Ecology Flashcards
The kārearea breeds only in Aotearoa, it is therefore considered to Aotearoa…. Endemic?Introduced?Native?
Native
Island endemism can
lead to…
Giants, dwarfism, k-selected unique behavioral traits
unusal feature of nz birds??
Flightless, lack of fear, smelly, competitiveness, convergent evolution
convergent evolution is…
similar characters evolve independently in two species in
response to similar selective pressures (same “niche”)
similarity in niches leads to similarity in morphology and
behaviour even if not closely related phylogenetically
New Zealand is the _____ what capital of the world
sea bird
NZ features…
Bird features
Bird dominance
Many taxa missing Depauperate (missing many groups) but rich (wide speciation in some groups which are here)
Behaviour
is the way an organism acts in a particular situation
What affects species distribution
Abiotic factors, Biogeography, Biotic interactions, Behaviour, Dispersal
Animal behaviour //learning
How do animals learn?
What do they learn?
Animal behaviour //Cognition
How ‘smart’ are animals?
Neurobiology
What is the neural platform of behaviour, and does
experience change it?
How can behaviour be flexible?
Physiology
What is the physiological platform of behaviour?
How do hormones affect behaviour and vice versa?
Ecology
How is behaviour affected by habitat, trophic level, and
competition?
How does the behaviour of one species affect others?
Genetics
What is the genetic basis of behaviour?
Can behaviour drive selection of certain genotypes?
Ethology:
the study of behaviour
Behavioural
ecology:
how behaviour is controlled and how it develops, evolves, and contributes to survival and reproductive success.
Tinbergen’s “four
questions”about animal
behaviour
Mechanism, Development, Function, Evolution
Which of Tinbergen’s questions are proximate
Mechanism, Development,
Which of Tinbergen’s questions are Ultimate explanations
Function and evolution
What is a proximate cause
causation within individual
HOW a behaviour works
Development, physiology
Ultimate causation
Causation within populations
WHY a behaviour evolved
Function, evolution
Natural selection
In individuals
Individuals are selected for or against, which in turn causes evolution within a population.
Natural selection favours behaviour that increase the inclusive fitness of individuals.
Stimuli
Examples of a stimuli
Light: black & white vs colour, range of
colours detected, low
-light sensitivity,
polarization
Sound: frequency range, sensitivity
Scent (and its water equivalent)
Tactile (vibrations) Electric fields Magnetic fields
Stimuli can be..
Stimuli can be abiotic, inter
-specific, or intra
- specific
Signal
A stimulus from one animal that causes a change in another animal’s behaviour.
Communication
is the reception of and
response to signals.
Learning
The modification of behaviour based on specific
experiences- ranges from very simple to very complex.
“ Learning is an enduring change in the mechanisms
of behaviour that results from experience with
environmental events”
Innate behaviours
Have a strong genetic component and are largely
independent of environmental influences
Developmentally ‘fixed’ (not learned) Does not need to be practiced, but can improve with experience
Kinesis
or the undirected movement in response to a stimulus.
Taxis
the directed movement towards or away from a stimulus.
Migration ( and is it innate or not)
is the long-range seasonal movement of
animals. It is an evolved, adapted response to variation in resource availability, and it is a common phenomenon
found in all major groups of animals.
Fixed Action Patterns (FAP):
A sequence of
unlearned, innate behaviours that is
relatively unchangeable triggered by a sign stimulas
Greylag goose
egg-retrieval
response
Innate behaviour, once started the behaviour must be completed
Stimulus
Sign stimulus or Releasers
Recognition
Innate releasing mechanism
A structured Behavioural response
Fixed action pattern
Supernormal stimuli
A fixed or flexible behaviour can be triggered
by certain innate stimuli
Sometimes an exaggerated, unrealistic version
(supernormal stimulus) is even more attractive
than the real thing
Imprinting
is a type of
behaviour that includes both
learning and innate
components- generally
irreversible
Spatial learning
learning their enviroment.
