Unit 1 Test - Ecosystems and Biodiversity Flashcards
What are the ways of knowing?
The different paths we take to understanding ourselves and our environment
How is the scientific way of knowing characterized?
Observations of the natural/physical world to understand how the natural/physical world works (at least in part)
What are ways of knowing other than science?
Faith, intuition, myth, and revelation
What is the point of other ways of knowing?
ALL ways of knowing add value to the human experience, but in unique ways
Benefit of scientific way of knowing?
Allows us to make confident predictions, which can be extremely valuable
Benefit of faith/intuition way of knowing?
Allows us to ponder the supernatural, which is also meaningful
What are the limits of science? (4 of them)
Science doesn’t make moral or aesthetic judgments, tell us how to use scientific knowledge or draw conclusions about supernatural phenomena or explanations
The Nature of Science definition
How we describe all the characteristics that distinguish science as a way of knowing from all other ways of knowing
Why is the Nature of Science important?
It enables you to critically consumer information and then make confident, informed, evidence-based questions about personal and societal issues
Is scientific knowledge open to revision in light of new evidence?
Yes, it is simultaneously reliable and subject to change. This is one of the characteristics of science as a way of knowing
Do scientific investigations use a variety of methods?
Yes, there is no single step-by-step method that captures the complexity of doing science, thought there are many shared values and perspectives that characterize the scientific approach to understanding nature. This is one of the characteristics of science as a way of knowing
Is scientific knowledge based on empirical evidence?
Yes, all scientific knowledge is a combination of observations and inferences based on empirical evidence. This is one of the characteristics of science as a way of knowing
Empirical definition
Based on observation or experience, as opposed to theory or pure logic (trying it out rather than just thinking it through)
Is science a human endeavor?
Yes, which has several implications for science involving creativity, subjectivity, geolocation, and science’s effects. This is one of the characteristics of science as a way of knowing
How is creativity part of science?
Since science is a human endeavor, creativity is a vital, yet personal, component in the production of scientific knowledge
How is subjectivity part of science?
Since science is a human endeavor, subjectivity and bias are unavoidable because science involves individual human thinking and perceptions (which is why we have peer review)
How is geolocation part of science?
Scientific contributions can be and have been made by people in any part of the world
Explain science’s effects?
Since science is a human endeavor, science does not occur in a vacuum, so it affects societies and cultures, and is in turn affected by the societies and cultures within which it is conducted
Does science address questions about the natural/physical world?
Yes, it by definition is limited to naturalistic methods and explanations. This is one of the characteristics of science as a way of knowing
Do scientific laws, models, mechanisms, and theories describe and explain natural phenomena?
Yes, a primary goal of science is to form laws and theories, which are terms with VERY specific meanings. This is one of the characteristics of science as a way of knowing
What are scientific LAWS?
They describe universal relationships related to how some aspect of the natural world behaves under certain conditions, so they can predict the results of intital conditions
Scientific law examples?
Newton’s Laws of motion predict how far a baseball travels when hit by a bat swung with a certain force, and Boyle’s Law of gas predicts the pressure in your car tires on a hot vs cold day
What are scientific THEORIES?
They are inferred explanations of some aspect of the natural world, so they try to provide the most logical explanation for why things happen the way they do
Scientific theories examples?
Newton’s Theory of Gravity explains why a baseball makes an arc in the air after it’s hit, and Darwin’s Theory of Evolution by natural selection explains why populations of organisms change over time
Scientific LAWS vs THEORIES?
Scientific laws predict what happens, while scientific theories propose why
What must all well-established laws and theories do?
Be consistent and compatible with best available evidence, be successfully tested in a wide range of situations, and be applicable to and consistent with ongoing scientific research and discoveries
Ecosystem definition
A unit of biology comprised of living elements that interact with each other AND their non-living environments. Can be natural or human-made, and different sizes
Ecosystem function definition
The ecological processes that control fluxes and flows of materials (nutrients, organic matter), energy (sunlight, stored energy), and info (DNA) through an environment
What are some ecosystem functions in a terrestrial ecosystem?
