biological stuff Flashcards
dispersal ecology
study of movement for breeding/growing
dispersal ecology types
-seed
-animal
dispersal ecology causes
natal
evolutionary forces
3 stage movement of dispersal
- emigration or departure
- transfer, transience, vagrant
- immigration or settlement
dispersal vs. migration
dispersal establishes new colony in new area
migration travels and returns
evolutionary forces in dispersal
- gene flow
- avoids competition and interbreeding
- increases variance in expected fitness
- allows escape from unfavorable conditions
- may be costly…
seed dispersal
- water
- wind
- animals
- bursting
animal dispersal
natal
leaving nest prior to first reproduction
animal dispersal
breeding
movement between breeding episodes
animal dispersal in male mammals
-move away from nest (sex-biased dispersal)
-dispersers
animal dispersers in female mammals
- remain near home
- philopatric
dispersal internal state (phenotype)
- physiology
- behavior
- morphology
- life-history traits
dispersal external factors (condition)
- inbreeding risk
- kin competition
- intraspecific (species) competition
- habitat quality
- outbreeding risk
dispersal transfer of information
- departure
- transience (YOLO)
- settlement
genetic diversity
the total genetic information contained in all individuals in a population, group, species, or group of species
source of genetic diversity and variance?
mutations (new alleles)
recombination (new combinations)
genetic diversity determines
adaptive capacity of population or group
how species diversity is measured
- species richness
- species diversity
richness
count of how many species are in one area
species diversity:
measure that incorporates both richness and evenness
what changes species diversity?
- speciation
- extinction
- changes in climate
ecosystem diversity
variety of biotic components in a region along with abiotic
ecosystem function
sum of biological and chemical processes that are important in an ecosystem
top 5 threats to biodiversity
- habitat destruction
- overexploitation
- invasive species
- pollution and disease
- climate change
habitat destruction
complete removal or destruction of a habitat
habitat degradation
change (reduction) in the quality of a habitat
habitat fragmentation
process by which a large expanse of habitat is transformed into a smaller number of isolated areas
habitat fragmentation effects
interior habitat species decrease
exterior habitat species increase
how are habitat fragmentations different than original
- smaller area
- less interior habitat (think radius)
- more “edge” (think perimeter)
- isolated
implications for bio communities
-change in species richness
- changes in habitat type mean changes in species composition
overexploitation
overharvesting
overhunting
overfishing
effects of overexploitation
- decreased population size
- decrease in average size of individual
- potential for extinction
what makes invasive species successful
- rapid growth
- wide range in diet
- good at dispersing
why do invasive species thrive
- few natural predators
- good competitors for food
- low susceptibility for native disease
what areas are most likely to be invaded by invasive species
-edge habitats
- early successional areas
- remote islands with low diversity
- remote islands with no predators
