Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.



H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

178 Cards in this Set

  • Front
  • Back
What are the 3 levels of biodiversity centrally dependent on species?
1. Genetic- variation within species
2. Species- variety of different species in an area
3. Ecosystem- variety of physical environments and biotic communities over a landscape
How many species are described? Is this a correct estimate?
Currently 1.75 million species described, but it is estimated to be at least 10x more we don't know about
What are parts of the world called that have high biodiversity? Where are they?
these are called hot spots
usually in the tropics
Are species immortal?
No. The fate of every species is extinction. There is always an end to the evolutionary line
Is the current mass extinction at a natural rate?
No. It is exponentially larger than past mass extinctions (5 of them).
What are the components of the evil quartet?
Introduced Species
Habitat loss and degradation
Ecosystem stress
What are the reasons for overkill?
Overexploitation because they are an important resource for us

Deliberate killing because we perceive them to be pests
How do native species contribute to extinction crisis?
Causes ecosystem stress because natives have not evolved ways to live with these exotics and they can destroy unprepared ecosystems
What is the formula for human impact?
I= P x A x T

Human impact = Population x Affluence x Technology
What does all of biodiversity hinge on?
the success and failure of a species
What is biodiversity?
the diversity of life on Earth
What is the hierarchical organization of genetic diversity?
Variation within populations and among other populations
Define what a species is.
What is the ultimate factor for defining a species in the biological species concept?
There must be reproductive isolating mechanisms to separate different species
What is a sub species?
Regionally distant species but can still interbreed
What are the 3 times of speciation?
What is allopatric speciation?
1. a barrier is created between a population separating them
2. Evolution occurs within both populations creating reproductive mechanisms
3. Now genetically distinct species if brought back together
What is parapatric speciation?
1. New niche is created
2. New genetic way of living --> new reproductive isolating mechanisms
3. Can no longer interbreed
What is sympatric speciation?
Mutations occur within the population and the individuals can no longer mate with the original population
What is diversification?
A founder species is introduced to a new area, and many new species arise from the founder by entering new niches
What long does it take for speciation to occur?
Using islands as a model, approximately 10-15k years

very slow process!
What families are not well documented species wise?
virus and bacteria are not well documented because they are hard to study and hard to find
How do todays extinction rates compare to speciation rates?
Extinction rates are rapid in comparison to very slow speciation rates

A rapid net loss of species occurs
What is a native species?
found naturally in a place
What is an exotic specie?
a non-native introduced by human activities
What is an endangered (threatened) species?
At risk of extinction
What is an endemic species?
found only in certain places
What is a flagship species?
can motivate people to protect a place
What is an umbrella species/
if protected , other species accommodated
What is an indicator species?
status reflects condition of ecosystem
What is a keystone species?
many key interactions with other species
What is a biological community?
all the species that occupy a particular area and the interactions among those species
What is an ecosystem?
a biological community with its associated physical and chemical environment
What are ecosystem processes?
water cycles, nutrient cycles, and energy capture
What is ecosystem diversity?
the complexity of the biological community and its interactions wit the environment and ecosystem processes
What are ecosystem services?
the range of benefits provided to people such as clean water and reduction in pllution
Are species considered equal in an ecosystem?
NO, there are different statuses
What is the abundance and impact of a keystone species?
High impact, low abundance
What is the abundance and impact of a dominant species?
High impact, high abundance
What is the abundance and impact of a rare species?
Low impact, low abundance
What is the abundance and impact of a common species?
Low impact, high abundance
What is the richness in the measurement of species diversity?
it is the tally of species in an area
What is evenness in the measurement of species diversity?
Relative abundance of species (is it rare or common?
If Community A has a higher richness than Community B, who has higher biodiversity?
Community A because it has more species
If community A has a higher evenness than community B, who has the higher species diversity?
community A . Can have same number of species (equal richness), but more evenly distributed and no species risk of extinction
What is heterogeneity?
combines richness and evenness
What is the species area relationship?
10x area increase results in 2x more speices
According to the species area relationship, if you got rid of 90% of a habitat, how many species would be lost?
What are the three types of geographical scale of diversity?
What is alpha diversity?
average number of species at sites of similar size and habitat type
What is gamma divhersity?
number of species over a large region encompassing many similar sites

number of species in all the areas total
What is beta diversity
rate of change of species across different sites ( gamma/alpha)
What factors cause geographical differences in species richness?
Environmental gradients
Islands vs continents
Disturbance regimes
What are some environmental gradients that determine species richness?
elevation- go up, fewer species
latitude- equator most, poles least
productivity- more productivity more species
complexity- more complex more species
time- longer been in existence, more species
How are disturbance regimes beneficial?
moderate level of disturbance results in higher species diversity

