Biol421 test 1

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What does your textbook propose as the three guiding principles of Conservation Biology? Briefly discuss each.

1) Evolution is the basic axiom that unites all of biology (the evolutionary play) Evolution is the only reasonable mechanism able to explain the patterns of biodiversity (2) The ecological world is dynamic and largely non-equilibrial (the ecological theater) Ecosystems are open to the exchange of materials and species and to the flux of energy No long-term stable points (3) Human presence must be included in conservation planning (human presence) "Indigenous knowledge" that residents hold about local natural history is useful in developing protected area management plans; important role as staff "User friendly" builds public support; formal and informal educational programs Native human cultures are a historical part of natural history and the ecological landscape; adds cultural and linguistic diversity

Franklin et al 2002 suggest that it is important to correctly categorize how habitat is being altered, what 4 cases do they distinguish?

1:Habitat loss without fragmentation. 2:Habitat loss with fragmentation. 3: Fragmentation. 4: Edge effects, fragmentation, change in habitat quality.

Brook et al (TREE 2008) present different models of how individual threats can lead to biodiversity loss. Briefly describe the different potential relationships between threatening processes as presented by these authors. You can use a simple graph to present your ideas.

3 factors: habitat loss, harvesting, and climate change. Fully additive: each of the factors do not affect each other at all. Partial additive: Species is vulnerable to 1 factor, but already went extinct to a combination of the other 2 factors. Synergy: Lose even more species because of a combined effect on vulnerability on all three threats.

Approximately how many humans are on the planet today? What is the historical trajectory of human population growth and how does this relate to the field of Conservation Biology?

7.5 billion humans currently. UN predicts by 2050 9.7 billion The human population is growing so fast that we are causing the 6th mass extinction.

How are alpha, gamma, and beta diversity estimated? What do these measures tell us about how diversity is spatially distributed and how might they be used in conservation planning?

Alpha- species richness, local focus area. Count the number of species in the focus area and take the average. Mtn example, from class. Gamma- total number of species across larger area that encompasses individual focal areas- regional perspective of species count. Mtn example. Beta- Metric of turnover from spot A to spot B. Community variation from mtn range 1 to mtn range 2. Gamma/alpha.

What is the Allee effect? Provide a brief example of such an effect in a population.

Allee effects are broadly defined as a decline in individual fitness at low population size or density, that can result in critical population thresholds below which populations crash to extinction.

Why is alpha taxonomy, the description and naming of species, important in conservation biology?

Alpha taxonomy is used to classify organisms hierarchically in ways that reflect their evolutionary history. Classifications are constructed in which the higher taxonomic categories contain all of the descendants on their most recent ancestor, but no other species (monophyletic).

How did the Aral Sea change in size from 1964 to the late 2000s? Why did this change occur? List at least 4 biological, ecological, or commercial/economic outcomes of this change.

Aral sea was dried out, because it lost its primary water inlet. Water was diverted to sustain a cotton industry. This led to 60% of human population losing drinking water. Led to collapse of fishing, cotton, and meat industries. Collapse of aquatic species due to increasing salinity. Higher concentration of minerals in water.

Where will most of the changes in our current understanding of taxonomic diversity come, that is, which groups are currently the most poorly described?

Bacteria, only .5% described. VIruses, 1% described Fungi, 5% described Nematoda, 6% described

According to research done by Dr. Tyrone Hayes, how does the pesticide atrazine impact individual frogs at various developmental stages and what are the population-level implications?

Atrazine shrinks reproductive organs, and produces a teste/ovary tissue. Frogs become hermaphroditic, males stopped producing testosterone, and feminized. Caused a low reproductive output. This was at levels of atrazine found in normal water.

Conservation biology is often viewed as a "crisis-discipline". List three characteristics of the discipline that accompany this description. Name at least one benefit and one drawback of continuing to promote Conservation Biology as a "crisis-discipline".

Crisis discipline Tolerate uncertainty: may have to make decisions with limited data. Emergency decision making. Recognizing problems late Lack policy and regulation. Problems with being in crisis mode= mistakes are made, good science is not done in haste. Benefit: We cannot prevent every crisis so it is good to have a discipline to fall back on rather than having nothing at all.

From Soule 1985, what are at least 3 primary defining characteristics of the field of Conservation Biology? Provide a brief statement describing each.

Crisis discipline Tolerate uncertainty: may have to make decisions with limited data. Emergency decision making. Recognizing problems late Lack policy and regulation. Problems with being in crisis mode= mistakes are made, good science is not done in haste. Holistic Multidisciplinary Multispecies Timescale Evolutionary, not just current but how populations, species, communities will make it through time. Natural Resource Management Not just economically important species.

Provide a succinct definition of "edge effects". List four environmental or biological characteristics that might differ between edge and core habitat.

Diverse physical and biological phenomena associated with abrupt, artificial boundaries of habitat fragmentation. Changes in microclimate, exposure to disturbance , alter predator prey relationships, allows for spread of disease and invasive species.

