Ecology and Behaviour Flashcards
the changes in allele frequency that occur over time within a population due to mutation, selection, gene flow, gene drift, and nonrandom mating
microevolution
the patterns of changes in groups of related species over broad periods of geologic time; patterns determine phylogeny
macroevolution
What was Lamarck’s theory?
Use and Disuse
-body parts can develop with increased usage and unused parts are weakened
-inheritance of acquired characteristics: body features acquired during lifetime can be passed to offspring
-natural transformation of species: organisms produce offspring with changes, transforming each later generation to be slightly more complex
What is Darwin’s theory?
Natural selection
- survival of the fittest, allele frequencies increase or decrease in order to adapt to the environment
- descent with modification: over time, traits with reproductive advantage will become more common
the development of an organism
ontogeny
the evolutionary development and diversification of a species
phylogeny
What is the evidence for evolution?
- Fossils
- Biogeography
- Embryology
body parts that resemble one another between different species that descended from a common ancestor (bat wings vs. bird wings)
homologous structures
body parts that resemble one another between different species that evolved independently (bat/bird wings vs. bee wings)
analogous structures
ability to survive and produce fertile offspring
fitness
What is stabilizing selection?
bell curve favours an intermediate, like how the average height in humans is in the middle
a group of individuals capable of interbreeding
species
What is industrial selection?
the selection of dark coloured, melanic, varieties in various species of moths as a result of industrial pollution (type of directional selection)
What is disruptive selection?
when the environment favours extreme or unusual traits while selecting against common traits
differential mating of males or females in a population
sexual selection
females choose superior males, which increases fitness of the offspring
INTERsexual selection
males compete and fight with other males for better mating opportunities
INTRAsexual selection
the differences in appearance of males and females
sexual dimorphism
this is a form of directional selection carried out by humans when they breed favourable traits, and is not natural selection
artificial selection
mating with unrelated partners resulting in mixing of different alleles and creating new allele combinations
outbreeding
the coexistence of two or more phenotypes
polymorphism
What is heterozygote advantage?
heterozygote condition has greater advantage than either homozygous conditions
Ex. sickle cell anemia is recessive, heterozygous trait is resistant against malaria
What is punctuated equilibrium?
the hypothesis that evolutionary development is marked by isolated episodes of rapid speciation between long periods of little or no change.
What is frequency-dependent selection (minority advantage)?
occurs when least common phenotype has selective advantage
Ex. predators use search images of common phenotypes to find prey, allowing prey with rare phenotypes to escape. The rare prey phenotype eventually becomes common and cycle repeats
variations that are passed down without any selective value, such as fingerprints in humans
neutral variation
variation of a species dependent on climate or geographic conditions
geographic variation
the increase and decrease of allele frequencies due to adaptations to the environment
natural selection
the introduction and removal of alleles from the population when individuals leave (emigration) or enter (immigration) the population
gene flow
the random increase and decrease of an allele by change, has a larger effect on small populations
genetic drift
What is the composition of the modern atmosphere?
occurs when the population undergoes a dramatic decrease in size due to natural catastrophes or events, gene pool is much smaller and population vulnerable to genetic drift
bottleneck effect
What are the two types of nonrandom mating?
1) inbreeding - individuals mate with relatives, changes genotype but not allele frequency
- sexual selection - females choose males based on superior traits
a small population of the same species that regularly interbreed; beavers along a river
deme
What are the equations for hardy weinberg?
Example of a Hardy-Weinberg problem:
A plant population has 84% red flowers and
16% white flowers. The red allele (R) is
dominant and the white allele (r) is recessive. Write out the % of dominant and recessive alleles and the frequency of homozygous dominant, heterozygous and homozygous recessive.
