ASU BIO320 online Exam 1 prep (cogbooks mod 1-4)

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Distinguish between a fundamental niche and a realized niche.

A realized niche is the range of biotic and abiotic conditions under which a species exists. The realized niche determines the geographic range of a species or of various populations that compose a species. Fundamental niche of a species is the range of abiotic conditions under which species can persist. This includes the range of temperature, humidity, and salinity conditions that allow a population to survive, grow, and reproduce.

Keystone species (organism)

A species on which other species in an ecosystem largely depend, such that if it were removed the ecosystem would change drastically. **example - Coral**

Ecosystems

A specific biological community and its physical environment interacting in an exchange of matter and energy.

Living Factors

Abiotic components or abiotic factors are non-living chemical and physical parts of the environment that affect living organisms and the functioning of ecosystems. Abiotic factors and phenomena associated with them underpin all biology.

Relate the abiotic conditions of a region to the species richness of that region.

Abiotic conditions, independent from living things, relates to the species richness in that, temperature, sunlight, oxygen, location, and closeness to water can affect how many species will live in a certain area.

Achieving an equilibrium number of species on an island.

Achieving an equilibrium number of species on an island. As the number of species living on an island increases, the rate of colonization by new species from the regional pool declines. At the same time, the rate of extinctions of species living on the island increases. The equilibrium number of species, Ŝ, occurs where the two curves cross and the opposing processes are balanced.

Contrast alpha diversity, beta diversity, and gamma diversity. Explain how each relates to the other.

Alpha diversity is just the diversity of each site (local species pool). Beta diversity represents the differences in species composition among sites. Gamma diversity is the diversity of the entire landscape.

Disease

An abnormal condition of an organism which interrupts the normal bodily functions that often leads to feeling of pain and weakness, and usually associated with symptoms and signs.

Example of Species sorting

An example of species sorting can be seen in an experiment in which researchers set up artificial wetlands and manipulated a variety of conditions, including the fertility of the soil and the amount of flooding the soil experienced. The researchers then sowed the seeds of 20 wetland plant species into each wetland to see which plants would germinate and persist over the next 5 years. Of the original 20 species, one species failed to germinate in any of the wetlands and five others were unable to persist. Of the remaining 14 species, each wetland contained only three to five species by the end of the experiment. Moreover, there were particular combinations of plant species that survived under each flooding and fertility condition. These results confirmed that differences in local conditions cause the sorting of species from the regional species pool.

Population Growth

An increase in population over a period of time.

Predation

An interaction in which one organism captures and feeds on another organism

The richness and abundance of insect-eating birds were highest in...

Areas containing a variety of habitat types, including shallow streams, meadows, and broadleaf forests. This mixture of meadow, forest, and stream habitats allows a greater variety of insect-eating shore birds and forest birds to exist and feed on the insects that emerge from the stream.

rate of extinction on an island factors:

As the island begins to be colonized, it holds a few species that could potentially go extinct. As more species live on the island, more species are subject to possible extinction, and so the extinction rate increases. The extinction rate should also be affected by harmful species interactions on the island. For example, competition, predation, and parasitism are all more likely to increase as the total number of species increases. The blue line in the first Figure shows that the extinction rate ranges from zero when no species are present on the island to a maximum rate of extinction when the island contains every species that it can possibly support.

The final biogeographic region is the _________ region, which includes Australia, New Zealand, and New Guinea.

Australasian region

A second way to estimate the number of species in an area is:

Based on the number of rare species that are detected. When we sample many individuals in a community, we typically end up with a high number of individuals for each of the common species but we may detect only one or two individuals of rare species.

Imagine that you visit a place for the first time. What metric(s) would you use to decide whether the place contains a rich biodiversity?

Biodiverse places have the following: * many different looking organisms. * many species (even if they look similar). * many alleles within populations of species. * heterogeneous distributions of life on a small scale (patchy texture).

In the relatively shallow North Sea, situated between the United Kingdom and Norway, temperatures in the bottom waters have increased more than 2°C since the 1970s

Changes in the distribution of fish in the north Sea. (a) From 1977 to 2003, the temperature of the water at the bottom of the North Sea increased by 2°C. (b) Surveys of fish trawls from 1985 to 2006 found that the total number of fish species collected per year in the North Sea increased from 60 to approximately 90. (c) The total number of fish species collected per year was positively correlated with the average sea temperatures during the previous 5 years. (Source: Data from J. G. Hiddink and R. ter Hofstede, Climate induced increases in species richness of marine fishes, Global Change Biology 14 (2008): 453-460.)

How do interactions between species promote or limit the number of species living in a region?

