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50 Cards in this Set

  • Front
  • Back
the study of patterns in the distribution of species
Cuvier hypothesized that evolutionary changes were from periodic natural disasters, called revolutions
Jean Lamarck
proposed "inheritance of acquired characteristics"-- evironmental pressures along with internal needs made changes in evolution. the giraffe thing, he was wrong about that.
came up with Natural selection, influenced by his studies on the Beagle voyage, and influenced by Lyell
Natural Selection
individuals with certain inhereted traits survive longer and produce more offspring, and these individuals are best suited for the environment at that time
Non random mating
occurs when an individual CHOOSES a mate
sexual selection
based on any trait that gives an organsim a preferred advantage in mating and producing offspring
geographic variation
differences between organisms occupying different areas. See: Cline
a graded series of changes in some characteristics of a species, coorelated with some gradual change in an environmental factor across the geographic range. ex: ear length in wolves.
a species that occupies many different environments and appears different in each-- polymorphic (many forms)
changes that are larger, may result in the formation of a new species
process by which new species form
group of potentially interbreeding natural populations which are reproductively isolated from other such groups
pop.s that are geographically isolated
pop.s that lie adjacent but never interbreed
no geographical isolation overlapping
reproductive isolation
any aspect of structure or functioning that prevents successful interbreeding
prevents a zygote from forming
temporal barrier
closely related species reproduce at different times, live in different habitats
behavioral isolation
no sexual attraction between individuals that lack proper behavior
mechanical isolation
the genitalia dont fit
egg and sperm have no recognition
post zygotic mechanism
prevent development of fertile adults
hybrid inviability
doesnt survive
hybrid sterility
survives but is sterile
divergent evolution
2 or more species evolve from a common anscestor, and become progressively different thru time
adaptive radiation
(rapid divergent evolution)
rapid evolutionary activity by which relatively primtive, unspecialized species produce many highly specialized species that exploit a variety of habitats
convergent evolution
organisms that occupy similar environments often appear similar due to environmental pressures even though they are not closely related
parallel evolution
when 2 or more species evolve from a commmon ancestor but remain somewhat similar thru time
co evolution
species evolve in such a way that changes in one cause reciprocal changes in the other
rate of evolution: Gradualism
evolution proceeds at a slow and steadt reate
punctuated equillibrium
1970s-- eldridge and gould
death of a species. happens when last individual dies
background extinction
a steady rate of species turnover-- that occurs in lineages thru time. loss-- 180-300 species lost each million years. new species evolved replacing a lot of them
mass extinction
abrupt increase in extinction rate, occurs over a short period of time. 5 major ones have occured
possible cause of M.e
earth struck by asteroid (found abundance of irridium)
habitat destruction
introduction of nonnative species. --intro of dangerous substances.
--over exploitation (too much hunting, etc)
Origin of Life
13.8 billion years ago--
Big Bang formed universe
the sun
came 9 billion years ago
the earth fomred
4.6 billion years ago
original source of alleles
gene flow
preserves species cohesion
genetic drift
erodes species cohesion
microevolutionary processes
(mutation, gene flow, genetic drift, nat. selec) stability or change is the outcome, influence by pop. size and enviro. conditions
genetic persistance
(macro) basis of unity of life. biochemical and molecular basis of inheritance extends from the first cells through all line of descent
genectice divergence
(macro) basis of life diversity, brought on by adaptive shifts, branching, radiation, rates vary within and between lineages
genetice disconnect
(macro)end of the line for species, mass extiction is an example
morphological divergence
change of body form from a common anscetor
homologous structure
similarities in body parts, suggesting inheritance
morph. convergence
dissimilar body parts evolved in similar ways in evolutionarily distant lineage
analogus structures
structure that are similar but have adapted independently