Final Exam Flashcards
Define ecology and provide the name of the individual who originally coined the term
the study of the relationships between organisms and their environment; Ernst Haeckel
Define and distinguish between a population and community
Population= all members of a species in a given area Community= all populations interacting within an ecosystem
Climate change is certainly going to impact large-scale ecological patterns. Explain how an organisms use of a microclimate might be able to lessen the impacts.
microclimates are the local conditions that an organism can live in. These often do not match the climate profile, so if the climate as a whole is experiencing an impact, the small microclimate may not be affected.
What is a biome and what are the 2 most important environmental variables that determine them?
biome= broad-scale region dominated by similar types of ecosystems; temperature and rainfall
What is a model? Provide your own 3 factor model for your grade in this class
Model= abstract, simplified representation of real systems;
Final grade= study hours + intelligence + attention
President Trump tweeted this: “It’s snowing and freezing in NYC. What the hell ever happened to global warming?” Why is this wrong?
weather is not climate
Explain the greenhouse effect in moderate detail
process by which radiation from the planet’s atmosphere warms the planet’s surface temperature above what it would be without an atmosphere. Greenhouse gases trap the radiation and radiate it back to earth. Earth receives 2x longwave radiation from atmosphere compared to shortwave radiation from sun.
What is the difference between relative and absolute humidity?
Relative humidity= amount of water in a given volume of air expressed as a % of the saturation vapor pressure
Absolute humidity= amount of water in a given volume of air
Draw and label a stratified lake showing the three regions
- epilimnion (top of lake)
- metalimnion (middle layer)
- hypolimnion (bottom layer)
Why are intertidal zones called the “environment of the extreme?”
- major shifts in abiotic environment
- saltwater or none
- change in temps
- change in predators and prey
Describe 3 known effects of climate change
- ice cap melting (arctic shrinking and antarctic growing)
- thermal expansion (raising water levels)
- frost-free seasons (lengthening of seasons)
Explain what a rainshadow is and how it works
see pic
What is an emergent property and how are food webs a good example of one?
Emergent property= something greater than it’s parts; it’s difficult to predict the relationships between species as well as impact upon removal of one part.
Explain a trophic cascade. Why are keystone species often involved?
Removal of the top predator causes a cascade of changes in species that reside beneath it. Can cause and increase/decrease in populations as well as changes to the ecosystem itself.
What is the water cycle? use the terms precipitation, interception, infiltration, and surface runoff in your answer.
The continual process by which water travels from the air to the earth’s surface, and back again. Precipitation= return of water form the atmosphere to the surface
Interception= the process of water NOT reaching the soil
Infiltration= water that reaches the soil surface
Surface runoff= occurs when soils are saturated and water flows across the soil surface
Given what you know about the water cycle, why does the removal of a large tree cause more damage to an ecosystem than just its physical removal?
Trees take place in transpiration, which filters water at a pace faster than any human machine. Removal of a tree is removal of a water filter that can remove harmful chemicals.
The physical properties of water are significantly impactful to life on Earth. Describe 3 of the physical properties of water that we discussed.
- water is polar (generates hydrogen bonds)
- cohesion (tendency of a substance to stick to itself, resisting external forces)
- water is highly dense (buoyancy)
What is meant by the terms target of selection and selective agent? Briefly describe the 3 different types of natural selection that accompany these terms.
Target of selection= the phenotypic trait that selection acts directly upon
Selective agent= environmental cause of the fitness difference among organisms with different phenotypes
-disruptive, directional, stabilizing
There are 5 processes that can drive evolution. What are they and briefly describe them.
- Natural selection
- mutation
- genetic drift= change in allele frequency due to random chance
- migration=movement of individuals into or out of a local population
- non-random mating
There are different types of isolating mechanisms for reproduction between species. What are 2 pe- and post-zygotic barriers to reproduction? Briefly explain them.
Pre-zygotic:
-temporal isolation: different breeding time
-habitat isolation: live in different habitats
Post zygotic:
-hybrid inviability: not viable (dies)
-hybrid sterility (cannot pass genees on to next gen)
Expalin the theory of island biogeography. Why is it called equilibrium theory? What two relationships does it combine? draw figure explaining it
Theory of Island biogeography used to predict number of species on an island which reflects the balance of colonization and extinction. Rates of colonization and extinction depend largely on island size and distance from mainland
- species-area relationship
- species-isolation relationship
In general, there are 2 modes of speciation. Name and define them. Which one is more likely to create a new species?
