Assessment 2 Flashcards
(45 cards)
What determines where an organism lives?
- Physiological traits and physical conditions (ex; salinity, temp, pH, sunlight, soil type, landforms, availability of oxygen)
- Interactions with other species: fundamental vs. realized niches
What time of organisms (sessile vs mobile) are tolerant of extreme conditions
Sessile, because they can’t move so they literally have to be
How do you measure organism performance?
photosynthetic rates, reproductive rates, size, athletic prowess
Energy Allocation
an organism can’t simultaneously maximize all of life’s functions. There must be a tradeoff between survival, growth, and reproduction.
Acclimation
physiological changes, not genetic changes/not evolutionary
Adaptation
cannot happen at the individual level
Poikilotherms
variegated (body temp varies with environment, “cold blooded”
Ectotherms
Use external heat sources, body temp varies
Endotherms
use metabolic heat sources
Homeotherms
use metabolic heat sources to maintain constant temp (this is us!!!) (also energy expensive)
Heterotherms
use both endo/ecto characteristics to maintain temp (bees bats and birds)
Tradeoffs for endotherms and ectotherms
ecto - have a lower resource demand (bc they don’t rely on metabolic) they can spend E on other things
endo - need to eat constantly to maintain metabolic rates
Biotic factors
interactions with other organisms (predation, competition, symbiotic relationships, etc)
Niche
role in an environment one species occupies, how it interacts with biotic/abiotic factors, deals with range of conditions species can tolerate and resources it can use.
Fundamental vs Realized Niche
fundamental = where a species can live (based on abiotic factors) realized = where a species does live (based on biotic factors)
Resource Partitioning
ex) birds sharing different parts of trees, or fish having different mouth parts that allow them to prosper on different parts of the coral.
Competition
(-/-) interaction
Population
same species in a specific area, that experience the same environmental factors, same resources, and can breed with each other.
Survivor Ship Curve Types
1: low death rates when young and middle aged, high when older
2: constant decrease, consistent risk of death
3: high death when young, “flat” risk when older
Life History
3 phases: life, reproduction, death.
This means age at first reproduction/death heavily influences populations!
R selection
high rates of reproduction
low survival
fast colonization after disturbances
exponential growth
K selected
outcompetes other species high investment in offspring low reproductive rates poor dispersal logistic growth
Basic model of population growth
take current year/year of interest and divide by past year
Exponential population
N1/N0 = lambda