Competition usually limits biodiversity. In most cases, competition between species will prevent some species from persisting. In rare cases, however, competition promotes speciation through disruptive selection within populations. Mutualism benefits all species involved, and therefore promotes the persistence of those species. However, mutualism among one group of species can help this group out-compete other species. Predation can help maintain diversity when a predator limits the density of a dominant competitor. You may recall learning about such keystone species in an introductory biology class.

the Florida Wildlife Corridor is an excellent case study of the challenges presented by the design of nature reserves

Conservationists hope to link public and private land through the state of Florida in a way that promotes the movement of wild organisms between habitats and facilitates their long-term persistence.

What are the difference and relationships between ecology and evolution?

Ecology = interactions between the organisms and the environment .Evolution= change-> new environment-> new selective pressure

Explain how the fragmentation of habitat can enhance or inhibit biodiversity?

Fragmentation is the process in which a large area of habitat is transformed into small portions isolated from each other. This can inhibit biodiversity.

Who developed a way to visualize this pattern of variation in abundance of different species?

Frank Preston

Use the concept of a fundamental niche to explain why larger areas and more heterogeneous areas hold more species.

Fundamental niche is the full range of environmental conditions that a viable population of species can occupy and use, without any other limiting factors. So larger areas would hold more species due to no limit in abiotic factors and a equilibrium in survival of the fittest.

Greenhouse gases

Gases such as carbon dioxide, methane, nitrous oxide, water vapor, and ozone in the atmosphere which are involved in the greenhouse effect.

One way to estimate the number of species in a sample is to:

Graph the number of species that we observe as we increase our sample size. One would expect that the more we sample, the closer we will get to knowing the actual number of species in an area. Eventually, the curve will reach a plateau so that any additional sampling will not discover additional species.

At any given latitude, we find more species in areas where there is...

Greater ecological heterogeneity, such as heterogeneity in the soils and plant life.

regional diversity or gamma diversity

If we consider the number of species in all the habitats that comprise a large geographic area, we would be looking at regional diversity or gamma diversity.

To determine if environmental conditions cause these different species distributions, researchers planted the two species at locations within and outside of the elevations where they grow in nature. The results of this experiment are shown in Figure.

If we examine plant survival, we see that Lewis' monkeyflower survives well at high elevations but survives poorly at low elevations. The opposite is true for the scarlet monkeyflower. If we examine plant growth, a similar pattern emerges. Lewis' monkeyflower grows better as elevation increases, although growth declines under the extreme conditions of the highest elevation. The scarlet monkeyflower grows the best at low elevations and its growth declines with each increase in elevation. For each species, the survival and growth of the transplanted populations were the highest when grown within its normal elevation range. When grown outside this range, both species experienced lower survival and slower growth.

The effect of habitat fragmentation on edge habitat.

If we have two habitats of the same total area, the habitat that is fragmented has much more edge. The single large habitat would have 400 m of edge, whereas the 16 smaller habitats would have 1,600 m of edge. In regard to fragment shape, round habitats have the lowest ratio of edge to area, while long, skinny ovals or rectangles have much higher edge-to-area ratios.

Nonliving Factors

In biology and ecology, abiotic components or abiotic factors are non-living chemical and physical parts of the environment that affect living organisms and the functioning of ecosystems. Abiotic factors and phenomena associated with them underpin all biology

Using the data for Community A, we can estimate the actual number of species.

In this community, we have observed 12 species. Two individuals were observed for each of two species, whereas one individual was observed˜for each of three species. Using our equation above, we get.... (see image) Comm A. -> S = 13

Species evenness

Is a comparison of the relative abundance of each species in a community. The greatest evenness occurs when all species in a community have equal abundances, and the lowest evenness occurs when one species is abundant and the remaining species are rare.

Imagine two forests: a large forest with few gaps in the canopy; a patchy forest interrupted by fields of grass. How would you expect biodiversity to differ between of these forests? Think about the differences in terms of species, genes, and ecological processes.

Large forests should contain larger populations of each species, reducing loss of alleles by genetic drift. Large forest would contain only species that rely on resources in forests, but patchy forest might contain a mixture of species. Large forest would represent fewer ecological processes, because of one biome rather than a mixture of biomes.

By 150 Mya, Pangaea had separated into a northern landmass, known as __________, and a southern landmass, known as __________

Laurasia Gondwana

The loss of a keystone species (coral):

Leaves its dependents at a loss too, threatening the entire fabric of the reef.

How do abiotic factors promote or limit the number of species living in a region?

