Bio Final Flashcards
(93 cards)
1
Q
What are Tinbergen’s 4 Qs?
A
Proximate:
- Mechanistic development, how do the neurel networks allow this behaviour to occur
- Developmental origin, how is the behaviour aquired over one’s lifetime
Ultimate:
- Adaptive development, how does the behaviour improve chances of survival
- Evolution origin, when and where did the behaviour arise from
2
Q
What did Tinbergen do?
A
Ran an experiment that demonstrated that some animals use landmarks to navigate themselves (done with wasps)
3
Q
What is imprinting?
A
- A type of pre-programmed learning in young animals during critical (sensitive) period of development
- Behaviour develops in response to environmental stimuli
Can have either:
filial (attachment to parent)
or
habitat (attachment to location)
or
sexual (attachment to mate)
4
Q
Describe Fixed Action Patterns (FAP)
A
- Motor response that is initiated by an environmental
stimulus (i.e., key stimulus / releaser) - Must be fully completed
- Sequence of events unalterable
- Innate (not learned)
- Can be triggered under inappropriate circumstances
- Remarkably similar among members of a species (i.e., is highly
stereotyped)
5
Q
What did Karl Von Frisch do?
A
Deciphered the language of bee dances, also discovered that they see UV rays, not red
6
Q
Describe non-associative learning
A
Learning in absence of outcomes
- Habituation, a stimuli is presented and behaviour decreases
- Sensitization, stimuli are presented, behaviour increases
7
Q
What is the difference between operant and classical conditioning?
A
Classical:
- Innate behaviours are learned to be elicited by novel stimuli
Operant:
- A behaviour is
modified over time through association of an outcome
8
Q
What are the 4 terms for classical conditioning?
A
- Unconditional stimulus, elicits innate respones
- Unconditional response, innate reaction
- Conditioned stimulus, novel stimuli assigned novel meaning
- Conditioned response, innate response triggered by CS
9
Q
What is the difference between positive and negative operant conditioning?
A
Positive:
- Stimulus is delivered after change in behaviour
Negative:
- Stimulus is presented and remains until behaviour decreases
10
Q
How can hormones affect reproduction rates?
A
Not producing sex hormones (testosterone) causes some animals to terminate courtship behaviours
Note: When only one male is present all females become reproductively active, but when the male faces competition the number reduces
11
Q
What is the difference between dispersal and migration?
A
Dispersion:
- Permanent movement to new location
- Based on habitat quality, mating competition/seeking and if the place is a reliable breeding ground
Migration:
- Regular movements between two different locations
- Kinesis is random migration patterns
- Taxis is migration patterns directed by stimuli
12
Q
What are navigation methods utilised by migrating animals?
A
- Orientation, using sun, star and geomagnetic compasses to follow directions (N,S,E,W)
- Navigation – determining position in relation to a
particular location (if straying)
13
Q
What is the difference between a signal and a cue?
A
Signal:
- Communicated evolved trait that
is selected for its effect on
the behaviour of the recipient
Cue:
- Consistent aspects of the
environment that can guide
behaviour of individual in way that
enhances its fitness
14
Q
What are channels and what are the four types?
A
Audio, visual, electrical or chemical communication methods than link the sender to the receiver
- Mutualistic (both benefit from the communication)
- Manipulation (sender benefits, receiver is detrimented)
- Altruistic (sender is detrimented, receiver benefits)
- Spiteful (both are detrimented)
15
Q
Describe ritualisation
A
The alteration of a behaviour in ways that reduces the chances of it being misunderstood by recipients.
- Done by:
1. Increasing the conspicuousness of the behaviour
2. Reducing the amount of variation in the behaviour
3. Increasing its separation from the behaviour’s original function
16
Q
What is allogrooming?
A
In social animal groups it refers to the tactile grooming for beneficial purposes such as hygiene or conflict resolution
17
Q
What are eusocial organisms?
