Exam 3 Flashcards
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
Define “Dominant competitor”
the most aggressive/successful competitor for a resource
Define “Foundation species”
species that act as producers or ecosystem builders for many other organisms
What are the four kinds of species interactions?
Competition (-,-)
Predation, Parasitism (+,-)
Mutualism (+,+)
Commensalism (+,0)
What are the three types of interspecific competition
exploitative (no fighting)
interference (physical prevention)
competitive (Fight!)
Define “Fundamental Niche”
The niche that a species could fill in the absence of competitors
Define “realized niche”
the niche a species is restricted to in the presence of competitors
Define “Competitive release”
expansion of a species ecological niche when a competitor is removed
How do similar species coexist when their niches overlap?
Resource partitioning: Species will specialize by either reducing niche breadth, or increasing distance between peaks
List three types of morphological defenses
physiological
crypsis
aposematism
Define “Ecological niche”
All the environmental factors that influence the growth, survival, and reproduction of a species
What are the two types of seeding done by plants?
Mast seeding: lots of seeds produced by many trees all at once
Choose dispersal: Seeds contain toxins or bad tastes for some, agents are chosen
Define “Ecosystem”
the organisms in a particular area and the physical environment with which they interact
Explain the energy flow through ecosystems
organisms capture and store energy, then transfer some (about 50%) of it to organisms that eat them
Define “Biomass”
what is available to be eaten by the next trophic level
Define “evapotransportation”
moisture lost via evaporation
Define “multiplicative loss of energy”
The rule that states that at least 90% of the available energy is lost moving from one trophic level to the next
Define “ecological efficiency”
the percentage of energy transferred from one trophic level to the next
What is consumption efficiency
The percentage of total productivity (biomass) at one trophic level that is consumed by the next highest
remainder= not eaten
What is assimilation efficiency
The percentage of ingested food energy that is assimilated (digested) and thus is potentially available for growth and reproduction
remainder=excreted
What is production efficiency
The percentage of assimilated energy that is incorporated into new biomass (growth, reproduction)
remainder=lost as heat
What makes a species vulnerable to extinction?
- Vulnerability to introduced exotics
- over-exploitation
- rarity
Define “endemic”
a species that is only found in one small geographic range
what are some of the problems due to habitat fragmentation?
Edge effects (edges more vulnerable)
Smaller area (fragments)
Isolation (smaller populations)
what is a potential solution to habitat fragmentation?
habitat (movement) corridors that connect these “islands” and allow movement between them
Define “Biodiversity Hot-Spot”
a relatively small ecosystem with a high concentration of species, many of which are endemic. usually close to equator and associated with high primary productivity