Light, water, oxygen, and heat are three abiotic factors that influence the amount of life that an area can sustain. Plants and algae require light to make carbohydrates (glucose). The biomass in these photosynthetic organisms supports the survival and reproduction of animals. Fungi and bacteria rely on the biomass of plants and animals as well. Therefore, the abundance of light will limit how many and which species can survive in an area. Additionally, places with little water will prevent many organisms from surviving. Too little or too much heat will prevent organisms from surviving as well, because metabolic reactions require a specific range of temperatures.

Log-normal distributions of species abundance

Log-normal distributions are found by plotting the abundance of categories of each species on a log2 scale and then plotting the number of species that contain each abundance category.

Human Disturbances

Logging, clearing land, pollution, global warming, ozone depletion

Legacy effects

Long-lasting influences of historical processes on the current ecology of an area.

How might the function of proteins limit the survival or reproduction of an organism?

Many examples are possible, as long as you connect the function of proteins to the function of an organism. For instance, proteins that transport ions must create membrane potential for the nervous system to function. Enzymes involved in cellular respiration produce the ATP required for all cellular work. Proteins involved in muscle contraction are needed to escape predators and capture prey.

Many sources of abiotic stress disrupt an organism's homeostasis. In previous biology courses, you learned how temperature, pH, and osmotic pressure affect the functions of proteins in cells. Use your understanding of these processes to answer the following questions. How might the function of proteins limit the survival or reproduction of an organism?

Many examples are possible, as long as you connect the function of proteins to the function of an organism. For instance, proteins that transport ions must create membrane potential for the nervous system to function. Enzymes involved in cellular respiration produce the ATP required for all cellular work. Proteins involved in muscle contraction are needed to escape predators and capture prey.

Use the theory of island biogeography to explain why larger islands usually have more species.

More space, equals more species.

Corridors facilitate...

Movement, which can save declining populations of many species from local extinction. They also increase gene flow and genetic diversity within populations, which counteract the negative effects of genetic bottlenecks and genetic drift. Corridors can simply be pieces of preserved habitat or they can be constructed, such as corridors built to let animals cross a highway. Corridors can rescue declining populations by adding new colonists that bring genetic variation.

Species that lack genetic diversity due to isolation or low populations numbers are:

Much more vulnerable to fluctuations caused by climate change, disease or habitat fragmentation.

Habitat islands can form when...

Natural processes such as fires and hurricanes cause habitats to become fragmented. Similarly, human activities have caused widespread fragmentation of large habitats throughout the world. For example, in the Central American nation of Costa Rica, the forests in 1940 covered much of the country and existed as a large, continuous habitat. As human populations and their associated activities increased, the forests were cleared on a continuing basis, as shown in figure. (see image)

The Northern Hemisphere is divided into the _________ region, which roughly corresponds to North America, and the ________ region, which corresponds to Eurasia.

Nearctic region Palearctic region

The Southern Hemisphere is divided into four biogeographic regions... The _________ region corresponds to Central and South America and the _________ region, also known as the _________ region, corresponds to most of Africa.

Neotropical region Afrotropical region (aka Ethiopian region)

Laurasia subsequently split into...

North America, Europe, and Asia

End of modules 1 - 4 in cogbooks

Now on to random bio vocab

The 'scientific method' includes:

Observations, experiments, and modeling; posing questions, and formulating testable hypothesis, and statistical analysis.

An island that is near a continent should experience higher rates...

Of colonization by new species than an island that is far from a continent.

About 250 Mya, all of Earth's landmasses were joined together as a single landmass, named...

Pangaea

Rank-abundance curves

Plot the relative abundance of each species in a community in rank order from the most abundant to the least abundant. Rank-abundance curves are particularly good for illustrating how communities differ in species richness and species evenness.

Choose one of these abiotic factors: temperature, pH, or osmotic pressure. How would the function of proteins suffer if an organism failed to regulate the abiotic factor?

Proteins rely of many weak bonds to create a 3-dimensional structure. This structure usually changes during function, such as when the active site of an enzymes binds substrates and catalyzes a reaction. A change in temperature can disrupt the 3-dimensional shape by removing too much kinetic energy (too cold) or adding too much kinetic energy (too hot). A change in pH could leave the cell with too many or too few hydrogen ions (protons) to maintain hydrogen bonds and ionic bonds within the protein. If the osmotic pressure rises too much, a cell becomes too viscous for proteins to function. If the osmotic pressure falls too much, a cell becomes too dilute for proteins to interact with substrates.

Many sources of abiotic stress disrupt an organism's homeostasis. In previous biology courses, you learned how temperature, pH, and osmotic pressure affect the functions of proteins in cells. Use your understanding of these processes to answer the following questions. Choose one of these abiotic factors: temperature, pH, or osmotic pressure. How would the function of proteins suffer if an organism failed to regulate the abiotic factor?