A
Colonial, multigenerational organisms with extreme cooperative brood care (often involves sterile worker castes)
E.G Ant colonies
Note: The first step for the evolution of eusocial behaviour is
MONOGAMY
18
Q
What are the three types of altruistic behaviours?
A
- By-products benefits – acts in which both actor and recipients benefit
immediately (note: this isn’t actually altruism because actor benefits) - Reciprocity – altruistic acts that benefit recipients today, with
expectation that actor will repaid in future - Kin selection – altruism aimed at close relatives, selected for because
close relatives are genetically related to actor
19
Q
What is reciprocity?
A
trading of altruistic acts
between two individuals (mutualism with delayed benefit), over time, both participants should experience NET GAINS in fitness.
20
Q
What is Hamilton’s rule?
A
- An altruistic allele will spread if the ‘weighted’ benefit to the recipient is greater than the cost to the actor
Br - C > 0
B = Benefit to recipient
r = Amount of relatedness to actor (Offspring are 0.5, GC 0.25, GGC 0.125 etc)
C = Cost to actor
21
Q
What is the difference between range and geographic range?
A
Range:
- Area over which population occurs
Geographic range:
- Area in which all populations of a species reside
22
Q
Know these:
A
Population size – number of individuals in the total population
Population abundance – number of individuals in a given area
(abundances can vary across the range). Impacted by how INDIVIDUALS are spatially distributed WITHIN a population
Metapopulation – a collection of subpopulations that are exchanging genetic
information (they are connected by gene flow)
Note:
- Emigration and immigration between subpopulations RARE
- Intervening habitat (called the habitat matrix) is a BARRIER to dispersal
23
Q
What are the three types of distribution?
A
Random - random
Uniform - evenly spaced
Clumped - in clumps
24
Q
Name two sampling methods
A
- Using quadrats on a map, find the population in 4/16, 1/4 etc and multiply that for each quadrat
- Using mark-recapture method
25
Describe the mark-recapture method
Collecting a portion of a population, tag them. Later on recollect a portion of the population and see how many of them are tagged from the previous recapture. Use the equation below to determine density:
𝑁 / 𝑀 = 𝑛 / 𝑅
N = population size (not known)
M = # individuals marked
n = # of individuals that are recaptured
R = # of recaptured (n) that are marked
26
What are the four conditions for a stable metapopulation?
1. Suitable habitat occurs in discrete patches that may be
occupied by local breeding populations
2. Even the largest populations must have a substantial risk of local extinction
3. Habitat patches must not be too isolated to prevent recolonization after local extinction
4. The dynamics of the local populations are not synchronized (or the entire metapopulation could go extinct)
27
How do you calculate population growth in an unlimited environment?
28
How do you calculate population growth in an isolated environment?
The exact same as unlimited however without the amount of immagrant and emmigrants. So:
N(t+1) = Nt + Bt - Dt
29
How do you calculate population growth rate?
!!!!!∆N/∆t!!!!!! = N(t+1) - N1 = Bt - Dt
30
What are the two types of growth in closed systems?
1. Exponential growth (density independent)
- Growth rate does NOT depend on number of individuals
- Usually occurs when species colonize new habitats or
recolonize a habitat
2. Logistic growth (density dependent)
- Growth rate DOES depend on number of individuals
- Most populations show this type of growth
31
How do you calculate population growth rate per capita?
∆𝑁 / ∆t = ((B/N) − (D/N)) N
Note: r = b - d so
∆𝑁 / ∆t = rN
r represents the intrinsic growth rate
higher r = faster growth
32
How do you estimate future population sizes in exponential growth?
33
What is Carrying capacity (K)?
Maximum number of individuals in a population that can be supported by that population
34
What are some tradeoffs in traits?
1. How long you grow before reproduction
2. Early versus late maturity
3. Having few large versus many small offspring
35
What is the difference between r and k strategy types?
- An R-strategist allocates many resources to reproduction.
E.G Dandellions which grow, spend a ton of energy to make and release gametes and then disappear.
