Sparks-Exam 2 Flashcards
ecology
organisms that interact with each other/environment
ecological hierarchy
ecosystem-community interactions with abiotic factors
community-group of individuals of 2 or more species in one place and time
population-individuals of one species in one place and time
organismal-behavior and evolution
how can ecology drive evolution?
something changes in the environment to result in evolution
how can evolution drive ecology?
species processes can derive into the environment
Altruistic
sacrifice organisms to have gene survival
organismal level- behavior/diet preference
foraging behavior
- food obtaining behavior
- recognize, capture, handle, consume
organismal level- optimal feeding strategy
- compromise between the benefits of the feeding and the costs of obtaining the food
- the optimal strategy has the highest net payoff
organismal level- altruism
- behavior that reduces fitness of the individual but increases the fitness of others in the population
organismal level-two types of net benefit
kin selection: altruistic acts that benefit genetic relatives
- benefits gained through shared genes (fitness)
-eg parent offspring
-ex. alarm calls of ground squirrels; calls relatives, risk life to help them survive
reciprocal altruism: altruistic acts that are provided to non relatives
- benefits occur when act is reciprocated
- in humans its friendships
- conditions that favor reciprocal altruism such as social groups, longterm association, memory, individual recognition, punishment
organismal level-reproductive behavior
- mate choice (inter-sexual): females choose from variety if mates; vice verse; mostly females look for quality
- male/male competition (intra-sexual): males compete w/ each other for females
- female/female competition (intra-sexual): females compete w/ each other for males
Mate choice mechanisms
- Good genes: payoff to the females through increased genetic quality of offspring
- females find good genes in males to produce
offspring with better survival genes - Direct (material) benefits: payoff to females through access to resources
- females are protected by males to find
resources from other territories
- eg food on male territory
Mating systems
- local ecology
- past evolution (selection pressures/phylogenetic relationships)
- ability to reproduce
1. Monogamy (1 female: 1 male)
2. Polygyny (1 male: multiple females)
3. Polyandry (1 female: multiple males)
4. Polygynandry (multiple males: multiple females)
Monogamy
- western gulls; males/females share parental behavior
- offspring won’t survive w/o both parents
- not many monogamists bc of extra pair populations which was revealed through genetic data analysis w/o observes knowledge
polygyny
- elk; females group together to fight predators white males fight to be female groups
polyandry
- red necked phalarope; females larger than males
- nest failure is common, don’t need both parents
- males care for eggs
polygynandry
- amphipods
- males: more matings
- females: more genetic diversity in offspring
- no co-raising offspring
- beneficial when conditions are very variable; different combinations of of genotypes with different males and females raise different variants of offspring
lots of variation in diverse environments
Communication
transfer of information from a signaler (sender) to a receiver
- signals: acoustic, vibrational, chemical, visual
Signals
- Honest Signal: costly produce, can’t be bluffed, reliable indicator of quality
- Dishonest Signal: signal used to manipulate receiver, distraction display
ex. “broken” wing bird leads prey away from nest
Receivers
- Legitimate receiver (intended receiver): potential mate, opponent, predator
- illegitimate receiver (unintended receiver): interceptor, predator
Alarm signal- evolution
- used to warn others
- in some cases intentional
- sometimes unintentional; by products of attacks
- aquatic systems: alarm cues, minnows, chemicals in skin predator attack warns others, chemical would be commonly present in skin
population ecology
study of populations in relation to the environment
population dispersion
- clumped: patchy distribution of resources (eg food), se stars
- uniform: equally spaced, direct interactions, territory protection, gulls
- random: unpredictable spacing, abiotic dispersal, wind dispersal of seeds
life history traits
- age at maturity
- size at maturity
- offspring number
- offspring size
- lifespan
Pattern allocation
- energy tradeoffs: how much energy is given to each trait; follows trait w/ more energy
- life history tradeoffs:
- more eggs; smaller
- less eggs; bigger size
life history evolution
number of reproductive events
- iteroparity: multiple reproductive events
(eg amphipods; fuck whoever; whenever)
- semelparity: one reproductive event
(eg salmon; die after giving birth once)
population demography
- pattern of mortality & survival
- age related
- survivorship curves
survivorship curves
plot of proportion of original cohort alive at each age
- type I: mammals, humans
- type II: ground squirrels, lizards, birds
- type III: oysters, barnacles, plants, fungi
type I
high survival early, drop steeply at old age
- large investment in each offspring
- high level of parental
type II
constant pattern of survival/mortality throughout life
- intermediate investment in each offspring
- intermediate levels of parental care
type III
low survival early, few survivors live a long time
- small investment in each offspring
- low level of parental care
population growth
change in population size over time
- exponential growth: no limits
- logistic growth: limits set by k
- k = carrying capacity: # of individuals of a species that can be supported in an area
- N vs time
exponential growth
- no limits
- unlimited resources
- no competition
- some organisms in specific solutions
Logistic growth
- limits
- resources limited
- competition (infraspecific-within species)
- most organisms
exponential growth
b > d –> r more than 0 ; population increases
b < d –> r less than 0 ; population decreases
b = d –> r = 0 ; no change in population change
equation= rN
logistic growth
- exponential growth initially
- limits occur larger at N
- limits set by k
equation = rN[k-N/k]
population regulation
Density Dependent Regulation: population growth regulated by density related factors that decrease growth
- increased d at high N
- decreased b at high N
- increased d and decreased b at high N
Density Independent Regulation: population growth can be regulated by factors that are unrelated to population size (fire, flood, etc)