Proteins rely of many weak bonds to create a 3-dimensional structure. This structure usually changes during function, such as when the active site of an enzymes binds substrates and catalyzes a reaction. A change in temperature can disrupt the 3-dimensional shape by removing too much kinetic energy (too cold) or adding too much kinetic energy (too hot). A change in pH could leave the cell with too many or too few hydrogen ions (protons) to maintain hydrogen bonds and ionic bonds within the protein. If the osmotic pressure rises too much, a cell becomes too viscous for proteins to function. If the osmotic pressure falls too much, a cell becomes too dilute for proteins to interact with substrates.

Define evenness and use rank-abundance curves to compare the evenness of species between communities.

Rank abundant curve is a plot that is relative from most abundant to least abundant species. Evenness is the same amount of species in each community.

Describe how the rate of colonization and the rate of extinction combine to determine the number of species on a region such as an island.

Rate of colonization is the rate at which a species makes its home on an island, rate of extinction is how long the species can survive on the island. If there are not enough resources on the island, rate of colonization will slow and extinction rate will rise. And vice versa.

Biotic

Resulting from living things, especially in their ecological relations.

Who developed the equilibrium theory of island biogeography?

Robert MacArthur and E. O. Wilson

Estimate the number of species in a community from a sample of individuals.

S=Sobs + f1(f1-1)/2(f2-1)

Estimate the number of species that are present in Community B and Community C. Based on your results, how does the number of species represented by single individuals affect the estimated number of species in the community?

See image. Comm. B -> S = 22 Comm. C -> S = 8

The two most common and equally valid indices of species diversity are:

Simpson's index and Shannon's index. Both indices incorporate species richness, which we abbreviate as S, and evenness. However, they do so in different ways.

Ecosystem engineers

Some animals—for example, beavers and alligators—are ecosystem engineers and can alter the habitats in a landscape. Humans are the most extensive ecosystem engineers; they build homes, offices, and factories, construct dams and irrigation channels, channelize waterways for improved navigation, and clear forests for lumber, paper, and agriculture.

Choose two species: one that occurs throughout a large region and another that occurs only in a small region. Re-visit:What characteristics of these species or their environments might explain the difference in their distributions?

Some species are generalists, tolerating a wide range of abiotic conditions, whereas others are specialists Some species live commensally with humans, which have generated global distributions of urban or agricultural habitats Some species disperse wide and far, whereas others have limited means of dispersal Some species are isolated by geographical factors such as islands in oceans, lakes within continents, or ice at the poles

Gondwana split into....

South America, Africa, Antarctica, Australia, and India

How should the size of a meadow influence the number of species?

Species richness. Colonization of species goes down as the extinction of species goes up. Insects eat fluids of leaves, giving way to more parasitoid opportunities. More herbivorous insect species near a meadow also equals more parasitoids species by meadow. The greater the distance, the less species. pH, shade, nitrogen, phosphorus, temperature Abiotic conditions contribute to species richness more than area and connectivity do.

equilibrium theory of island biogeography

States that the number of species on an island reflects a balance between the colonization of new species and the extinction of existing species.

Conversely, in the habitat matrix between the fragments....

Such as cleared fields between forest fragments, the total area increases and the matrix becomes more continuous. Of particular interest is how isolated habitat patches with different sizes and shapes influence biodiversity, and how habitat corridors and the quality of the matrix between habitat fragments affect the rate of species turnover.

An increase in edge habitat changes both...

The abiotic conditions and the species composition of a habitat. In a fragmented forest, for instance, the edge of a newly created fragment experiences greater sunlight, warmer temperatures in the summer, and higher rates of evaporation. These changes can make the edge of the forest less suitable to many forest species and more suitable to others.

Given that fragmentation increases the amount of habitat edge, it also increases...

The abundance of those species that prefer edge habitat, and this can affect other species living in the fragment.

species sorting

The actual species that live in each local site depend on the species that exist in the regional pool and how well biotic and abiotic conditions at the local scale match the niche requirements of species in the regional pool. Therefore, species in the regional species pool are sorted among localities according to their adaptations and interactions, a process called species sorting

The highest level of ecological organization focuses on

The biosphere.

Carrying Capacity

The carrying capacity of a biological species in an environment is the maximum population size of the species that the environment can sustain indefinitely, given the food, habitat, water, and other necessities available in the environment.

An important consequence of continental drift was...

