Chapter 14 How Biological Diversity Evolves

the major changes in the history of life
formation of new species
Biological Species Concept
a species concept defining a species as a population or group thereof whose members potentially interbreed and with one another in nature to produce
group of similar organisms that can breed and produce fertile offspring
Prezygotic Barriers
these prevent mating or fertilization between species
Postzygotic Barriers
mechanisms that operate should interspecies mating actually occurs and form hybrid zygotes
Allopatric Speciation
the initial block to gene flow is a geographic barrier that physically isolates the splinter population
Sympatric Speciation
the orgin of new species without geographic isolation
Punctuated Equilibrium
this addresses the nongradual appearance of species
a structure that evolves in one context and later becomes adapted for other functions
the retention into adulthood of features that were solely juvenile in its ancestors
Geologic Time Scale
this reflects a consistent sequence of geolic periods
Radiometric Dating
based on the decay of radioactive isotopes
the study of diversity and relationships or organisms, both past and present
the identification, naming and classification of species
consisting of two names or terms
this is the first part of the binomial that which the species belong
this places similar genera in the same family, puts families in orders, orders into classes, classes into phyla, phyla into kingdoms and kingdoms into domains
the evolutionary history of a species
Phylogenetic Tree
the principle of common descent is reflected in the branches of the tree
Convergent Evolution
species from different evolutionary branches may have certain structures that are superficially similar if natural selection has shaped analogous adaptations
the scientific search for clades
consists of an ancestral species and all its descendants a distinctive branch in the tree of life