Water and air penetrate soil, plant/animal matter breaks down into soil, decomposers break down organic matter, and soil stores nutrients which plants absorb
What are some ecosystem functions in an aquatic ecosystem?
Photosynthesis, bioturbation, benthivory, nutrient excretion, sinking particles, wave action, depth/stratification, emergence, and nutrient cycling
What are some ecological processes that control the fluxes and flows of materials?
Eating, pooping, bioturbation (animals mixing stuff up), animal migrations, sinking, wind and water currents, death, and decomposition
What are some ecological processes that control the fluxes and flows of energy?
Photosynthesis, chemosynthesis, food webs and trophic interactions
What are some ecological processes that control the fluxes and flows of information?
Sexual and asexual reproduction, animal migrations, and seed dispersal
Ecosystem services definition
The benefits (supporting, provisioning, regulating, and non-material) that people obtain from ecosystems which hold special value for humans and make human life possible
What are supporting ecosystem services?
Necessary for production of all other ecosystem services
Supporting ecosystem services examples?
Habitat, photosynthesis, soil formation, and biodiversity
What are provisioning ecosystem services?
The material benefits people get from ecosystems
Provisioning ecosystem services examples?
Building materials, fibers, medicine, and paper
What are regulating ecosystem services?
The benefits obtained from ecosystem processes
Regulating ecosystem services examples?
Storm protection, pollination, clean water, and climate regulation
What are non-material ecosystem services?
The benefits obtained from the educational, cultural, and aesthetic values of the ecosystem
Non-material ecosystem services examples?
Enabling scientific research, inspiring research and development, nature holding great importance to many cultures and spiritualities
How have indigenous people contributed to medicinal knowledge?
Indigenous peoples globally have cultivated vast knowledge on the medicinal properties of many plants over many generations
Bioprospecting definition
Exploring biodiversity resources for their potential to provide ecosystem services to humans, carries out by researchers, companies, and institutions
Biopiracy definition
The unauthorized appropriation of biological knowledge by individuals or institutions seeking control through patents or intellectual property rights
Case of the Pacific Yew summary?
Pacific Yew tree found to have Taxol (highly effective cancer drug) is on many Native American tribes of the PNW’s lands. Bristol-Myers was given exclusive rights to Taxol, aside from Native lands, which continued until public urged fed gov to better manage the Pacific Yew population, eventually switching to synthetic Taxol
Ethnobotany definition
The study of how people of a particular culture and region make use of indigenous (native) plants
Biodiversity definition
The variety of life that exists in the world, or in a particular habitat or organism
How can we define variety of life?
There are several ways, or “levels”
What is the first level of biodiversity?
Genetic variety/diversity (within a species)
What is genetic variety/ diversity?
Refers to the diversity that exists among organisms of the same species (in their genetic material, DNA)
What is genetic diversity’s relationship with species survival?
The greater the genetic diversity, the greater the chance of survival (for ALL species)
What is the second level of biodiversity?
Species variety/diversity (within an ecosystem)
What is species variety/ diversity?
Refers to the number (and relative abundance) of different species all inhabiting the same ecosystem
Which is the most common level of biodiversity?
The second level, of species diversity
How do we define a species?
The sum of all the populations of similar organisms that are reproductively compatible, and produce living offspring that can also reproduce
What traits do two different species have? (usually)
They are reproductively isolated from each other, look different from each other, and have unique evolutionary histories
What is the most common way to measure biodiversity?
Measuring species diversity is the most common measure, largely because it is so straightforward
How can we measure species diversity?
By counting all the different species in an ecosystem or defined area
How many species in our “defined area” of Earth?
We don’t exactly know, but we estimate from 7-9 million
How can we measure functional diversity?
Counting all of the different functions provided by species in an ecosystem (multiple different species could be serving the same function)
Keystone species definition
A keystone species has a disproportionately high impact on its ecosystem compared to its relatively low abundance in that ecosystem. Often have most impact on ecosystem via trophic interactions with a single or few prey species and often are high tropic level predators
How are the relationships between biodiversity and ecosystem function represented?
Four general hypotheses (models), which we know now are all oversimplified and wrong, but their underlying principles are true and they can be useful
What is the LINEAR relationship model between biodiversity and ecosystem function?