The changing opportunities for dispersal among continents. Once separated, continents could independently evolve species in different regions of Earth.

regional species pool

The collection of species that occurs within a region is called the regional species pool.

Human Impact

The effect of humans on an ecosystem

Landscape ecology

The field of landscape ecology considers the spatial arrangement of habitats at different scales and examines how they influence individuals, populations, communities, and ecosystems.

geographic range

The geographic range is a measure of the total area covered by a population.

Geographic range EXAMPLE

The geographic range is a measure of the total area covered by a population. For example, the American chestnut tree (Castanea dentata) was once a very common tree in the eastern forest of the United States because it grew and reproduced well under the abiotic and biotic conditions that existed in this region for thousands of years. Around 1900, however, a fungus (Cryphonectria parasitica) introduced from Asia caused a deadly disease known as chestnut blight. The fungus spread rapidly throughout the eastern forests and killed billions of trees. As a result of this biotic interaction between the chestnut trees and the fungus, few places remain where adult trees can persist. In short, the fungus has caused a major reduction in the realized niche of the American chestnut.

Global Temperature

The geography of life on earth is a consequence of the planet's movement through space. The sun radiates energy and heats the earth's surface than places where the sun's angle is further from the zenith...where the radiation is more spread out

Species area curve for amphibians and reptiles

The number of amphibian and reptile species living on islands in the West Indies increases with island size. (see image)

Patterns in North American Diversity

The number of mammals also increases as we move from east to west in North America. For instance, there are typically 50 to 75 species per sample block in the east, whereas there are 90 to 120 species per block in the west. Such a pattern is likely due to the greater amount of habitat heterogeneity in the extensive mountain ranges of western North America. This greater heterogeneity of environments in the west apparently provides suitable conditions for a greater number of species.

species-area curve

The observation that larger areas tend to contain more species has led to the concept of the species-area curve. The species-area curve is a graphical relationship in which increases in area (A) are associated with increases in the number of species (S). This curve can be described by the following equation: S = cA^z where c and z are constants fitted to the data. To make it easier to work with this equation in the form of a graph, we can take the logarithm of both sides: log S = log c + z log A This is the equation for a straight line with a y-intercept of log c and a slope of z. For example, Figure b plots the same amphibian and reptile data using axes on a log scale. A similar linear relationship can be seen in another collection of data by MacArthur and Wilson in which they examined the number of bird species living on the Sunda Islands in Malaysia, the Philippines, and New Guinea. As you can see in figure. (see image)

ecological niche modeling

The process of determining the suitable habitat conditions for a species is known as The process of determining the suitable habitat conditions for a species is known as ecological niche modeling. Because temperature and precipitation have a dominant influence on the distribution of biomes, modelers often begin by mapping the known locations of a species and then by quantifying the ecological conditions at the locations where the species has been recorded. The modeler can potentially include many additional variables such as different soil types and the presence of potential predators, competitors, and pathogens that might limit the population's distribution.

Relative abundance

The proportion of individuals in a community represented by each species. Some high/low, most intermediate.

realized niche

The range of abiotic and biotic conditions under which a species persists is its realized niche. The realized niche determines the geographic range of a species or of various populations that compose a species.

Define an ecological envelope and explain the application of this concept in ecological niche modeling.

The range of ecological conditions that are predicted to be suitable for a species is the ecological envelope of the species. The process of determining the suitable habitat conditions for a species is known as ecological niche modeling.

ecological envelope

The range of ecological conditions that are predicted to be suitable for a species is the ecological envelope of the species. The concept of the ecological envelope is similar to the realized niche, but the realized niche includes the conditions under which a species currently lives, whereas the ecological envelope is a prediction of where a species could potentially live.

What is ecology

The study of relationships between organisms and the environment.

Fragmentation of a large contiguous habitat creates several effects:

The total amount of habitat decreases, the number of habitat patches increases, the average patch size decreases, the amount of edge habitat increases, and patch isolation increases.

Ecosystems Diversity

The variety of habitats, communities, and ecological processes with and between ecosystem

Species richness increases with habitat area

They found that as wetland area increased, there was a corresponding increase in the number of species of plants, amphibians, reptiles, birds, and mammals. As you can see, the positive correlation between area and species richness is common in nature. (see image)

Oceanic islands provide a good test of how colonization and extinction affect the number of species...

They found that both island area and the distance from New Guinea affected the number of species living on the island. For islands of a given distance from the mainland, large islands contain more species than small islands. For islands of a given area, near islands contain more bird species than far islands.

Robert MacArthur and E. O. Wilson examined the patterns of species richness in taxonomic groups living on islands of different sizes. When they plotted the species richness of different islands against the size of the islands...

