unrelated species may
independently evolve superficial similarities because of their adaptations to similar
the variety of organisms, their genetic information, and the communities in which they live.
the relative reproductive efficiency of various
individuals or genotypes in a population. it depends on the probability that the one individual will both survive and reproduce successfully