The more biodiversity (functional diversity aka more species each doing something different for the ecosystem), the higher level of overall ecosystem function
How do the species’ functions vary in the LINEAR relationship model between biodiversity and ecosystem function?
Each species in this ecosystem provides an equally unique and important function for the ecosystem
How would the loss of a species affect the ecosystem of a LINEAR relationship model between biodiversity and ecosystem function?
The loss of any one species would have the same effect on ecosystem function as any other species
Key idea of LINEAR relationship model between biodiversity and ecosystem function?
High functional diversity among species = HIGH overall ecosystem function
Success of ecosystem of LINEAR relationship between biodiversity and ecosystem function?
If it’s the only existing relationship in an ecosystem, it can be fragile, as certain functions depend on a single species if there is no functional redundancy
What is the REDUNDANT relationship model between biodiversity and ecosystem function?
Each species that is added to an ecosystem increases the function of that ecosystem to a point, but then eventually adding new species doesn’t really affect the ecosystem function
How do the species’ functions vary in the REDUNDANT relationship model between biodiversity and ecosystem function?
Some species in this ecosystem provide unique functions for this ecosystem, but many do not (they provide a function already provided by another species present in the ecosystem
Key idea of REDUNDANT relationship model between biodiversity and ecosystem function?
Biodiversity + Functional redundancy = STABILITY
Success of ecosystem of REDUNDANT relationship between biodiversity and ecosystem function?
Can be more stable, as the redundancy provides buffering against species loss, as long as there is enough foundational biodiversity in the system (as long as a sufficiently high ecosystem function exists in the first place)
What is the KEYSTONE relationship model between biodiversity and ecosystem function?
When the keystone species is lost, that causes a drastic, sudden drop in ecosystem function, but when other non-keystone species are lost, there is relatively less effect on ecosystem function
How do the species’ functions vary in the REDUNDANT relationship model between biodiversity and ecosystem function?
There is a single, extremely important species in this ecosystem which contributes a disproportionately high amount of functionality to the ecosystem
Success of ecosystem of REDUNDANT relationship between biodiversity and ecosystem function?
Very unstable since all depends on the survival of the keystone species
What does the relationship between ecosystem functions and ecosystem services look like?
Generally a positive, linear relationship (with function on X axis, service on Y axis)
Why is it important to know which conditions produce the highest ecosystem functions?
So that we can protect those ecosystem functions, and obtain the highest level of ecosystem services
Biodiversity, ecosystem functions, and ecosystem services connection examples?
-Forest biodiversity increases -> pollination increases -> crop production increases
-Forest biodiversity increases -> tree/shrub growth patterns increase -> storm protection increases
-Forest biodiversity increases -> resistance to pests/invasives increases -> pest/invasives regulation increases
-Forest biodiversity increases -> biomass production increases -> building materials increase
What is the relationship between ecosystem services and biodiversity itself?
Positive, linear relationship
Ways to help protect biodiversity (and in turn ecosystem functions and services)?
Create alternative lawns, diverse turfgrass ecosystems, pollinator habitats and “No Mow” zones
How can we define biological evolution?
Changes in a population of organisms over time, more specifically changes in the frequency of inherited traits over successive generations in populations of organisms
Population definition
A group of individuals that are all the same species
What is micro-evolution?
Going from one generation to the next, and considering the changes in the population with each new generation (at the genetic level). Small-scale and deals with shorter periods of time
What is macro-evolution?
What we see when we look at the over-arching history of life, including divergence of populations and the evolution of different species from a common ancestor over many generations. Large-scale
Where did the ideas about life’s history of change come from?
Partially from Darwin’s Origin of Species, but other scientists reached similar conclusions
Who is Alfred Russel Wallace?
Scientist around Darwin’s time who wrote a paper presenting natural selection and reached the same conclusions as Darwin independently
Why did Darwin’s “On the Origin of Species” get famous?
He published for a general audience, not scientists, and got most/all of the theory’s credit
What mechanisms drive biological evolution?