- Things that reach their carrying capacity and require low resource allocation for reproduction are K-Strategists
36
Describe opportunistic and equilibrial life histories
- Opportunistic life history – individuals with high fecundity, grow quickly, reach sexual maturity at early age, produce many/small offspring (i.e., r-strategists)
- Equilibria individuals with high survivorship, grow slowly, invest more energy into protection/survival/acquiring
resources, reach sexual maturity later and have few/large
offspring (i.e., k-strategists)
37
What are the two types of niches?
- Fundamental niche: Full range of climatic conditions and food resources that permits a species to survive (absence of interactions with other species)
- Realized niche: Species niche in the presence of negative species
interactions (interspecific competition or predation),
38
What is phylogenetic niche conservatism?
Similarity in aspects of the niches
of closely related species due to their shared evolutionary history
E.G Woodpeckers which all have the same physical adaptions through evolution and thus live in similar niches
39
What are the two types of competition?
1. Exploitation (resource competition) – when one competitor consumes a shared resource that limits its and other species’
growth, making it less available for others to use (two
competitors only interact indirectly)
2. Interference (contest competition) – when one species
restricts another species’ access to a limiting resource, which
can involve antagonistic interactions or one species excluding the other from a space (two competitors directly interact)
40
What is the R rule?
When two species compete for a single limiting resource (at constant population densities) the species that can persist on lower amounts of that resource will
win the competition.
41
What is Amensalism?
When one species is not affected by competition (it ‘wins’ outright), e.g., kudzu
42
What is Predator-mediated coexistence?
Predation can reduce number of
dominant competitors, leading to coexistence with lesser
competitors it would otherwise exclude
43
What is character displacement?
Divergence in characteristics
of two otherwise similar species as a result of competition in sympatry (changes due to effects of NS!)
E.G Darwins finches with different beak shapes so they can target different resources (big vs small seeds)
44
What is obligate mutualism?
A form of mutualism where one of the species cannot survive without the benefits of the other
45
Describe commensalism
Interspecies relationship in which one species benefits and the other is neither positively or negatively impacted
46
What are Trophic cascades?
When the rate of consumption at one trophic level results in a change of species abundance /
composition at lower trophic levels (causes a cascade)
E.G Owls consumption rate of snakes decreases the snake population which allows the mice pop. to grow
47
What is trophic facilitation?
When a consumer is indirectly helped by a positive interaction between its prey and another species
48
What are the four species types?
- Dominant species:
Species that have a large effect on a community because it is more numerous or has the
highest biomass within that community
- Keystone species:
Species that affect other members of community in ways that are disproportionate to its
abundance / biomass
- Ecosystem engineers:
Species that actively shape their
physical environment in ways that create habitat for for
other species
- Foundational species:
Species that provide structural
habitat for other species
49
What are three things that impact biodiversity
Habitat heterogeneity:
- Environments with more spatial heterogeneity have more
microhabitats/microclimates à can support more species
Climate variation:
- Stable climates typically have higher biodiversity levels
than climates with predictable or unpredictable
variations
- Predictable changes (e.g., seasonality) can increase
biodiversity of area through temporal niche partitioning
Disturbances:
- Frequent and rare disturbances will favour good colonizers
- Intermediate levels of disturbance might favour neither,
and both types of species can persist in area
50
Describe intermediate disturbance hypothesis
– Communities that experience
intermediate levels of disturbance will have a higher species richness because more coexistence is possible.
51
What does community succession mean?
Following appearance of new habitat, or disturbance that
removes species, a community will undergo predictable sequence of changes
- Pioneer species:
Early colonizers that persist in a community based on their ability to colonize/recolonize after disturbances (opportunistic species)
- Climax community:
Final stage of succession, mature assembly of best competitors (equilibrial species)
52
What is the difference between primary and secondary succession?
Primary:
- Colonisation following a disturbance that eliminated ALL species in the area
Secondary:
- Recolonization following a disturbance that only
partially removed species from area
53
Know this
54
What two factors determine the number of species that an island can support?
1. Size of island, due to capacity and colonization rates
2. The distance to the nearest source of colonists, high colonization rates and rescue effect
55
What is the rescue effect?
