Biology Test -- Evolution
Terms
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- biogeography
- the study of patterns in the distribution of species
- catostrophism
- 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.
- Darwin
- 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
- 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.
- Ecotype
- a species that occupies many different environments and appears different in each-- polymorphic (many forms)
- macroevolution
- changes that are larger, may result in the formation of a new species
- speciation
- process by which new species form
- species
- group of potentially interbreeding natural populations which are reproductively isolated from other such groups
- allopatric
- pop.s that are geographically isolated
- paratric
- pop.s that lie adjacent but never interbreed
- sympatric
- no geographical isolation overlapping
- reproductive isolation
- any aspect of structure or functioning that prevents successful interbreeding
- prezygotic
- 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
- gamete
- 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
- extinction
- 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
- mutation
-
original source of alleles
micro - gene flow
-
preserves species cohesion
micro - genetic drift
-
erodes species cohesion
micrio - 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