Allopatric= population is separated by geographic boundary
Sympatric=result of divergence in diet, habitat, or both. no barrier
allopatric more common
Name and describe 3 different biomes with moderate detail
-Tropical rainforests: warm and constant temps, daily rainfall, trees dominate, high biodiversity, 6% of earth’s surface
-Deserts: 15% of surface, less than 10 in of rainfall, dry, hot or cold, scattered shrubs
Temperate forests: deciduous trees, year round precipitation, seasonal temps, mainly see secondary forests today
Define natural selection. Describe the 4 tenants of natural selection
Natural selection= the differential success of individuals within a population that results form interactions with their environment Tenants: -competition -variability -inheritance -adaptations
What is the intermediate disturbance hypothesis?
disturbance in an ecosystem continually disrupts interspecific competition; local diversity is maximized when disturbance is not rare nor too frequent
Using the figure, explain which population has niche conservatism and niche evolution. What are those terms and how can you tell?
Niche conservatism= closely related species maintaining ecologically similar traits
Niche evolution= divergence in ecological traits
Biogeography often tries to resolve how any given species arrived at their current geographic distribution. They use the concept of endemism, disjunct populations, vicarriance, and dispersal to create a cladograms. Define these terms
Endemism= restriction of species to a particular area
Disjunct populations= occurrence in different areas with gaps in between
Vicariance= fragmentation of ancestral distribution by formation of geographic barriers
Dispersal= migration of organisms across pre-existing barriers
Define alpha and beta diversity. Label it on graphs
Alpha diversity= number of species in a community or habitat
Beta diversity= difference/change in species number along an environmental gradient
We are currently in our 6th mass extinction event. What evidence is being used to declare this?
The current rate of extinction is significantly higher than the background rate
Explain the terms phenotypic plasticity and reaction norm.
Phenotypic plasticity= the ability of a genotype to give rise to different phenotypic expressions under different environmental conditions
Reaction norm= the set of phenotypes expressed by a single genotype across a range of environmental conditions
What is a cline? What is a ring species? Are they the same?
Cline= measurable, gradual change in a population along an environmental gradient
Ring species= connected series of neighboring populations which can interbreed, but the two end populations cannot
Compare and contrast the terms: trade-off and constraint
Trade-off: increased ability in one task often results in a decreased ability in another
Constraint: limitations imposed on an organism due to their adaptations to their local environment
Why are the side-blotched lizard males a great example of an “evolutionary stable strategy”?
they all balance ea. other out. One is stronger than the other. Another pretends to be female. Another can defeat the other.
Explain at least 3 general causes of species declines
- habitat loss, modification and fragmentation
- Pollution and disease
- exotic Species introduction
What are the 2 fundamental limitations placed on animals due to their size?
- gravitational limits
- getting enough fuel (O2)
An animal’s shape can have an impact on what they are capable of. Given this, what is Carrier’’s constraint? Which general animal is he talking about?
Movement of limbs compresses the ribs, making it impossible to breathe and walk at the same time. This is seen in lizards
Explain the terms endotherm, ectotherm, poikilotherm and homeotherm
Endotherm= gets heat from metabolism (internally) Ectotherm= gains heat from external sources Poikilotherm= wide range of body temperatures Homeotherm= maintains a constant temp
What is the energy balance equation?
describes all the ways in which an organism may gain thermal energy
Qabs+M+R+C+LE+G= heat energy gained
In your own words, define what life history is
the pattern of reproduction and survival factors within an organisms life that affects it’s success
If body parts are growing differently than uniform 1:1 ratio, what is that phenomenon called?
allometry (allometric scaling)
Organisms often invest different amounts into their reproductive effort and this ultimately affects their fecundity. Given this, the example in class looked at the European Kestrel. Why does it typically only have 5 offspring?
- any higher= more time flying and looking for food –> mortality increase; brood grew slower and had higher mortality rate.
- any lower –> decrease in chance of fitness
Animals have many different ways of acquiring oxygen. Briefly describe 4 and what lineage it belongs too
- gills– aquatic vertebrates
- gulping to force air into lungs– amphibians
- hepatic-piston pump– crocs
- retention of air into multiple air sacs– aves (birds)
- ribs and diaphragm–mammals
There are currently 3 hypotheses that may explain how metabolism scales with body size. Briefly explain each.
- surface area to volume– metabolism scales with mass 2/3
- Kleiber’s Law– metabolism scales with mass 3/4
- curvilinear fit
What is a conformer? What is a regulator? What is a benefit/drawback of being either of these?
Conformer= unable to maintain consistent internal conditions pro= doesn't use as much energy con= relies on environment for heat Regulator= variety of mechanisms to regulate internal conditions pro= can produce heat from within; doesn't rely on environment con= takes a lot of energy
In many different populations we see differences in fecundity and reproductive effort based on an adult’s likelihood of surviving. What is fecundity and what is reproductive effort?
fecundity= the number of offspring produced per unit time
reproductive effort= the total energetic costs of reproduction per unit time