Extinction rates are
mostly a function of
island size not distance,
but new arrivals of the
same species can prevent
its disappearance
56
What is the difference between food chains and webs?
Food chains:
- transfer of energy and nutrients through trophic levels, each species exists only at one trophic
level in chain
Food webs:
- transfer of E and nutrients through ALL trophic levels, species can exist in several trophic levels at the same time
Note:
Trophic level – the position of an organism within a food web or chain based on what level it feeds at, ranges from 1 (primary producers) to 5 (apex predators).
57
Describe trophic transfer efficiency
Measurement of the amount of energy available at one level that makes it into the next trophic level (measures how efficient the transfer of E is), often measured by biomass (E proxy)
production at trophic level n
= --------------------------------------------
production at trophic level n-1
58
What is a trophic period?
Relative amounts of energy or biomass in each trophic level
59
What controls the rate of photosynthesis?
- Liebig’s Law of the Minimum: primary production is limited by the nutrient that is LEAST available
- If one growth factor or nutrient is deficient, this is what limits photosynthesis & plant growth
60
What are the limitted nutrients for forests, open oceans, and coastal marine ecosystems?
Forests - N limited
Open oceans - P (and N) limited
Coastal marine ecosystems - Fe (iron) limited
61
Explain day lengths based on globe position
All parts of the earth recieve the same amount of average light per year, just with different distributions. As you get closer to the equator the light levels / day lengths annually stay fairly consistent, whereas far away there is long days short nights or vice-versa
Note: The southern hemisphere experiences summer solstice in Dec, and winter solstice in June!
62
What is equinox?
The period where the earths rotation runs parallel to the sun and days and nights are both approx. 12 hours
63
Know this
64
What is insolation?
The amount of solar radiation reaching a given area of the
earth, often measured as energy per unit area, or energy per unit time
65
What is the Intertropical Convergence Zone (ITCZ)?
Around the equator it is an area that's known by sailors as the doldrums or the calms because of its monotonous windless weather, is the area where the northeast and the southeast trade winds converge
66
What are hadley cells?
67
How are deserts formed?
Zones of subsidence
within Hadley cells create
deserts because this
descending air absorbs
water from the earth.
68
What are the three sets of circulation patterns?
- Trade Winds (Hadley cells):
surface winds in tropics, driven by uplift within ITCZ, blow E --> W, meet at ITCZ
- Easterlies (Polar cells):
Surface winds in polar regions, driven by subsidence near poles, blow E --> W
- Westerlies (Ferrell cells):
Surface winds driven by cells to either side of them, blow mid-latitudes W --> E
69
Describe the coriolis effect
- Winds appear to deflect due
to rotation of Earth
- Because earth is rotating,
observers on surface of
planet would observe winds
(and waters) bend instead at equator
(SH = Left, NH = Right)
Note: Hurricanes in NH spin right, left in SH
70
What are ocean gyres?
Large circulating ocean currents, driven by the movement of surface
winds, which are themselves driven by variations in insolation and the Coriolis
71
What is thermohaline?
How temperature and salt conc. affect density
- Hot water is less dense than cold water
- Salt water is more dense than fresh water
72
What are biomes and terrestrial biomes?
Biomes:
- Broad, ecologically uniform area whose characteristic species reflect regional climate (desert, tundra)
Terrestrial biome:
- Large-scale terrestrial communities defined by dominant vegetation type whose
distribution is largely based on ABIOTIC conditions (e.g., climate and soil)
73
What is upwelling?
It is the flow of cold and nutrient-rich water from deeper waters to the surface. Occurs where prevailing winds blow parallel to coastline, pushing surface waters away from coast
74
What are lotic systems?
When water in rivers or streams move in one direction, with and up and downstream.
Note:
Fast moving, cold water has more oxygen than slower systems
75
What are lentic systems?
When water in bodies of water are stagnant / still
76
How are lakes divided into water levels?
77
How are oceans divided into water levels?
78
What is the global biogeochemical cycle?
