Test 1 Flashcards
What is microevolution
the change in the genetic characteristics (allele frequency) of a population over time
what is macroevolution
the evolution of larger taxonomic groups over long periods of time
who was Alfred Russell Wallace
the British guy who proposed that natural selection was the mechanism for evolution and proposed warning coloration
what are transitional features
features in species that link them to older species (like fins going to limbs) which help scientists identify how lineages worked
what are homologies
shared physiological traits and genetics such as structural similarities, developmental similarities, genetic similarities
what is fitness
the relative ability of an individual to produce offspring that will survive
what is artificial selection
breeding
who are rosemary and Peter grant
recorded beak size and shape and body size of finches in the Galapagos before and after drought –> determined heritability of certain trains, looked at natural selection
what is a genome
a set of all genetic information (DNA) in a population
what is adaptation
evolving of a whole population to do better in an environment
what is acclimation
change on an individual level, usually not passed one
is evolution goal oriented
…no
whats phenotype
physical characteristics
whats genotype
genetic characteristics (AABb etc)
what are alleles
variants of a gene
whats diploid
you get one copy of a gene (allele) from mom and one from dad
whats a benefit to being diploid
if one gene fails you have another
what are the 4 ways natural selection can change a population
directional, stabilizing, disruptive, balancing
whats directional natural selection
changes the average value of a trait (beak size increasing)
whats a histogram
a graph where data points are grouped by value and shown as bars
whats stabilizing NS
reduces the amount of variation (skinner bell)
whats disruptive NS
increases the amount of variation
whats balancing NS
where no allele has an advantage so they balance out
whats sexual selection
where individuals have differing abilities to attract mates and mate
what are the two types of sexual selection
male-male competition, female choice
whats genetic drift
random effects (bug being stepped on, natural disaster, randomness of reproduction) that cause changes in the genome but not adaptation
does genetic drift increase or decrease genetic variation
decrease
does genetic drift increase or decrease genetic differences between populations
increases
whats gene flow
when individuals move between populations and interbreed
does gene flow increase or decrease genetic variation
increases
does gene flow increase or decrease genetic differences between populations
decreases (homogenizes populations)
do mutations increase or decrease genetic diversity
increase
why do mutations show up so much in bacteria populations
horizontal gene flow
are mutations consequential for evolution
only if they provide a fitness advantage, which is rare
what is the Hardy-Weinberg equation for
determining the frequency of alleles in a population
in the hardy-weinberg equation, what does p stand for
the frequency of the dominant allele
in the hardy-weinberg equation, what does p2 stand for
the portion of the population with the homozygous dominant genotype
in the hardy-weinberg equation, what does q stand for
the frequency of the recessive allele
in the hardy-weinberg equation, what does q2 stand for
the portion of the population with the homozygous recessive genotype
in the hardy-weinberg equation, what does 2pq stand for
the portion of the population with the heterozygous genotype
does inbreeding increase or decrease the frequency of heterozygotes
decreases
whats a biological species
members have the potential to interbreed in nature and produce fertile offspring
whats a morphospecies
members share morphological features (physical traits that are distinguishable)
whats a phylogenetic species
members share an ancestor and can be distinguished from other sets
what are the two major groups of reproductive barriers
prezygotic and postzygotic barriers
name the 5 types of prezygotic reproductive barriers
habitat isolation (deep water fish vs shallow), temporal isolation (mating occurs at different times), behavioral isolation (different mating dances), mechanical isolation (mating physically doesnt work), gametic isolation (gametes fail to attract each other or are inviable (sperm cant get to egg))
name the 3 types of post zygotic reproductive barriers
reduced hybrid viability (offspring die), reduced hybrid fertility (offspring can’t mate), hybrid breakdown (offspring of offspring aren’t fertile or viable)
whats allopatric speciation by dispersal
dispersal and colonization (some leave the population and go somewhere else and start a new population), then genetic drift and selection cause the two populations to be isolated
whats allopatric speciation by vicariance
chance separation (flood, fire, road, etc), then genetic drift and selection, so two populations are isolated
whats adaptive radiation and what kind of geography is it common in
basically a species boom, when there’s rapid evolution that causes speciation as species occupy new niches, common on island chains
whats sympatric speciation
no separation of the population, just genetic drift and selection within the population that separates it into two (such as mating times separating) `
whats homoploid hybridization
speciation due to differing traits in hybrid offspring (hybrids become their own species)
whats convergent evolution
when the same adaptive radiation offers in different places (the same species evolve independently from each other)
what is species richness
the number of species there are
what is biodiversity/species diversity
the number of species and their relative abundance
whats the benchmark for a mass extinction
60% of species wiped out within 1 million years
how many mass extinctions have there been
5
whats an endemic species
confined to a single area
whats an autotroph
an organism that can feed itself (takes very simple nutrients like sunlight, CO2)
what type of producer are plants
primary producers (feed whole ecosystem)
what are the two types of plant parasites
obligate (have to be parasites) and facultative (are parasites only when necessary)
why are some plants carnivores
need more nitrogen
how do plants store food
in the form of starch
what are the cell walls of plants made of
cellulose
do plants reproduce sexually or asexually
both