Allows no species to over run, and allows new species to enter new niches
What are reasons that the rain forest is the most diverse?
High productivity
large geographical area
great long term stability
constant environment
intense species interactions
Is there congruence between taxa for endemic species?
There can be, but not always
What is extinction?
death of the last individual of a specis
Is extinction a natural process?
Yes. Eventually all species become extinct at some point
What are the two types of extinction?
Phyletic extinction
Terminal extinctions
What is a phyletic extinction?
occurs when a species disappears in the process of evolving into one or more new species, but there is no net loss of diversity
What is terminal extinction?
occurs when a species disappears without evolving into new speices. There is a new loss of diversity
What is the process of extinction step wise?
1. Extraordinary change occurs in the species' environment
2. Survival rates, reproductive rates (or both) decline
3. Population size declines
4. The two types of extinction are possible
What is the ultimate and proximate factor of the process of extinction?
Ultimate- extraordinary change in the species' environment

Proximate- survival rates, reproductive rates (or both) decline
What is a deterministic extinction?
occurs when there is no doubt about the eventual outcome- extinction is 100% certain
What is a stochastic extinction?
occurs when there is some uncertainty about the outcome - extinction outcome is less than 100%
What is a possible outcome for stochastic extinction?
population declines can result in sufficient density-dependent compensation to stablize the population at a small size
What is the probability that a species will go extinct if left as a small population?
all up to chance ..good or bad stochasticity
What is environmental stochasticity?
chance changes in the species' environment that are harmful
What is demographic stochasticity?
chance changes in vital rates that are harmful
What is genetic stochasticity?
Chance changes in the species' gene pool that are harmful
What are the 3 outcomes of bad genetic stochasticity?
loss of rare alles- founder effect
loss of heterozygosity- genetic drift
fixation of deleterious alles- inbreeding
What are some traits of a vulnerable to extinction species when the environment changes ?
large body size
top of food chain
restricted geographic range
low intrinsic rate of growth
specialized niche
living in a normally stable environment
How long do species typically last?
1-10 million years without a mass extinction
What is the background rate of extinction?
.00001% - .0001% of species lost a year
What characterizes a mass extinction?
A much higher rate compared to the background extinction rate

particular groups targeted

regional/ global

occurs over a relatively short period of time
What were the 5 mass extinctions of the past?
Which mass extinction was considered the worst and why?

Lost 95% marine life
lost 70% of land life
took over 50 million years to recover
What characterized the Devonian extinction?
Marine organisms primary victims
loss of 30% animal families
Caused by global cooling
What characterized the Permian mass extinction?
worst mass extinction
What characterized the Triassic mass extinction?
opened the door up for dinosaurs
What characterized the Cretaceous mass extinction?
demise of the dinosaurs as the dominant group
What is the current extinction rate?
.01% a year lost
What two factors are the cause of the 6th mass extinction?
Human tool making and cultural evolution

allowed us to become super predators and able to pass on the information
What does the global extinction of species thousands of years ago model?
prehistoric human migration
What types of animals became the majority of extinctions with prehistoric humans?
large herbivores (mega fauna)
How did agriculture change humans relationship with wild species?
domesticated plants and animals and began controlling breeding

began to persecute species that threatened our domesticates which led to threatening predatory species with extinction

also encroached on wild species land
What human activity contributes to the most habitat loss?
What is another negative effect of agriculture after habitat loss?
introduction of exotic species (deliberate and accident)
What are some ecosystem stressors?
What are the big trends of the current mass extinction?
it is increasing at an accelerating pace
most of earth's biota is suffering losses with a lot of species threatened in complex ways
shift from species poor islands to species rich continents
What is the single greatest threat to biodiveristy?
habitat loss
What is overkill?
the deliberate non deliberate killing of a species (valuable or a nuisance) at a pace that it can't reproductively keep up
Why is habitat loss so disastrous?
because of the species area relationship, if we lose 90% of their habitat we lose 50% of the species
What is habitat loss?
occurs when the environment has been so changed that the species can no longer exist there
What is habitat degradation?
the quality of the environment has been changed in ways that severely reduce a species fitness
What are the four major ecosystems of the U.S. that are being depleted?
grassland prairies
old growth forest
tropical forests
What is a major form of habitat degradation?
habitat fragmentation
Which evil quartet member effects species the most?
introduced species
What are the types of overkill?
persecution of species
inadvertent killing
What are some traits of species that are vulnerable to overkill?
high commercial value
international commerce
international range/movements
human prejudice