They found that larger islands had a greater species richness.

patterns of marine biodiversity

They found that the highest diversity occurred in the tropics including Central America and Southeast Asia, whereas the lowest diversity occurred near the poles where temperatures are colder. At a given latitude, they also found a higher diversity near the coasts and lower diversity in the open ocean.

Activity: Write a figure legend.

This is the proportion of plants surviving on the y-axis here that we're reared in the hot and cold conditions mimicking this would be at the bottom of the mountain right.

example of how small-scale variation in the environment can create geographic ranges that are composed of small patches of suitable habitat.

This small range is thought to be the result of climatic conditions and competitive interactions with ecologically similar plants. Within its geographic range, the plant is restricted to dry, rocky soils on outcroppings of limestone, known as limestone glades, which are similar to the glades frequented by the collared lizard discussed at the beginning of this chapter. Small variations in elevation and soil quality further confine these plants within each limestone glade to sites with suitable soil structure, moisture, and nutrients. Local aggregations occurring on each of these sites consist of individuals that are fairly evenly distributed in space. In other words, while Fremont's leather flower has a geographic range that includes three counties, its distribution is spotty in this region due to its narrow habitat requirements.

Environmental Factors

Those "nonbiological" factors that are involved in a person's surroundings such as the nature of the person's parents, the person's friends, and the person's behavioral choices

Activity: Design an experiment to see whether the niche limits each species' range.

Transfer plants from different environments, to different altitudes and see if they can survive. Using a high sample size. Using a control of mimicking the stress of transplanting the flowers.

Design and interpret an experiment that defines the geographic limits of a species.

Transfer plants from different environments, to different altitudes and see if they can survive. Using a high sample size. Using a control of mimicking the stress of transplanting the flowers.

Suppose a friend wants to take an exotic trip and asks you to recommend a place with tremendous biodiversity. What place would you recommend and why?

Tropical rainforest in equatorial regions of Central/South America, Australia, or Africa. *biome *species richness *productivity

True / False Ecological niche modeling can be a useful way to predict the expansion of pest species introduced to a continent where they have not previously lived.

True

True / False? Biodiversity in marine environments is greater in the tropics than it is at higher latitudes.

True

True or False? The number of species found at any location as one moves from the poles to the tropics is positively correlated to the amount of solar energy and precipitation at that location.

True

We can estimate the number of species actually living in an area:

We can estimate the number of species actually living in an area (S) by sampling the community to determine how many species are observed (Sobs), how many species are represented by two individuals (f2), and how many are represented by one individual (f1).

ecotones

When habitats are fragmented, they produce ecotones, which are regions with distinct environmental conditions and unique species compositions over a relatively short distance. Increases in fragmentation cause an increase in the amount of edge habitat compared to the amount of edge present in the original unfragmented habitat.

Global Warming

a gradual increase in the overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, chlorofluorocarbons, and other pollutants.

Population Density

a measure of the number of organisms that make up a population in a defined area.

Ecological Disturbances

a temporary change in environmental conditions that causes a pronounced change in an ecosystem

Shannon's index (H')

aka Shannon-wiener index. Another measurement of species diversity given by formula. (see image) ** We multiply each of the relative abundance values by the natural log of the relative abundance values, sum these products, and then take the negative sum. *** Can range from a minimum value of 0, which represents a community that contains only one species, to a maximum value that is the natural log of the number of species in the community. As we saw with Simpson's index, the maximum species diversity value occurs when all species in the community have the same relative abundances. one species) to m

The patterns of species richness across and within latitudes are potentially affected by...

all three processes of habitat heterogeneity, temperature and precipitation on land, and mean temperature in the oceans. In all three cases, the mechanisms involved suggest that the global distribution of species richness is the outcome of an equilibrium between the processes that create new species and the processes that cause the extinction of existing species.

Physical Disturbances

any relatively discrete event in time that disrupts ecosystem, community, or population structure and changes resources, substrate availability, or the physical environment

When we think about the geographic range of a species or population, we need to realize that individuals often do not occupy every location within the range. This is because....

climate, topography, soils, vegetation structure, and other factors influence the abundance of individuals.

Limited Resources

common limiting factor resources are environmental conditions that limit the growth, abundance, or distribution of an organism or a population of organisms in an ecosystem.

The continents have repeatedly come together and drifted apart in a process called...

continental drift.

Unintended downside of corridors...

corridors built to help conservation of a particular species can facilitate the movement of predators (including poachers), competitors, and pathogens that are harmful to conservation efforts. Therefore, resource managers must carefully consider the costs and benefits of developing corridors among habitat before spending time and money to implement this strategy.

