Unit 8 - Ecology Flashcards
Stimulus
external/internal signal/group of signals that cause a response (can be behavioral or physiological)
Behavior
response to a stimulus that can be due to genetic or environmental factors
- allows for survival and reproduction
Communication
animals exchanging information; used for dominance, find foot, establish territory, ensure reproductive success (find mates/care for young)
mechanisms:
- visual
- audible
- tactile (touch)
- electrical
- chemical
Aposematism
markings/behaviors that signal a WARNING
Pheromones
trigger a social response within the same species
Proximate Cause
{how} – what was the stimulus; how does “NURTUE” affect behavior
experiences during growth and development
Ultimate Cause
{why} – how does behavior help the animal survive/reproduce; how does “NATURE” affect behavior
evolutionary basis
Innate Behaviors
developmentally fixed; born with it
growth/development has NO EFFECT
Signal
stimulus generated, passed down from 1 animal to another
- pheromones
- stimulus response chain
- body movement (bee wiggle)
Fixed Action Pattern
sequence of unlearned acts directly linked to a stimulus
- unchangeable; carried out to completion
- triggered by external cue (sign stimulus)
fish seeing red and attacking even if it is harmless
Migration
innate behavior
Directed Movement
away/toward a stimulus
- kinesis: rate of movement
Types of Taxis
Photo: light
Chemo: chemical
Geotaxis: gravity
Learned Behaviors
depends on the environment; experience DOES EFFECT; high variability
Learning
based off experience (modification)
Imprinting
long-distance; happens during a sensitive period (early in life)
Spatial
memories based off spatial structure (cognitive map)
Associative
associate 1 environmental feature with another
Social
through observation and imitation of behaviors
Cooperative
team work
Altruism
decreases an individuals fitness but increases the populations fitness
Phototropism
directional growth toward light
Photoperiodism
development in response to day length, time of year
Endotherm
use thermal metabolism to maintain body temperature (heart rate, fat storage, etc.)
Ectotherm
uses external source to regulate body temperature (sun/shade)
Metabolic rate
O2 consumed, CO2 produced
- smaller organisms = higher metabolic rate
- larger organisms = lower metabolic rate
(SA:V ratio!!)
R-Selected
lots of offspring - ‘R’ats
- less energy efficient
- common in UNSTABLE environment with LESS resources
K-Selected
few offspring - ‘K’angaroos
- more energy efficient
- common in STABLE ecological environments
Auto vs Hetero - troph
Autotroph: makes its own food (plants)
Heterotroph: uses others as food (animals)
Primary Production
amount of light energy concerted into chemical energy
GPP = total, NPP = GPP - energy used
Water Cycle
essential for all life, influences rate of ecosystem processes
Carbon Cycle
essential for all life, required for organic compounds
Nitrogen Cycle
making amino acids, proteins, nucleic acids
Phosphorus cycle
makes amino acids, proteins, nucleic acids, ATP!
Factors that affect Population Growth
- when reproduction begins
- how often reproduction occurs
- # of offspring per episode
- survivorship till reproductive maturity
more food = more reproduction = more offspring survival = more population
Exponential
J-shape curve
ideal conditions (usually never happens)
Logistical
S-shape curve
limited resources, carrying capacity
Population Density
more resources = more reproduction = less space = more density
Density Dependent
competition, predation, territoriality, disease, reproduction rate
Density Independent
weather, climate, natural disaster
Survivorship Curve
I: low death rate early/middle, high death rate late
II: constant death rate
III: high death rate early, low death rate for those who survive early life
Ecological Niche
role/position a species has in its environment
Fundamental Niche
niche potentially occupied by the species if there were no limiting factors (predators, competition)
Realized Niche
portion of the fundamental niche the species actually occupies after taking in account of limiting factors
Species Composition
identify all species in a community
Species Diversity
variety of species and # of individuals in each species in a community
Richness
of DIFFERENT species
Relative Abundance
PROPORTION each species represents of all individuals of a community
Simpsons Diversity Index
higher index = higher biodiveristy
Interspecific Interaction
one species interacting with another
Competition
-/-
Predation
+/-
Cryptic Coloration: camouflage
Batesian Mimicry: harmless mimics harmful
Mulierian Mimicry: 2 or more bad-tasting individuals look similar
Herbivor
+/-
Symbiosis
Paratism: +/-
Mutualism: +/+
Comensalism: +/0
Trophic Cascade
removal or decrease of key stone species impacts species on a different trophic level
Niche Partitioning
decreased competition over limited resources between 2 similar species since they use resource in different ways
Diversity
increased diversity = increased resistance to environmental changes
stabilizes long-term structure of the ecosystem
less vulnerable to drastic changes
more diverse in TROPICS than in the poles
Abiotic
weather, water/nutrient/light availability
Biotic
presence of producers (for food, habitat, reduce erosion), key preditors (keep populations under control; diverse diet = no pressure on prey)
Keystone Species
NOT ABUNDANT
other species rely on them
- maintain diversity of the ecosystem
- impact size of other population in the community
- prevent overpopulation (frees resources)
Disturbance
event that changes a community by removing organisms/altering resource availability
Primary Succession
starts with just bedrock/rock
colonize previous lifeless ground
Secondary Succession
clears existing community but the soil remains (fire)
HIPPCO
Habitat loss - erosion, extinction
Invasive species - outcompete native species
Population growth
Pollution ———— both reduce capacity
Climate change—- of Earth to sustain life
Overharvesting - harvest faster than rebound; extinction
Pathogens
Disease
mostly affect new habitats