-Natural selection (key and powerful; Darwin and Wallace’s main idea)
-Migration (gene flow)
-Founder effect
-Genetic drift
-Bottleneck
-Sexual selection
Natural selection definition
The process whereby organisms that happen to be better adapted to their environment tend to survive and produce more offspring (Main driver of biological evolution and depends on genetic diversity within a population of organisms)
Steps of natural selection
- Individuals of a population vary in their heritable traits
- Struggle to exist under a selective pressure from the environment
- Individuals with more favorable trait variations in the environment will survive more than those without them
- Over multiple generations, the population as a whole becomes adapted to the environment as each new generation has a higher frequency of favorable traits
Selective pressure definition
Any external agent that leads to differential survival among individuals in a population due to different traits they happen to have
Selective pressure examples
Disease/pathogen, new predator, change in predation vulnerability, climatic event, change in food type/availability, or change in habitat type/availability
What does genetic diversity do?
Allow populations to respond to selective pressures or environmental changes without going extinct
How did we get genetic pressure to begin with?
Changes in specific nucleotide sequence within DNA (aka mutations)
Mutation definition
Permanent changes in genetic information that can be passed from parent to offspring IF they occur in gametes (egg or sperm) and therefore can be a factor in the outcome of natural selection
What can cause mutations?
Exposure to radiation or chemicals, mistakes when the cell copies DNA, viruses, etc.
Why do mutations occur?
At random with respect to the selective pressure, and not in response to necessity for survival or reproduction or induced by selective pressure
How can biodiversity be described as a driver of evolution?
Biodiversity at the genetic level drives the process of natural selection because it allows for trait variability within a population
How do we observe macroevolution?
Since its timescale surpasses the amount of time humans have been on earth, we rely on observed microevolutionary processes combined with geology, fossil evidence, and characteristics of living organisms
Speciation definition
Formation of new species
How does speciation occur?
Over time, two different populations of the same species can separate and eventually form two different species, and when this process repeats again and again over billions of years, we achieve the biodiversity that exists today
What’s the formula for macroevolution?
Microevolution + 3.8 billion years = macroevolution
How often do speciation events happen?
Typically in bursts, as species tend to exist relatively unchanged for a long time then a rapid environmental change drives rapid evolutionary change that results in new species
What happens when the rate of species lost exceeds the rate of new species formed?
The loss of biodiversity
How can we stop the loss of biodiversity due to speciation being outpaced?
We don’t have millions of years to wait for the lost biodiversity to be replaced, so the most important thing we can do now is conserve what we do have
Reproductive isolation definition
When two populations cannot mate and/or produce viable offspring, regardless of geographic isolation
What are the two main reproductive isolation mechanisms?
Pre-zygotic and post-zygotic mechanisms
What are pre-zygotic mechanisms?
Reproduction is inhibited BEFORE the zygote (fertilized egg) is created, preventing the union of sperm and egg
What are the types of pre-zygotic mechanisms?
Temporal, ecological/habitat, behavioral, and mechanical
What is the temporal pre-zygotic mechanism?
Occurs when two species mate at different times of the year
Temporal pre-zygotic mechanism example?
Frogs live in the same pond breed during different seasons (summer vs spring)
What is the ecological/habitat pre-zygotic mechanism?
Occurs when two species occupy different habitats
Ecological/habitat pre-zygotic mechanism example?
Lions and tigers can potentially interbreed but usually occupy different habitats
What is the behavioral pre-zygotic mechanism?
Occurs when two species have different courtship behaviors
Behavioral pre-zygotic mechanism example?
Certain groups of birds will only respond to species-specific mating calls
What is the mechanical pre-zygotic mechanism?
Occurs when physical differences prevent copulation/pollination
Mechanical pre-zygotic mechanism example?
The genitalia of a male bushbaby will only fit into the genitalia of a same-species female
What are post-zygotic mechanisms?
Inhibit reproduction AFTER the zygote (fertilized egg) is created. A hybrid offspring is formed, but it cannot reproduce sufficiently to support future generations
What are the types of post-zygotic mechanisms?
Hybrid/offspring inviability, hybrid infertility, and hybrid/generational breakdown
What is the hybrid/offspring inviability post-zygotic mechanism?