Enviroments are patchy, An animal’s fitness may be enhanced by a capacity for spatial learning e.g. location of home, nest sites, food sources, danger
Associative learning
when the animal learns
to associate one stimulus with another
Social learning is…
Cultural transmission
Cognition
is the ability of an animal’s nervous system
to perceive, store, process, and use information
gathered by sensory receptors
complex learning includes cognition
Foraging
recognising, searching for, capturing,
handling, and eating food items
Optimal foraging
Views foraging
behaviour as a compromise between benefits of nutrition and costs of obtaining food (e.g., predation risk and energy
expenditure). choose profitable pray
Altruism:
an act that benefits the recipient but harms
the donor.
Kin selection
selection in which individuals increase their inclusive fitness by helping increase the survival and reproduction of relatives (kin) that are not offspring
Attributes of cooperative breeders
- Live in groups
- Several adults
help with offspring
– Defense
– Prepare/maintain
living area
– Feed young
Life history
Characteristics of species which impact the
timing and form of major “life events”, including:
* Body size
* Survival
* Age at reproductive maturity
* Number of offspring it produces
Success
surviving offspring.
Principle of allocation
There is limited energy,When energy is allocated to one
function, it reduces the energy available
for other functions
Time energy budget
Tradeoff occur due to the budget
What are the 3 main tradeoffs
reproduction vs growth
reproduction vs survival
Size vs number of offspring
Fecundity
is the potential reproductive capacity of an individual within a population.
r-selected trait life history traits
size: small
pop growth rate: fast
lifespan:short
Number of seeds :high
seed dispersal
Which traits to species optimise
Species optimise traits which leads to a few
successful strategies (set of related traits)
Population
Individuals of the same
species that co-occur in space and time
Population size in the future = Population size now +/‐ what?
Nt+1 = Nt + B + I – D – E
Within population equations what does BIDE stand for… which are the only factors and which a pop can change
B= births
I= Immigration
D= Death
E= Emigration
Demography
is the study of factors affecting a population (especially its numbers)
Pop size=
= total number of
individuals.
Expressed as a count (whole number)
Pop density=
the number of individuals within a specific area or volume.
Type of survivorship curves
Type I
low death rates during early and middle life
Type of survivorship curves
Type II
the death rate is constant over the life span
Type of survivorship curves
Type III
high death rates for the young, then a slower death rate for survivors
Why doesn’t exponential growth continue indefinitely?
Because resources aren’t unlimited!
Carrying capacity
The population size at which POPULATION growth
stops is called the carrying capacity, or K.
Genrally number of individuals of a particularspecies that the local environment can support.
K is reached when
caring capacity
K is reached when:
#birth + #immigration = #death + #emigration
R- selection
favors life history traits
Favours life history traits that are good in
exponential growth phase
(e.g. after disturbance)
live fast, die young, many small offspring
K-selection
favours life
history traits that are
good in crowded phase
(e.g. stable habitats)
Slow and steady, few large offsprings
Key points of pop growth
All populations can show exponential growth, but usually not for long
Limiting resources create logistic growth
Since population growth is logistic, why are population sizes not always stable?
3 classifications of species interactions
Taxonomic (species involved)
Function (what is being done)
Outcomes (impacts on fitness)
Taxnomic //interspecific
Among individuals of a different species
Taxnomic //intraspecific
Among individuals of the same species
Types Function:
Trophic (feeding) interactions
Reproductive interactions
Habitat related interactions
Mutalism
++
Commensalism
0+
Neutralism
00
Exploitation
-+
Amensalism
-0
Competition
–
Parasitoids:
An adult lays eggs in/on prey, and its offspring kill
the prey, but not immediately. Oh, there are also hyper‐
parasitoids.
Endo vs Exo parasites
Endo live within
Community
is a set of potentially interacting populations of different species
Pops are limited by…
Inherent life-history
Abiotic factors
Species (biotic) interactions
Population Limiting dependant factors// Density driven
Territoriality, Disease / parasites
Population Limiting independant factors// Density driven
Abotic, temp, rainfall, pollutants
How do individuals respond to density driven limiting?
dispersal, dormancy
interference competition
direct aggressive interaction
between individuals.