Linked network of biological
and physical processes that moves nutrients through pools
within the environment
Note:
Pool = large reservoir of nutrients
Flux = movement of nutrients between pools
79
What are the types of biogeochemical cycles?
1. Hydrological cycle:
Water --> Cloud --> Rain --> Rivers --> Water
2. Carbon cycle:
Photosynthesisers help reduce carbon from air, release it when they die. Human activity generates carbon. (highest in early
spring / lowest in early fall)
80
What are three reasons carbon dioxide levels have been increasing?
1. Geological inputs (volcanoes, mid-ocean ridges)
2. Biological inputs (respiration)
3. Anthropogenic inputs (burning fossil fuels, deforestation)
81
How does the nitrogen cycle work?
1. Nitrification:
A process in which NH3 or NO2- are oxidized to generate energy
NH4 --> NO2 --> NO3
2. Denitrification:
A form of anaerobic respiration
in which NO3- is terminal
electron acceptor
NO3 --> N2
3. Nitrogen fixation:
Process by which some bacteria and archaea reduce N2 gas to biologically useful NH3
82
WHY DO N-FIXERS ‘FIX’ NITROGEN?
Chemoautotrophic bacteria and arachaeons use NO3- or NH3 to
generate energy, releasing N2 gas as biproduct. This causes biologically useful forms of nitrogen to decrease in the soil. To obtain more, nitrogen fixers convert N2 gas into more NO3- or NH3
83
What are rhizospheres?
Soil layer surrounding actively growing roots, receives
carbohydrates from plants to stimulate growth of soil microbial
mutualists.
84
How can symbiotic relationships exchange carbon for nitrogen?
1. Rhizobium bacteria:
Nitrogen-fixers that exchange organicallyuseful forms of N for carbohydrates
- Insert themselves into the root nodules
2. Ectomycorrhizae:
Fungi that exchange water and nitrogen (obtained from soil) for carbohydrates
- Surround roots with a thin layer of fungal cells
85
Why form relationships with mycorrhizae?
- Fungi can decompose organic matter to obtain nitrogen
- Their hyphae are extensive, allowing them to reach more soil to extrapolate nutrients from
86
How does the phosphorus cycle work?
87
What do plants do to help them obtain phosphorus?
They form mutalistic symbiotic relationships with endomycorrhizae.
These are fungi that penetrate root cells and form highly branched arbuscules that grow inside roots
Plants can trade carbon for phosphorus
88
How many climate driven extinction events have occurred in history and why?
5 have occurred
Direct causes:
- Rapid temperature changes (often linked to changes in atmospheric CO2 levels)
- Changes in sea level (melting / formation of continental ice sheets)
Indirect causes:
- Drivers such as asteroid impacts, volcanic eruptions, etc. impact climate system
- This then triggers rapid temperature and sea level changes
89
What impact did humans have on megafaunal populations?
Around 50,000 years ago megafauna roamed the earth. As human populations increased, so did hunting. This hunting caused the extinction of many of these species.
I mean that gigantic sloth would be such an easy target. Easy to find, slow, passive thus easy to kill. Could single-handedly feed a whole village.
90
What is the neolithic revolution and what were its impacts on ecosystems?
The emergence of agriculture,
domestication of plants and animals, shift in human settlement patterns. irrigation changed
waterways, clearing of forests released C to atmosphere, domestication of plants and animals fundamentally changed their evolutionary paths
91
What is the interval of time where human activities dominate
key processes on earth and impact biodiversity on a global scale?
Anthropocene
E.G Electricity, Steam engines
92
How and why are trees shifting?
Trees are shifting both west
and north as well as upslope in USA to account for precipitation changes caused by climate change
93
What is the United Nations Framework Convention on Climate Change
(UNFCCC)?
- Ultimate goal: “stabilize greenhouse gas concentrations in
the atmosphere... at a level that would avoid dangerous
anthropogenic interference with the climate system.”
- Two key treaties
o Kyoto Protocol – 1997
o Paris Agreement – 2015