- 16% white flowers can be written as: q2
= 0.16. Taking the square root to find q
will equal 0.4 - 0.4 can then be plugged into “p + q =
1” to get “p + 0.4 = 1.” Solving for p
equals 0.6 - Plugging 0.6 into p2 results in 0.36
- Plugging 0.6 into 2pq results in 0.48
p = 0.6 (60% of the alleles are R)
*See picture for rest
a relationship between two species
symbiosis
when the population is divided by a geographic barrier
allopatric speciation
the formation of a new species without the presence of geographic barriers
sympatric speciation
possessing more than two sets of chromosomes
polyploidy
possessing more than two sets of chromosomes, both of which are from the same parental species
autopolyploidy
possessing more than two sets of chromosomes, but they come from different species
allopolyploidy
two different closely related species mate and produce a hybrid along a geographic boundary called a hybrid zone
hybridization
the rapid evolution of many species from a single ancestor
adaptive radiation
What is prezygotic isolation?
prevents fertilization before mating is attempted, zygote not formed
- Habitat isolation - species do not encounter eachother because they live in different habitats, even if they are in the same geographical area
- Temporal isolation - species reproduce at different seasons/times
- Behavioural isolation - some species will not reproduce with eachother if they do not perform the correct courtship rituals
- Mechanical isolation - occurs when male and female genetalia are not compatible
- Gametic isolation - male and female gametes do not recognize eachother
What is postzygotic isolation?
if a zygote dose form, there are methods to maintain isolation
- hybrid inviability - zygote fails to develop properly and dies before reaching reproductive maturity
- hybrid sterility - hybrids become functional adults but cannot reproduce
- hybrid breakdown - hybrids produce offspring that have reduced viability/fertility, hybrid’s children cannot reproduce
this type of evolution occurs when two or more species that originated from a common ancestor become increasingly different over time as a result of speciation
divergent evolution
this type of evolution occurs when two unrelated species evolve to share more similar traits due to adapting to a similar environment (analogous traits)
convergent evolution
this type of evolution occurs when two related species make similar evolutionary changes after their divergence from a common ancestor
parallel evolution
this type of evolution occurs when two related species make similar evolutionary changes after their divergence from a common ancestor
parallel evolution
this evolution occurs when two species each causes the other one to evolve, which results in the evolution of both species
coevolution
evolution occurs by gradual accumulation of small changes
phyletic gradualism
relationship is beneficial to both species
mutualistic
What was the atmosphere like in the early Earth?
CH4, NH3, CO, CO2, H2, N2, H2O, S, HCl, HCN
little to no oxygen
What did Oparin & Haldene do?
- proposed organic soup theory
- said if o2 was in primordial atmosphere, no organic molecules would form because oxygen is reactive
- environment must be reducing because if it was oxidizing then complex molecules would have broken apart
What did Oparin & Haldene do?
- proposed organic soup theory
- said if o2 was in primordial atmosphere, no organic molecules would form because oxygen is reactive
- environment must be reducing because if it was oxidizing then complex molecules would have broken apart
What did Stanley Miller do?
- tested Oparin’s theory and produced organic molecules
- sealed ammonia, methane, water, and hydrogen in a flask and simulated lightening
relationship is beneficial to one species and neutral to the other species
commensalism
structures that appear useless but had ancestral function; appendix is an example
vestigal structures
two or more harmful species that are not closely related but share one or more common predators, have come to mimic each other’s warning signals
Mullerian mimicry
harmless species has evolved to imitate the warning signals of a harmful species directed at a common predator
batesian mimicry
all the alleles for any given trait in the population
gene pool
speciation pattern in which populations speciate while in contact along a common border
Parapatric speciation
occurs when peripheral populations become geographically isolated from the main population and undergo genetic divergence and speciation
Peripatric speciation
the gradual evolution of a species without any branching, a straight path of evolution
anagenesis/ phyletic evolution
a group of species that includes a common ancestor and all of its descendants
a particular stage of an ecosystem
sere
an organic matter that leaves an impression in rocks or in inorganic matter
mold
a type of fossil formed when a mold is filled in
cast
relationship is beneficial to one species but detrimental to the other species
parasitism
Give examples of autotrophic anaerobes
chemosynthetic bacteria
Give examples of autotrophic aerobes
green plants and photoplankton
Give examples of heterotrophic anaerobes
yeast
Give examples of heterotrophic aerobes
amoebas, earthworms, humans
shared traits derived from an evolutionary ancestor common to all members of a group
synapomorphies
What is the law of parsimony?
Occam’s Razor
The fewest number of changes with respect to synapomorphies is likely the correct representation of reality
What is a simple reflex?
rapid, involuntary response to a stimulus
“knee jerk”
What are complex reflexes?
startle response
These behaviours are innate, or inherited. An example would be in mammals who care for their offspring by female parents
instinct
What is a fixed action pattern?