low rate of growth
What is subsistence exploitation?
local people using the resources for their livelihood
Is subsistence exploitation more or less likely to lead to overexploitation?
it is less likely but it can happen if population densities get too high and technology increase
What is recreational exploitation?
this includes hunting, fish, bird watching and eco tourism
Does recreational exploitation lead to over exploitation?
NO. it is heavily regulated with permits, laws and fines for consequences

What is persecution of pests?
we deliberately kill a species due to our prejudice.

includes predator control
What is a solution for persecution of pests?
education and non lethal control alternatives
What is inadvertent killing?
animals killed while doing something else

(ie- cars, bycatch, etc)
What are some solutions to inadvertent killing?
simple technological solutions can really help

i.e- Turtle excluder devices in shrimp nets
What are the two options for exploitation?
overkill or sustainable harvesting
What is the biological advantage of sustainable harvesting?
when taking out some individuals in a population, the remaining individuals reproduce better and the population grows and the population stabilizes at a reduced size
Which species can be harvested sustainably?
potentially any, but there would be large variation in the yields and potentially not be worth it
How can we regulate over harvesting?
regulating take
regulate effort (permits, season)
regulate harvesting methods
utilize market forces
change culture
What is the benefit for privatizing natural resources?
most likely not going to over exploit their own resource
What is tragedy of the commons?
communally owned resource prone to abuse because the profits go to the exploiter and the costs get pushed onto society
What is CITES?
Convention of International Trade in Endangered Species of Wild Fauna and Flora
Why are island biotas vulnerable to exotics?
they live in isolation and are not adapted to deal with the damage of exotics to the biota environment

also due to the species area relationship the populations are very small
What are the 4 main threats from exotic species?
ecosystem modification
What are some intentional reasons for introducing a new species?
Bio control
game for hunting/fishing
What are some ways exotics accidentally get introduced to a new environment?
pet escapes
What is the case of the native Hawaiian birds and disease?
they have been pushed up to higher elevations where the disease spread from mosquitoes is not present in which to survive, but they will slowly get pushed out because there is no where left to go
What other ecosystems are vulnerable to exotics?
fragmented areas due to habitat loss
isolated lakes, ponds, rivers
mountain tops
What are some problems that plants face with exotics?
herbivorous animals
insect pests
plant diseases
competing plants
Which commensal species is the most widespread and harmful of all exotics
How are cats invasives?
they hunt species (birds, reptiles etc)
become top predator and push out other predators
transmit feline diseases

all of these cause major problems on island ecosystems
What are feral cats unlike natural predators and just fit into the ecosystem?
can exist at high densities
no regulation on population size
subsidized predators
even if well fed they still kill widlife
What is deforestation?
cutting down trees and clearing of forests
usually conversion of forest to something else
What are the direct causes of deforestation?
cattle grazing
fuel wood gathering
commercial logging
What are frontier forests?
world's remaining and intact natural forest ecosystems
What 3 countries have the remaining 70% of frontier forests?
Russia, Brazil and Canada
What is desertification?
ongoing land and soil degradation in arid, semi-arid and semi-humid areas caused by human activities
What are the characteristics of desertification?
brush invasion
groundwater depletion
salinzation of soil
severe erosion
sever loss of biodiversity
What causes desertification?
humans activities- agriculture (short crop rotation) , deforestation, over grazing, overuse

climatic changes - increase temp or precipitation
What is a wetland?
land which is saturated by water at a frequency and duration that allows for the growth of vegetation adapted for saturated soils