Exploitative competition:
competition to secure
resources first.
Competition
where individuals have a shared need for a
limited resource
Leads to lower growth or survival of (some of) the competing individuals
Niche
The set of environmental conditions
(abiotic and biotic) in which an organism
can survive and reproduce.
Fundamental niche
Physical conditions under which a species might
live in the absence of interactions with other
species
Realised niche
Physical conditions under which a species might
live when restricted by interactions with other
species
Competitive exclusion principle
No two species can occupy the same realized niche;
eventually one will out-compete the other or // Or they will have niche partitioning or resource
partitioning or some other coexistence mechanisms
Geographical range
And what dictates it?
Spatial area where a species is found.
The variety of optimal conditions for a species dictate it’s geographic range
Keystone species
play a crucial role in maintaining ecosystem structure
prevent other species from taking over an area
allow other, less-competitive species to flourish
Disturbance
an event that damages andremoves biomass
eg: windstorms, fire, snowbreak, landslide,
drought, floods
Ecological succession +
Primary vs secondly
After distrubance
is the sequence of community and ecosystem changes after a disturbance
Primary = no soil
Secondary+ soil remains after disturbance
Intermediate disturbance hypothesis
(IDH)
moderate levels of disturbance allow greater diversity than either high or low levels of disturbance
Ecology=
Scientific study of the relationship between organisms and their enviroment
*Physical
*Chemical
*Biological
Abiotic
non-living
Biogeography
study of the geographic distribution of living things and the abiotic factors that affect their distribution
Factors delineate: aquatic Biomass
Salinity
Water movement
Light
Temp
Oxygen
PH
Species and their environmental limits
Range of tolerance
Limits of tolerance
Zones of stress
Optimum range of tolerance
Every species has an optimum range, zones of
stress, and limits of tolerance for every abiotic
factor
Major abiotic factors
Temp
light
water
soil
salnity
Biome
Way of categorizing ecosystems. Often distinguished by their dominant plants and climates (terrestrial),
or the movement and physical properties of water (aquatic).
Latitudinal gradients and species richness
Species richness generally increases from middle and high latitudes to the equator.
Species richness
a count of the number of species in a given area
Ecology studies
Distribution and abundance of organisms
A major role in species distribution
Abiotic factors
Nz is unique due to…
very isolated
temperate, very oceanic climate
mountainous
history of major disturbances (tectonic,
glacial, human)
K species life history traits
Produce few, largeroffspring
Larger body size
Reproduce later in life
Slow development
High competitive ability
Species life History
Series of events over its lifetime, such as how resources are allocated for growth, maintenance, and
reproduction.
Life history// adaptation of organisms that influence biology
- Body size
- Survival
- Age at reproductive maturity
- Number of offspring it produces
Animal communication……
Animals communicate to their own species and to others
This can be cooperative or (often) selfish
It can be honest or dishonest (truthful or lying)
Factors limiting pop size
Pop denisty
Density-dependant factors
Density-independant factors
Foraging
recognising, searching for,capturing, handling, and
eating food items
Optimal foraging
Views foraging behaviour as a compromise between
benefits of nutrition and costs of obtaining food (e.g., predation risk and energy
expenditure). Predators choose profitable prey
Evolutionary response:
character displacement
Traits for two species are more divergent when the species occur together (sympatric) than when they occur apart (allopatric)
An evolutionary change that occurs when two similar species inhabit the same environment. To try minimise niche overlap
Example of social behaviour
Mutal grooming
protection of young
Highly complex societies
Species living within enviroment limits
*optimum range
*range of tolerance
*Zones of stress
A certain level where organisms grow, survive, or
PERFORM the best
Range of tolerance: the entire range allowing any
growth
Limits of tolerance: the high and low ends of the
range of tolerance
Zones of stress: between the optimal range and
high or low limit of tolerance
Multiple scales of relationships
Individual>Popualtion> community > ecosystem > biome > biosphere
What effects species distribtions
Abiotic
Biogeography
Dispersal & demography
Behavior
Biotic interactions
wowowo\
fjfj