What are the three types of phyletic groups
What is imprinting?
the process by which certain animals form attachments during a critical period very early in life
Ex. goslings accepting any large moving object as their mother
What is classical conditioning?
Classical conditioning - the most well-
known example of classical conditioning
are Pavlov’s dogs. Dogs naturally
salivate when presented with food. This
salivation caused by food is called the
unconditioned response which is an
innate reflex, and the food stimulus is
the unconditioned stimulus. Pavlov then
rings a bell when food is presented, and
after some time, the dogs associated
the bell sound with the food stimulus.
However, ringing a bell with no food
during the beginning of the experiment
will not cause any response in the dog
because the bell sound was still a
neutral stimulus. At the end though, the
dogs ended up salivating just at the
sound of the bell without needing the
food/unconditioned stimulus. Thus, the
bell sound became the conditioned
stimulus that will elicit a response even
in the absence of the unconditioned
stimulus. The salivation caused by the
conditioned stimulus is called the
conditioned response/reflex.
What is operant conditioning?
a type of learning in which behavior is strengthened if followed by a reinforcer or diminished if followed by a punisher
Positive punishment - adding
something bad to decrease a
behavior (e.g. hitting an animal
when it bites someone)
ii. Negative punishment - taking away
something good to decrease a
behavior (e.g. not giving treats to an
animal when it does not follow
orders)
iii. Positive reinforcement - adding
something good to increase a
behavior (e.g. giving treats to a dog
when it follows orders)
iv. Negative reinforcement - takign away something bad to increase a behaviour (e.g., taking off electric shock collar of dog when it follows orders)
learned behaviour can be reversed in the absence of reinforcement
extinction
the recovery of a conditioned response to a conditioned stimulus after a previously extinguished response is called
spontaneous recovery
What is spatial learning?
decreasing responsiveness with repeated stimulation
habituation
What is insight?
When an organism responds to stimuli similar to the original stimulus but not identical to the original conditioned stimulus
stimulus generalization
an undirected change in speed of an animal’s movement in response to a stimulus (ex. animals scurrying when a rock is lifted) (RANDOM)
kinesis
an increase in behavioral response after exposure to a stimulus
sensitization
a directed movement in response to a stimulus, either toward or away from a stimulus (DIRECTIONAL)
taxis
long-distance seasonal movement of animals
migration
How do animals communicate?
- Chemical - phermones
- Visual - aggression (animal showing teeth) or courtship (peacock displaying feathers)
- Auditory - sounds
- Tactile - touch - bonding, infant care, grooming, mating
This is the ability of the learning organism to differentially respond to slightly different stimuli; animal responds to sounds in 990 to 1010 hz range
stimulus discrimination
What is pecking order?
Social hierarchy or dominance of birds
What is agnostic behaviour?
the active possession and defence of territory to ensure adequate food and place to mate
territoriality
unselfish behaviour that reduces the fitness of an individual (ex. animal risks its safety in denfese of another)
altruistic behaviour
What is kin selection?
the process by which evolution selects for individuals who cooperate with their relatives
(Ex. squirrel sounds alarm when predator comes, detrimental to him but saves family members)
What is reciprocal altruism?
unrelated members of same species help eachother
What is Hamilton’s rule?
rB>C
Appeasement behaviour
one male mating with one female
monogamy
one male mating with multiple females or one female mating with multiple males
polygamy
What is game theory?