How can we provide habitat to species?
protection- set aside

conservation- sustainable

restoration- restore to prior levels of biodiversity
What are ecosystem stressors?
any chemical, physical, or biological factor that can cause adverse effects on individuals, populations, communities or ecosystems
What effect does stress have on an ecosystem?
can absorb certain levels of stress due to their resiliency, but stressed beyond a certain point --> shift to new equilibrium and tend to lose biological diversity
What human activities stress ecosystems?
lose/addition of keystone species
climate change
What is a trophic cascade?
a series of trophic interactions that result in cascading changes in species composition and ecosystem function
What are two causes for trophic cascades?
accidental introductions of exotics or killing of natives (especially keystone species)
Which stressor has the biggest effects on air and water
What is the hierarchial organization of biological systems affected by pollutants?
What is biological magnification?
pollutants/toxins store in the fats of animals at lower trophic levels and the amount of toxins accumulate up the trophic levels, and the top predators are most threatened
What is cultural eutrophication?
nitrates from agriculture runoff go into bodies of water and cause excessive growth of aquatic plants (mostly algae)
leads to oxygen depletion due to the decay --> massive die off of oxygen dependent organisms
How is acid rain formed?
production of nitrous oxide and sulfer dioxide convert to sulfuric acid and nitric acid and acidify soil and water
How are birds affected by acid rain?
the acid rain deplete calcium from the soils which killed off snails. birds rely on snails for calcium and as a consequence their egg shells became thinner
How should we respond to ecosystem stress from pollution?
gov. should control pollution
polluters who treat it as externality should pay some price
adopt lifestyles that produce less pollution and waste
Which greenhouse gas constitutes 76% of all the greenhouse gases?
Carbon dioxide- caused by fossil fuel burning and forest burning
What is the problem with methane in comparison to carbon dioxide?
only constitutes 13% of total greenhouse gas, but is 30x better more effective at trapping heat
Is the warming of the earth uniform?
No some places are more effected than others
Which climates are most effected by climate change?
arid lands
arctic ecosystems
high altitude ecosystems
low lying coastal regions
coral reefs
What are two reasons some organisms won't be able to adapt to climate change?
Have no suitable habitat left
unable to reach places with suitable habitat
What are the four ways species can respond to climate change
acclimatize- change morphology, behaviorally or physiologically, during their lifetimes

adapt- evolve new traits
disperse- shift habitats
What are some potential effects of climate change?
latitude/elevation shifts
shifts in timing of yearly events
decoupling of species relationships
spread of invasives/disease
change in sex ratios of environmental temp. determination
Are extinctions possible from climate change?
yes some species will run out of suitable habitat that they can't shift to
Is there evidence of organisms shifting timed events with the climate change
Some species can but there is evidence that some species cant (short distance vs long distance migrants) and this can cause competition and disadvantages
How does climate change effect species invasions?
with delayed winters, species can expand faster and longer causing adverse reactions in an ecosystem
What is the difference between mitigation and adaption?
Mitigation reduces the release of greenhouse gases by reducing fossil fuel burning , change to non polluting energy resources, and global reforestation

the other is adaptation to the changing climate which is unpredictable and could have terrible consequences
How can we help species with climate change?
assess vulnerability of species and habitats

design reserves for species that need to shift

establish habitat corridors for dispersal

assisted dispersal of some species northward

dynamic conservation plans

reduce effect of stressors

minimize catastrophic fires

maintain genetically diverse populations
What are utilitarian values?
values that make a species worthwhile as a means to help human beings achieve their ends
What are intrinsic values?
makes a species worthwhile in its own right as an end itself
What are the 4 utilitarian values?
Describe species that are goods
only a small portion
value is quantified and monetized
Describe species that provide services
includes more species
services include decomposition, nitrogen fixation, pollination
Describe species that provide information
biotechnology depends on genetic information stored in wild species
Describe species that provide inspiration
attraction to wild species- biophilia hypothesis
usually charismatic mega vertebrates
What are commodity values
people are willing to pay when there is a market for a species
what are option values?
what people are willing to pay to guarantee option of finding future use for a species
what are contingent values?
what people would be willing to pay for the opportunity to use a species
what are existence values?
what people are willing to pay to keep a species from going extinct even if they never see or use the it
what are bequest values?
what people are willing to pay to assure future generations have opportunity to use a species
What is the advantage and disadvantages of using utilitarian values for conservation?
able to win some arguments but can cause a cost benefit dilemma
What is the advantage of using intrinsic values as an argument?
shifts the burden to developers
What is the 'safe minimum standard'?
assumes that biological diversity is of incalcuable value and should always be conserved
What is anthropocentric ethic?
species are resources that exist to benefit humans
What is stewardship ethic?
human beings are responsible caretakers of wild species
What is biocentric ethic?
individual human beings should respect rights of individuals of other species
What is eccocentric ethic?
the human species is coequal with other species which should not be threatened by human actions