evolution in real time and conservation Flashcards
what is evolution in real time?
evolution in action and on time scales we can choose
macro-evolution is…
patterns of evol change above a species level
slow and gradual
e.g. evolution of new phyla
micro evolution is…
changes within a species
very small changes that can happen very rapidly
e.g. peppered moth
rapid evolutionary change is driven by…
competition
exploitation
climate change
parasites
competition drives… by….
natural selection within and between species (enhancement of characteristics e.g. bill/small beak size) by intra (within) and inter (between) specific competitions
evolution is…. likely to occur than extinction because….
less likely because extinction is faster
Darwin’s finches
inter species competition forced them to inhabit different niches
hybridization
when two genomes combine and offspring is not viable to reproduce with either parents’ genomes
v fast speciation
Grant and Grant studied…
changes in bill size in response to competition between G.Fortis and G.Magnirostris
rates of change were v close to predicted from heritability of the trait
Exploitation is….
Artificial selection
works in the same way at nat. sel.
v fast evolutionary response
describe and explain the point on the g. fortis beak size/ year graph for
a) drought
b) competitor established
c) competition increase
a) sharp declines in beak size - smaller seeds are more available
b) gradual decline - competitor has advantage
c) rise of competitor and drought combined
selective hunting 2 examples and effects
big horned sheep - largest animals selected and shot, removes genes from gene pool
leads to reduction in animal size and horn length, fluctuations in population size
larger cod fished for - smaller fish/ growth rate ang younger sexual maturity selected for
Climate change effect on animals
organisms evolve to one set of conditions but they are changing v quickly and cant evolve fast enough so going locally extinct ;((
causing change of distribution e.g. birds in uk
phenology define, effect and example
timing of life history events during the course of a year
is being disrupted due to climate change
ensures survival and reproduction
british flowers are flowering earlier and earlier as is better to flower early in poor env.
co-evolution with parasites is… , example
fast
rabbits(pest) and myxoma virus (introduced to control)
effectiveness decreased the more times virus was introduced 99-90-40/60
virulence stabilized at a lower level
selection pressures host and parasite
parasite pressure to be less deadly so can spread more
rabbit pressure to have higher resistance
measles vs flu
measles- no selection, random spreading
flu- reflects nat. sel. (undergoes selection and mutation)
consequences of change
reduce population size
extinction of population and species
loss of ecosystems
PNC
phylogenetic niche conservation
conservatism results form…
low rates of adaptability and evolution in phylogenetically similar groups (important in PNC)
IUCN threat
measure of how likely populations are to become extinct in coming years
purvis et al 2006
Uses statistical analysis to compare threats and Life history & ecological variables
correlations with extinction threat - carnivores
Geographic range
Gestation time
Trophic level
Human footprint
correlation with extinction threat - primates
Geographic range size
Body Size
Population density
Human density
is phylogeny a good indicator of extinction threat? explain
YES Geographic range size - no Body Size - yes Gestation time - yes Trophic level - yes IUCN threat - yes