Habitat Loss

destruction or disruption of Earth's natural habitats, most often due to human actions such as agriculture, forestry, mining, and urbanization

habitat heterogeneity also plays a role in...

determining species richness when two habitats have similar levels of productivity. For instance, habitats with less variation in vegetation growth form, such as grasslands, have fewer animal species than habitats with similar productivity but more variation in vegetation. This principle also applies to plants. Marshes are highly productive but have a relatively uniform landscape and thus contain relatively few species of plants. While desert vegetation is less productive than marsh vegetation, the greater heterogeneity of the desert landscape provides room for more species of plants

Biological disturbances

disturbance brought about by the behaviors of the organisms (digging, grazing, predation, competition)

Contrast three ways that biologists define biodiversity.

ecosystem, species, genetic

The correlations between PET and species richness for terrestrial vertebrates have given rise to the idea that this correlation may actually represent a causal relationship between the two variables. This hypothesized causal relationship is known as the...

energy-diversity hypothesis, which states that sites with higher amounts of energy are able to support more species. Higher amounts of energy would also support higher abundances of individuals from each species, which should reduce the rate of extinction. Moreover, higher energy input might accelerate the rate of evolutionary change and thereby increase the rate of speciation. While these ideas are attractive, none of these mechanisms has yet been verified.

Limiting Factors

environmental conditions that limit the growth, abundance, or distribution of an organism or a population of organisms in an ecosystem.

extinction rate

expressed as the number of species that will go extinct over a period of time, the extinction rate must be affected by how many species are present. In the simplest case, when there are no species, there can be no extinctions.

Ecologists in Vermont recently surveyed bird species along 27 streams that feed into Lake Champlain... They found fish-eating birds were more abundant in

fish-eating birds were more abundant in larger streams with little agriculture along the stream bank because such streams contain more fish

The _______________ of a species is the range of abiotic conditions under which species can persist. This includes the range of temperature, humidity, and salinity conditions that allow a population to survive, grow, and reproduce.

fundamental niche

Climatic Changes

global change causes ecological disturbances that increase the incidence and distribution of infectious diseases changes in weather/climate

Population Diversity

interactions between abiotic and biotic factors causing variation in population size

Ecological Succession

is the observed process of change in the species structure of an ecological community over time.

Biodiversity

is the term given to the variety of life on Earth. It is the variety within and between all species of plants, animals and micro-organisms and the ecosystems within which they live and interact.

the only significant predictor of marine biodiversity across latitudes was the...

mean temperature of the sea surface. Because a higher mean temperature is a measure of greater total energy, this pattern further supports the energy-diversity hypothesis.

Carbon Footprint

measure of the impact human activities have on the environment in terms of the amount of greenhouse gases produced, measured in units of carbon dioxide

Given that most species of fish have ________________________, we might predict that warming ocean waters could cause southern fish species, which live in warm waters, to move north.

optimal temperature ranges

stepping stones

organisms such as birds and flying insects can pass over stretches of inhospitable habitat matrix and therefore may not need a continuously connected corridor. Instead, these species can move between large patches of favorable habitat if they have access to small intervening patches where they can stop to rest or forage. These small intervening patches that dispersing organisms can use to move between large favorable habitats are known as stepping stones.

Hardy-Weinberg equilibrium equation:

p^2 + 2pq + q^2= 1

Together, solar energy and precipitation can be measured as....

potential evapotranspiration (PET)

Conservation

preservation, protection, or restoration of the natural environment, natural ecosystems, vegetation, and wildlife.

The current heterogeneity of habitats reflects...

recent and historical events caused by both natural forces and human activities

Changing tree distribution following the retreat of glaciers

records show that the composition of plant associations changed as species migrated back north over different routes across the landscape. The migrations of some representative tree species from their southern refuges are mapped in figure.

Botanists also recognize _______ major biogeographic regions, based on plant distributions, with boundaries that closely coincide with those regions based on animal distribution.

six

Smaller populations typically have higher extinction rates, therefore....

smaller populations typically have higher extinction rates. Therefore, smaller islands should experience higher rates of extinction, as shown by the curve labeled "Small" in figure.

Invasive Species

species that enter new ecosystems and multiply, harming native species and their habitats

Continental drift occurs because...

the continents are essentially giant islands of low-density rock that move by underlying convection currents of semi-molten material

The combined effects of island size and isolation on species richness. When we simultaneously consider island size and isolation, we find that the small islands that are far from a continent should have...

the lowest number of species at equilibrium (ŜSF), whereas large islands that are close to a continent should have the highest number of species (ŜLN).