reproduction in which an organism produces all of its offspring in a single event, survival rate of offspring is low but there are higher number offspring
semelparity (big-bang reproduction)
produce offspring repeatedly
iteroparity (repeated reproduction)
this is the zone in water where light penetrates and photosynthesis occurs
photic zone
this is the zone in water where almost no light penetration exists, only animals and heterotrophs
aphotic zone
non-living factors such as temperature, climate, light, water availability and topography
abiotic
living things
biotic
a group of individuals of the same species living in the same area
population
a group of populations living in the same area
community
interrelationships between organisms in a community and their physical environment
ecosystem
combination of all the ecosystems on earth; atmosphere, hydrosphere, lithosphere and geosphere
biosphere
place where an organism lives, all other organisms present, and their physical and chemical environments
habitat
all the biotic and abiotic resources in the environment used by an organism
niche
N, or total number of individuals in a population
size
the total number of individuals per area or volume occupied
density
describes how individuals in a population are distributed
dispersion
Describe the survivorship curve
Type I
- survive to middle age but mortality increases in old age
- humans
Type II
- probability of survival is constant and independent of age
- birds, hydra
Type III
- most individuals die young, with few surviving to reproduce and beyond
- trees, oysters
the maximum number of individuals of a population that can be sustained by a habitat
carrying capacity
The maximum rate at which a population could increase under ideal conditions
Biotic potential
elements that prevent a population from reaching full biotic potential
limiting factors
the description of the abundance of individuals of each age
age structure
the description of the abundance of individuals of each age
age structure
What is a K-selected species?
- low reproductive rates
- longer maturation times
- size is constant
- strong parental care
- usually type I survivor curves
Ex. humans
What is an r-selected species?
- high reproductive rates
- shorter maturation times
- weak parental care
- usually type III survivor curve
Ex. insects that invade a habitat and reproduce
Describe the bacterial growth phases
Lag - adapting to growth conditions
Exponential - exponential growth, doubles with every time period
Stationary - growth rate = death rate
Death - bacteria die
Shannon diversity index
measures the diversity in a community
higher value = more diverse
What is the competitive exclusion principle (Gause’s principle)?
two or more species compete for same resources (or occupy same niche), one is more likely to be successful
two species occupy same niche but pursue different resources, minimizing competition
resource partitionning
kills and eats another animal
true predator
parasite
an insect that lays its eggs on a host, after eggs hatch the larvae consumes hosts tissues
parasitoid
an animal that eats plants
herbivore
animals that eat grasses
grazers
What are the conditions which make habitat favourable?
- Substrate texture
- Soil pH
- Soil water potential
- Light availability
- Crowding
- Pioneer species (r-selected, lichens and mosses)
What is primary succession?
occurs on substrates that have never previously supported living things, such as volcanic islands, lava flows, or rock left behind by retreating glaciers
What is secondary succession?
occurs in habitats where communities were entirely or partially destroyed by damaging events, such as fire, flood, insect devastation, overgrazing, forest clearing, construction, etc
Describe the hydrologic cycle
Hydrologic cycle (water cycle) - The
reservoir are the oceans, air (water
vapor), groundwater, and glaciers.
Evaporation, wind, and precipitation
moves water from the ocean to land.
Assimilation is done by plants absorbing
water from the soil, and by animals
drinking and eating other organisms
(which are mostly water). Release is
done when plants transpire and when
animals and plants decompose
animals that eat leaves
browsers
Describe the carbon cycle
Carbon cycle - carbon is required for
building organic materials. It is the basis
for photosynthesis and respiration. The
reservoirs are atmospheric CO2, fossil
fuels (coal, oil), peat, and durable
organic matter (e.g. cellulose).
Assimilation is done by plants when they
use CO2 in photosynthesis, and by
animals when they consume plants (this
is carbon fixing because the carbon is
reduced from its inorganic form of CO2
to organic compounds). Release of CO2
occurs through respiration,
decomposition, and when organic
material is burned
Describe the nitrogen cycle
Nitrogen cycle - nitrogen is required for
the manufacture of amino acids and
nucleic acids. The reservoirs are
atmospheric nitrogen (N2) and soil
(NH4+, NH3, NO2, NO3). Assimilation
occurs when plants absorb nitrogen as
either NO3-
or NH4+ and when animals
obtain nitrogen by eating plants/
animals.
i. Nitrogen fixation - this is when
atmospheric nitrogen (N2) is
converted into organic nitrogen
(NH4+) through nitrogen-fixing
bacteria in the soil. Nitrogen can
also be fixed by lightning and be
converted into nitrogen oxides
(NOx)
ii. Nitrification - this is when
ammonium (NH4+) is converted to
nitrite (NO2-
) followed by the
conversion of nitrite to nitrate (NO3-
)
by nitrifying bacteria
Release of nitrogen is done by
denitrifying bacteria, which convert
nitrate into atmospheric nitrogen.
