Exam 3 Flashcards
(49 cards)
What are the four derived traits of Chordates
- Notochord
-Dorsal, Hollow nerve cord - Pharyngeal slits
- Postnatal tail
Define “vertebrate”
A class or organism with a “head” and vertebrae
What are the advantages of Jaws?
breathing and catching food
Define “ecology”
Scientific study of the interactions of organisms with their abiotic and biotic environments
Define “Biotic”
Living organisms (predators, prey, symbiosis, pollination)
Define “Abiotic”
Non-living organisms (temperature, precipitation, weather)
Define “Population”
A group of individuals of the same species that live in a particular area and can interbreed
What are Life History Characteristics?
a link between individuals and populations. Examples include growth, change of form, dispersal, and timing of reproduction
List the three main life history strategies
1) Survivorship (lifespan)
2) Maturity (age at first reproduction)
3) Reproductive output
list the two types of reproductive output
Parity- reproduce once
Iteroparity- repeated reproduction
Define “fecundity”
the number of offspring per reproductive episode (more offspring linked to low survival rate)
Define “parental investment”
energetic effort put into offspring, more effort = less offspring with higher survival rate
What is the rule that governs Life history strategies?
Energetic tradeoff, compromises in the allocation of energy
Define “Philopatric”
returning to breeding site year after year
What types of diversity factor into biodiversity
Genetic diversity, species diversity, and ecosystem diversity
what are the assumptions made with the mark/recapture technique
closed population (no immigration/emigration)
no births/deaths within sampling period
marked/unmarked are equally likely to be caught in 2nd sampling
Define “Community”
Any assemblage of populations of plants and animals in a given area or habitat
Why is high community biodiversity important?
These communities are more productive, stable/able to withstand and recover from environmental strass, and more resistant to invasive species
what is the biophilia hypothesis
Humans possess an innate tendency to seek connection with nature and other forms of life
How do you quantify biodiversity?
through species richness, evenness, and diversity
Explain bottom up control (food chains)
Bottom up: In an ecosystem/food chain each level regulated by the level below
Explain the green world theory (trophic cascade)
Top Down control, in an ecosystem/food chain, each level is regulated by the level above
What are the patterns of trophic cascades?
if there are an off number of trophic levels, vegetation increases. with an even number, vegetation decreases
Define “Keystone species”
A species that maintains the biodiversity of a community or a species with a small population that has a disproportionately large impact on the other species in the community