Habitats

the natural home or environment of an animal, plant, or other organism.

Population Changes

the number of organisms of a species that can change due to competitors, predators, death, birth.

Renewable Resources

which can replenish to overcome usage and consumption, either through biological reproduction or other naturally recurring processes.

Succession

(ecology) the gradual and orderly process of change in an ecosystem brought about by the progressive replacement of one community by another until a stable climax is established

Legacy effects of humans on the landscape

(see image)

What are biodiversity benefits to society?

* Biodiversity's benefits to society include contributions to medicine and agriculture, and the provision of ecosystem goods and services. * Biodiversity provides direct and indirect economic benefits and maintains a healthy biosphere.

The complex weave of biodiversity is built of what 3 intertwined features?

* Ecosystem diversity * Species diversity * Genetic diversity ** The more intertwined these features, the denser and more resilient the weave becomes. Vital for the survival of organisms on Earth.**

Why is biodiversity important to ecosystems?

* It increases the stability of the ecosystem. * It helps populations adapt to ecological changes. * It helps populations adapt to ecological changes, which allows for a better chance to survive.

Choose two species: one that occurs throughout a large region and another that occurs only in a small region. What characteristics of these species or their environments might explain the difference in their distributions?

* Some species are generalists, tolerating a wide range of abiotic conditions, whereas others are specialists. * Some species live commensally with humans, which have generated global distributions of urban or agricultural habitats. * Some species disperse wide and far, whereas others have limited means of dispersal. * Some species are isolated by geographical factors such as islands in oceans, lakes within continents, or ice at the poles.

Ecosystem

A community of organisms interacting with one another and the non living environment.

The reduction in habitat size that comes with fragmentation commonly causes...

A decline in species diversity. This happens because each fragment supports smaller populations of species than existed in the original larger habitat and smaller populations experience higher rates of extinction.

Species accumulation curve

A graph of the number of species observed in relation to the number of individuals sampled.

Simpsons Index

A measure of species diversity formula weighted by the relative abundance of each species. (see image) 1/E(pi)squared ** We square each of the relative abundances values, sum these squared values, and then take the inverse of the sum.

Natural Disasters

A natural event such as a flood, earthquake, or hurricane that causes great damage or loss of life

Log-normal distribution

A normal, or bell-shaped, distribution that uses a logarithmic scale on the x-axis.

Biosphere

Consists of all life on Earth and all parts of the Earth in which life exists, including land, water, and the atmosphere.

True or False? From these results, one can conclude that plants from high elevation are more adapted to cold conditions than they are to warm conditions.

FALSE

True or False? The greater the distance between meadows, the more species should occur in each meadow.

False. Abiotic conditions contribute more to species richness than area and connectivity do.

To plot the data, Preston used...

To plot the data, Preston used the y-axis to represent the number of species and the x-axis to represent the number of individuals that comprise each species. **The key to visualizing the patterns of abundance in communities was to use categories of abundance.

Abiotic

physical rather than biological; not derived from living organisms.

Use Simpson's index to compare the diversity and evenness of species between communities.

1/E(pi)squared

Competition

A common demand by two or more organisms upon a limited supply of a resource; for example, food, water, light, space, mates, nesting sites.

Community

A group of interdependent organisms inhabiting the same region and interacting with each other

Population

A group of organisms of the same species populating a given area

local diversity or alpha diversity

Consider the number of species in a relatively small area of homogeneous habitat, such as a stream, we are looking at local diversity or alpha diversity.

A biome is characterized primarily by...

Climate and predominate plant types

Use the concepts of fragmentation and connectivity to compare different designs for a nature reserve.

Connectivity will allow for a nature reserve to be cohesive in that all species will be connected like in a natural habitat.

Quiz: Designing a Nature Preserve

Drag and drop (see image)

beta diversity

Ecologists refer to the number of species that differ in occurrence between two habitats as beta diversity. For example, imagine two streams in Vermont: Stream A contains five species not found in Stream B and Stream B contains three species not found in Stream A. Because the two streams differ by a total of eight species, the beta diversity is eight. The greater the difference in species between two habitats, the greater the beta diversity.

The Southern Hemisphere is divided into four biogeographic regions... Farther to the east is the ___________ region, also known as the __________ region, which includes India and Southeast Asia.

Indomalayan region (aka Oriental region)

Stability

Resisting to change.

Environmental Protection Laws

respecting pollution prevention and the protection of the environment and human health in order to contribute to sustainable development.

Ecologists in Vermont recently surveyed bird species along 27 streams that feed into Lake Champlain... They found waterbirds had their highest species richness and abundance in...

shallow streams


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