Download Ecology Exam 2 | BIOL 210 - Intro to Ecology and Evolution and more Quizzes Ecology and Environment in PDF only on Docsity!
define population
group of individuals of the same species occupying the same area TERM 2
demography (2 ex)
DEFINITION 2 study of population dynamics for example: -patterns of growth -age & sex composition TERM 3
Geographic range & factors affecting it (3)
DEFINITION 3 def: overall distribution of population factors: -tolerance limits by species -barriers to dispersal (bodies of water, mtn ranges) -individuals restricted to suitable habitat within overall range includes where population exists at all stages in life cycle TERM 4
Clumped dispersion pattern (3)
DEFINITION 4 caused by: -clumped resources -advantages in group living (defense/ increased foraging success) -tendency of offspring to stay close to their parents TERM 5
uniform/spaced dispersion pattern (2)
DEFINITION 5 caused by: -competition for resources -needing more space to grow
Random Dispersion Pattern (2)
uniform environment no interaction with other species TERM 7
Why are dispersion patterns formed?
DEFINITION 7 unconformities in the habitat TERM 8
factors affecting the ability to disperse
between subpopulations (3)
DEFINITION 8 -degree of unsuitability of intervening habitat -distance between subpopulations -mobility of species TERM 9
3 models of subpopulations
DEFINITION 9 metapopulation source sink model landscape model TERM 10
metapopulation
DEFINITION 10 sub populations occupy patches of a particular habitat type between which individuals move occasionally
red queen hypothesis
evolutionary hypothesis explaining why most organisms reproduce sexually because organisms are constantly attacked by parasites and disease... there is pressure to create genetically variable offspring so that some of them have a chance of beating the disease of parasite. essentially, keep running to stay in the same place... stay one step ahead to stay alive TERM 17
ecological factors that determine dispersion
of individuals (2)
DEFINITION 17 resource distribution, predation risk TERM 18
dominance heirarchy
DEFINITION 18 individuals coexist, but do not share resources equitably TERM 19
territoriality
DEFINITION 19 individuals defend exclusive access to the resource TERM 20
3 types of territories
DEFINITION 20 all purpose, feeding, mating
economic defensibility
benefits of territory ownership outweigh costs TERM 22
benefits (2) & costs (3) of defending a
territory
DEFINITION 22 benefits: exclusive access to resources and mates, more efficient use of time costs: time and energy spent on territorial defense, increased exposure during defense, risk of injury TERM 23
benefits (3) & costs (3) of living in
groups
DEFINITION 23 B: reduced predation risk, increased foraging success, more parental care C: competition, disease, risk of exploitation TERM 24
protective benefits of group living (4)
DEFINITION 24 dilution effect: central individuals also shielded by peripheral individuals (selfish herd), confusion effect, early warning of predators, cooperative defense TERM 25
foraging benefits of group living (3)
DEFINITION 25 copying, reduced viligance per individual; more time available for foraging, cooperative prey capture
inclusive fitness
direct + indirect fitness TERM 32
when is altruism favored?
DEFINITION 32 when Br > C B = fitness benefit to recipient r = coefficient of relatedness C = fitness cost to donor TERM 33
Eusocial insects
DEFINITION 33 most altruistic sterile females develop from fetilized eggs (diploid) males develop from unfertilized eggs (haploid) Queens share 50% of genes w/ offspring Workers share 75% of genes with offspring workers are more closely related to others than to owm potential offspring TERM 34
types of asexual reproduction (3)
DEFINITION 34 budding, parthenogenesis, propagules TERM 35
implications of asexual reproduction
DEFINITION 35 offspring are genetically identical to parents and each other... clones
costs of sex 3
time and energy costs: male aquisition, attraction of pollinators cost of meiosis: each parent passes on half as much DNA (female cost is reduced if males contribute lots of parental care) TERM 37
why sexual reproduction?
DEFINITION 37 meiosis produces new genetic combinations, increasing parents reproductive success if offspring differ genetically, it is likely that more offspring will survive environmental change. TERM 38
dioecious
DEFINITION 38 individuals of separate sexes TERM 39
monoecious:
DEFINITION 39 both male & female organs (hermaphroditic) TERM 40
simultaneous hermaphrodites
DEFINITION 40 possess both sex organs at the same time: snails, flatworms, earthworms