Detritivorous bacteria also release
nitrogen by converting organic
compounds back to ammonium
(ammonification). Animals release
nitrogen by excreting ammonium, urea,
or uric acid, and through decay since
nitrogen in the form of ammonia (NH3)
is released from dead tissues
Describe the phosphorous cycle
Phosphorus cycle - phosphorus is
required for manufacturing ATP and all
nucleic acids. Cycles for other minerals
such as calcium and magnesium are
similar to the phosphorous cycle. The
reservoirs for phosphorous are rocks
and ocean sediments because erosion
transfers phosphorous to the water and
soil. Assimilation occurs when plants
absorb inorganic phosphate (PO43-)
from the soil and when animals obtain
organic phosphorus when they eat.
Release of phosphorous occurs when
plants and animals decompose, and
when animals excrete phosphorous in
waste products
Describe the energy pyramid
Primary producers
- autotrophs
- plants, photosynthetic protists, cyanobacteria, chemosynthetic bacteria
Primary consumers
- herbivores (eat primary producers)
Secondary consumers
- primary carnivore (eat primary consumer)
Tertiary consumer
- secondary carnivore, eat secondary consumer
Tropical Rain Forest
- high, stable temperature and humidity
- heavy rainfall
- tall trees
- little light enters
- epiphytes (plants that grow on other plants; vines)
MOST DIVERSE BIOME
Savanna
- tropical grassland
- scattered trees
- high temperatures
- little rainfall
- ungulates, large hooved animals like giraffes and zebras
- Austrailia, Africa
Temperate Grasslands
- less water with uneven seasonal rainfall
- lower temperature then savannah (north american praire)
MOST FERTILE SOIL - grazing mammals
Temperate deciduous forests
- warm summers, cold winters
- moderate precipitation
- many animals and plants depending on which part of the forest
- deciduous trees shed leaves
Temperate coniferous
- cold and dry
- vegetation adapted to conserve water (needle leeves)
- warmer than taiga
Desert
- hot and dry
- most extreme temperature fluctuations
- rare rain
- water conservation (cacti)
Taiga
- coniferous forest
- spruce, fir, pine
- long, cold winters
- low precipitation in form of heavy snow
LARGEST TERRESTRIAL BIOME
Tundra
- cold winters, ground freezes
- minimal vegetation such as moss, lichen, shrubs, grasses
- no trees
- deeper soil is permafrost
- little rain
Chaparral
- along California coastline
- wet winter, dry summer
- scattered vegetation
- fires happen here
Polar
- frozen with no vegetation or terrestrial animals
ponds, lakes, streams, rivers
fresh water
largest biome covering 3/4 of earth surface
marine biome
Describe the parts of the marine biome
Benthic zone - this is the lowest
layer of a body of water, including
the sediment surface and sub-
surface layers. In deep ocean water,light does not penetrate. Most
organisms here are scavengers
and detritivores.
ii. Pelagic zone - the water that is
neither close to shore nor close to
the very bottom. This zone is
broken down from top to bottom
in layers:
(i) Epiplagic - this is the surface
layer of water and the only
photic zone since there is
enough light for penetration.
Nearly all primary production
of the ocean occurs here
(ii) Mesoplagic - an aphotic zone,
so there is not enough light
for photosynthesis. There is
minimal oxygen here
(iii) Bathypelagic - aphotic zone
and pitch black. There is no
plant life, and most organisms
here consume detritus that
comes down from above
(iv) Abyssopelagic - also an
aphotic zone. It is cold, high
pressure, and most species
have no eyes due to the lack
of light
(v) Hadopelagic - most life here
exists in hydrothermal vents.
This zone is aphotic as well
overgrazing of grasslands turns grasslands into deserts
desertification
destruction of forests
deforestation
burning of fossil fuels releases SO2 and NO2 into the air and when they react with water vapour, sulfuric acid and nitric acid are created and rains back on earth
acid rain
endangered species
in danger of extinction
threatened species
will become endangered soon
small area with a large number of endangered and threatened species
biological hotspot
bioremediation
using organisms to detoxify polluted ecosystem
biological augmentation
using organisms to add essential materials to a degraded ecosystem
biological augmentation
using organisms to add essential materials to a degraded ecosystem
What is a rainshadow?
a region having little rainfall because it is sheltered from prevailing rain-bearing winds by a range of hills.