Hybrids are produced but fail to develop to reproductive maturity
Hybrid/offspring inviability post-zygotic mechanism example?
Certain types of frogs from hybrid tadpoles that die before they can become a frog
What is the hybrid infertility post-zygotic mechanism?
Hybrids fail to produce functional gametes
Hybrid infertility post-zygotic mechanism example?
Mules are sterile hybrids resulting from mating between a horse and a donkey
What is the hybrid/generational breakdown post-zygotic mechanism?
F1 hybrids are fertile, but F2 generation fails to develop properly
Hybrid/generational breakdown post-zygotic mechanism example?
The offspring of hybrid copepods have less potential for survival or reproduction
Where are the genetic differences for pre-zygotic and post-zygotic genetic differences coming from?
Mutations and sexual reproduction
What is the history of biodiversity on earth?
Shown in “Geologic Time”
What is the biodiversity crisis?
The loss of our natural biodiversity at an alarming and dangerous rate
What is causing the biodiversity crisis?
Habitat loss, invasive species, over-exploitation, pollution, and climate change
Habitat loss definition
Usually linked to changes in the way humans use land (land-use changes)
Land use change causes
Destruction of natural (undeveloped) land for inhabiting or making a living, as a by-product of other activities, as fragmentation by roads, and as fragmentation by other human constructions
Land use changes for resources in or on that land examples?
Mining for resources, cutting down trees for timber, and bottom trawling for fish
Land use changes for inhabiting or making a living examples?
Housing development/ urbanization, clearing land for growing crops, and clearing land to graze as pasture
Land use changes as a by-product for other activities examples?
Agricultural runoff (large scale), oil spills, mining runoff, and agricultural runoff (local scale)
Land use changes due to fragmentation by human construction examples?
Roads, dams, agriculture, and urbanization
Habitat fragmentation definition
Breaking up of habitat into smaller, unattached pieces
Why is habitat fragmentation an issue?
Breaks up and isolates populations, and creates more edges and therefore makes habitats more vulnerable to “edge effects”
Edges (of habitats) definition
The part of the ecosystem on the perimeters
Edge effects definition
The influences of adjacent habitat on edge habitat, resulting in environmental differences between the edge and interior. Edges are more exposed to weather and other environmental influences, such as noise, direct sunlight, temperature, and humidity, which can affect the health and survival of organisms that live in fragmented habitats
What does the habitat fragmentation breaking up and isolating of organism populations do?
The number of organisms in each new, fragmented population is smaller, which also reduces the gene pool, leading to a lower genetic diversity in the population and vulnerability to negative effects of inbreeding and not being able to survive selective pressures
How can we help avoid and reverse habitat loss?
Increase available habitat and protect what remains by creating designated spaces like wilderness areas, wildlife preserves, and marine protected areas
What are the benefits of restoring fragmented or isolated populations?
Connecting fragmented populations allows gene flow, increasing genetic diversity, increasing biodiversity, increasing ecosystem function, and increasing ecosystem services
What are ways to help restore fragmented or isolated populations?
Reconnect fragmented habitat (e.g. wildlife corridors, crossing structures) and introduce new genetic diversity into an isolated population
Wildlife structures definition
Create new habitat that connect areas of existing habitat so that fragmented populations can be restored
Wildlife structures examples?
Florida Wildlife Corridor, Yellowstone to Yukon corridor, and creating habitat corridors for jeweled geckos in New Zealand by planting Coprosma shrubs
Crossing structures definition
Human-made structures over/under roads that connect fragmented habitat
Crossing structures example?
Animal underpasses and overpasses in Banff National Park
What are the benefits of introducing new genetic diversity into an isolated population?
Prevent inbreeding and improve ability to withstand selective pressures
Introducing new genetic diversity into an isolated population example?
Florida Panthers
Florida Panther summary?
Were inbred and isolated after years of habitat loss and over-exploitation, expected soon extinction, biologists moved Texas cougars to Florida to mate, producing non-inbred kittens, and now population is healthy and expanding
What happened to the FL Panther population after the TX population was introduced?
FL population survived and increased
Why did cross-breeding among different populations of panthers help the FL population survive and increase in number?
