Evolution Flashcards
change in the genetic makeup of a population with time
evolution
discredited theory that said the new organs or changes occurred because of the needs of an organism (based on the use or disuse of an organ)
Lamarckian evolution
Lamarckian evolution: any useful characteristic – in one generation was transmitted to the next generation
acquired
Only – of sex cells and not acquired characteristics can be inherited
DNA
changes acquired during an individual’s life are changes in the – cells
somatic
ability to survive and reproduce
fitness
environmental pressures – for the organism most fit to survive and reproduce
select
more offspring are produced than can survive (insufficient resources to support entire population)
overpopulation
offspring naturally show differences or – in their characteristics compared to those of their parents
variations
Hugo de Vries suggest that – are the cause of variations
mutations
the developing population must – for the necessities of life
compete
due to competition, many young must die and the number of adults in the population generally remains – from generation to generation
constant
over many generations of natural selection, the favorable changes called – are perpetuated in the species
adaptations
accumulation of adaptations eventually results in such significant changes in the gene pool that a new species has –
evolved
evolution of new species
speciation
species are groups of individuals that can – freely with each other but not with members of other species
interbreed
small local populations that form within a species
deme
If demes become – speciation may occur
isolated
genetic and eventually reproductive isolation often results from the – isolation of a population
geographic
when two species from different ancestors develop similar traits
convergent evolution
independent evolution of similar traits starting from a similar common ancestor
parallel evolution
species with a shared common ancestor develop differing traits due to their differing environments
divergent evolution
emergence of a number of lineages from a single ancestral species
adaptive radiation
distinct lifestyle
niche
includes all members of a particular species inhabiting a given location
population
a population’s gene pool is the sum total of all the – for any given trait in a population
alleles
relative frequency of a particular allele
gene frequency
evolution can be viewed as a result of changing – within a population
gene frequencies
Hardy-Weinberg conditions
large population
random mating
no mutation, migration, natural selection (genes are equally successful at reproducing)
real populations have – gene pools and migrating populations
unstable
agents of microevolutionary change include natural selection, mutation, – mating, genetic drift, and gene flow
assortive
the frequency of favorable genes – within a gene pool
increases
gene mutations change– in a population, shift gene equilibria by introducing additional alleles
allele frequencies
mates are usually selected to criteria such as phenotype and –
proximity
changes in gene pool due to chance
genetic drift
genetic drift is more pronounced in small populations, where it can be called –
founder effect
migration of individuals between populations will result in a loss or gain of genes –> change gene pool
gene flow
fossils are – evidence of evolutionary change
direct
fossils are generally found in – rocks
sedimentary
fossil resin of trees
amber
process by which minerals replace the cells of an organism
petrification
impressions left by an organism (footprints)
imprints
form hollow spaces in rocks as the organism within decay
molds
formed by minerals deposited in molds
casts
primitive arthropod (similar to crabs) which dominated the early Paleozoic era
trilobite
dinosaurs related to reptiles and birds that dominated the –era
Mesozoic era
dawn horse the size of a fox that ate soft leaves
Eohippus
hairy elephants found in Siberian ice
woolly mammoth
Saber-tooth tigers preserved in –
asphalt tar pits
Archaeopteryx link with reptiles (teeth and scales) and birds (–)
feathers
same basic anatomical features and evolutionary origins but may have different functions
homologous structures
similar functions but may have different evolutionary origins and entirely different patterns of development
analogus structures
Similar – development is evidence of evolution from common ancestors
embryos
chemical similarity of – of different organisms very closely parallels the evolutionary pattern
blood
Miller: UV radiation + heat + mixture of methane, hydrogen, ammonia and – result in organic compounds
water
colloidal protein molecules tend to clump together to form – a cluster of colloidal molecules surrounded by a shell of water
coacervate droplets
a small percentage of coacervate droplets possessing favorable, stable characteristics may have eventually developed into the first –
primitive cells
first primitive cells probably possess – and became capable of reproduction
nucleic acid polymers
produce organic compounds from substances in their surroundings
autotrophs
the addition of – to the atmosphere converted the atmosphere from a reducing to an oxidizing one
reducing
some molecular oxygen was converted to – which blocks high-energy radiation
ozone
chemosynthetic bacteria
autotrophic anaerobes
green plants and photoplankton
autotrophic aerobes
