Evolutionary genetics Flashcards
the theory of descent with modification through variation and natural selection
-based on observations from travel aboard the HMS Beagle (heavily influenced by pacific island flora and fauna) ADAPTIVE EVOLUTION
darwin’s evolution
evolution is the change in allele freq over time
dobzhansky’s evolution
-a heritable change in one or more characteristics of a pop or species from one generation to the next
brooker’s evolution
the diff btween brooker’s micro and macro evolution is ______ and _________ __ __________ _________
-brooker also hinges evo on _____________
time
degree of phenotypic change
speciation
group of individuals that potentially interbreed in nature
-problems (asexual organisms, ring species)
WHO??
biological species concept
Ernst Mayr
other problems with biological species definition
hybrids & introgression
chronospecies
secondary contract
each species is and independently evolving lineage ( a line of descent )
general lineage concept (deQuieroz)
habitat isolation temporal mating isolation sexual isolation mechanical mating isolation gametic isolation
prezygotic isolation mechanisms
hybrid inviability
hybrid sterility
hybrid breakdown
postzygotic isolation mech
biogerography + cladogenesis =
allopatric speciation
parapatric speciation
sympatric speciation
seq of events in evolutionary development
phylogeny
diagram depicting a phylogeny
phylogenetic tree
phylogenetic trees are based on _______
-having the same relation, common ancest.
homology
study of features that are (or are not) shared
cladistics (Willi Henig)
shared with distant ancestor
-arose longer ago
ancerstral characteristics
- not shared with distant ancestors
- arose more recent
derived character
molecular evolution 2 people?
DNA can be used to infer evolutionary relationships
Linus Pauling
Emile Zuckerkandl
evolutionary reconstructions
- typically based upon the analysis of DNA from extant species
- molecular clock( base upon ________ ____, ________ _____ calculated from fossils, which isn’t necessary)
phylogenetic tree
mutation rates
shared derived character
synapomorphy
a distantly related organism
outgroup
the monophyletic group in which we are interested
ingroup
the ________ polarizes the tree
out group
overall similarities/dissimilarities
phenetics
phenetic method of constructing phylogenetic tree
find most similar pair (humans and chimps 145bp)
calculate the avg number of nucleotide substitutions per species
( 145bp/2 = 72.5bp)
calculate the % nucleotide diffs
(72.5bp * 100)/ 10,000 bp = 0.725%