Increased genetic diversity
How and why does genetic variation affect a population’s ability to survive in the face of disease and parasites?
Increased chances that a certain genetic combination will allow an individual to better fend off diseases/parasites
What was the primary mechanism/process that increased genetic diversity in the FL population during this short amount of time?
Sexual reproduction
Why were there such significant genetic differences between the two populations (FL and TX)?
Evolution. The two populations were geographically isolated, did not interbreed, and that allowed their populations to genetically diverge to an extent due to the different environments, random events, and selective pressures they experienced, even though they were the same species
Invasive species definition (according to federal law)
A non-native species whose introduction does or is likely to cause economic harm or environmental harm or harm to human health
Non-native species definition
A species not naturally found in an ecosystem (also sometimes called “exotic species” or “introduced species”)
Non-native US species examples? (non-harmful)
DC’s cherry trees (native to Japan), ring-necked pheasant (native to temperate regions of Asia), and tulips (native to Islamabad and Pakistan)
Non-native US species examples? (harmful/invasive)
Zebra mussels, buckthorn, kudzu, and Asian carp
Native species definition
A species naturally found (has naturally evolved) in an ecosystem
Native species US examples?
Bald eagle, wild turkey, American bison, and red maple
Endemic species definition
A native species that is naturally found nowhere else on earth (has uniquely evolved in a very specific location/environment)
Endemic species US/GA example?
Pigeon mountain salamander
How do invasive species threaten biodiversity?
Invasive species often outcompete native species for food, habitat, and other resources, causing native populations to suffer, be displaced, or sometimes go extinct. Any time a population or species is displaced from an ecosystem or goes extinct altogether, biodiversity decreases
What is the cost of invasive species in the US?
$137 billion annually
How do invasive species invasions start?
Transport and introduction, whether intentional or unintentional
Transport definition (in invasive species invasions)
Movement to a non-native habitat
Introduction definition (in invasive species invasions)
Alive in new, non-native habitat
What makes an invasive species invasion successful?
High reproductive capacity, habitat generalism, dietary generalism, and few or zero predators in new habitat
Habitat generalism definition
Can survive in wide range of habitats and conditions
Dietary generalism definition
Can eat a wide range of food
Burmese Pythons case summary
Suspected release from FL pet store in hurricane, population established in Everglades, have negatively impacted native ecology and efforts to control cost around $1 million each year
What action is Florida taking against the Burmese Pythons?
Florida Python Challenge rewards hunters who capture pythons, and removed over 200 in 2011, but hasn’t much reduced the impact of the pythons
What are the solutions for invasive species?
Prevent invasions in the first place, kill or move all individuals of an invasive species, or manage invasive populations
How does the kill or moving all invasive species individuals solution work?
Rarely possible, but was successfully done with goats on the Galapagos by introducing sterile, female goats to find the male goats and capture them
How does the manage invasive populations solution work?
Stop it from spreading further, use another species (predator/grazer) to keep it under control, and kill enough individuals each year to limit population growth
Extinction definition (GLOBAL extinction)
Refers to the loss of a species from the entire planet
Extinction definition (MASS extinction)
Describes the losses of entire phyla, classes, or orders (i.e. many related species) from the planet
Extinction definition (LOCALIZED extinction)
Refers to the loss of species from a defined geographic area of ecosystem
Known extinctions during modern times examples?
Dodo bird, thylacine, Hawaii chaff flower, and St. Helena olive tree
Natural global extinction rate definition
Natural extinction occurs due to a species’ inability to adapt to natural changes in the environment
What is the natural/background global extinction rate?
1-16 species per year
What is the current estimated global extinction rate?
10-100 species per day
What cause do all 5 past mass extinction events have in common?
Climate change
Are we experiencing a 6th mass extinction event?
The rapid loss of biodiversity we are experiencing now is what students think might be a Sixth Mass Extinction event
What is causing the current potential 6th Mass Extinction event?
Human activities driving habitat loss, invasive species, pollution, over-exploitation, and climate change
Anthropocene definition
A proposed new geologic epoch that scientists say is due to the drastic impact our human activities have on the Earth