Briefly describe the Tilman experiments we discussed in lecture and what they tell us about 'diversity-stability' and 'diversity-function'.

Diverse plots are stable, and vary less over time. Diverse plots increase biofuel. Plots with 2,4,8,16 species increased biofuel production 84, 100, 157, 238% more than monoculture. Experiment created plots on depleted soil, in various plots, with more or less species. Positive relationship between richness and carbon sequestering.

What are the hierarchical levels in which diversity is organized and which level receives most attention in conservation? Do you see that particular focus as a strength or weakness, why?

Ecosystem, Community, Species, Population, Gene The species level receives the most attention in conservation because they are the fundamental components of biodiversity. The focus on species is both a strength and a weakness. Species diversity contributes so much to the natural world. If we lose focus on species, there is almost no point to conservation. A human-centered world will not survive without species diversity. Each hierarchical level supports the other. If we place too much focus on one level we may lose critical insight from the others which could potentially help us strengthen species diversity.

Describe several ways that biodiversity hotspots have been identified in the literature highlighted in lecture, what is the cautionary suggestion from Ceballos and Erlich 2008?

Endemism Richness Threat Level Shouldn't focus on just one area for conservation. Should be able to prioritize in all different ways that conserve the most.

In the Channel Island example we discussed in class, how would you answer the high school teacher's question : Why the pig? Provide at least 4 points.

Fox is native, endemic, keystone species that co-evolved with island communities. Pig is a strong interactor. Bottom up/top down effects. Pig is widespread. Pig has no natural predator, not co-evolved with island communities. Fox is evolutionarily distinct. Fox is more aesthetically pleasing/charismatic (flagship species)

From examination of past extinction events, there appear to be at least some life history/ecological traits that contribute to extinction risk. Name 4 of these and their general relationship with extinction risk. Feel free to use simple graphs with labeled axes to present your ideas. List at least one species that exemplifies each of life history or ecological traits you describe.

Geographic range. If you have a small range, you are likely to go extinct. Home range, if you need a large, uninterrupted tract of land to do stuff in, you are likely to go extinct. Population density; a large, dense population is less likely to go extinct. Trophic level; higher trophic levels are likely to go extinct. Specialization; specialized species are more likely to go extinct.

Describe an indirect ecosystem service and what would have to be put in place by humans to replace this service

Indirect-Water storage and recharge, water filtration, nutrient cycling, flood attenuation, microclimate buffering. Can be replaced by: large water treatment plants, large composting, levees, adapting to new microclimates.

What does the Rarity-Weighted Richness Index aim to capture in terms of overall biodiversity and how would this measure help you prioritize your conservation efforts?

It combines alpha and beta diversity into a single number and weighs the level of rarity for the species in the area. Areas with a larger RWRI should be prioritized higher for conservation efforts.

Why does the shape of the 'diversity-function' relationship matter in terms of the consequences of biodiversity loss?

It is important because it creates a barometer of sorts, that can be used to predict how many species can be lost before the function of the ecosystem will be changed.

Provide a succinct definition of habitat fragmentation.

Large expanse of habitat, transformed into smaller, isolated areas, unlike original. Discontinuity of resource distribution that affects survival of species.

We discussed 4 hypothetical relationships between species richness (as a measure of diversity) and ecosystem function. Graph them and provide a brief interpretation of each.

Linear: Richness increases as function increases, and vice versa. The least probable relationship. Rivet: Richness does not increase until it hits a certain level of function. Redundancy: Richness evens out when function is at its peak. Idiosyncratic: Richness and function show no discernable pattern.

What is the difference between habitat loss and habitat degradation?

Loss in impacts so severe that all species are somehow impacted. Degradation impacts some species, not all species, with the eventual possibility to restore the area.

Tillman showed that ecosystems with higher species richness are more stable. Why might diverse ecosystems be more stable over time?

Loss of species influences instability in a negative feedback loop. It is possible that high richness will include species that encourage redundancy and stability. Diverse communities use a resource completely, meaning less resources for the invasive species to use.

Why is it important to consider edge effects in assessing habitat availability?

Most pervasive and damaging effects on biota came from edge effects. Matrix can exacerbate edge effects.

ist 4 ways in which habitat fragmentation differs from natural heterogeneity.

Natural landscapes are divided into patches; diversity in habitats are in dynamic equilibrium, species may nor not be able to adjust to rapid change. Patches and matrix in natural habitats tend to have complex internal structure, matrix tends to be simplified. Contrasts are more intense in fragmented habitats.

Draw the classic ETIB model as presented by MacArthur and Wilson with labeled axes and rates of colonization/extinction in small/large islands, near/far from the mainland.

No

What is a "patch"? What is the "matrix"?

Patch is a native habitat, that is undeveloped. Matrix is entirely inhospitable, outside area of patch.

What do McGarigal et al. (2005) suggest are the characteristic steps in the progression of habitat fragmentation? Briefly describe each.

Perforation: small holes of development. Dissection: connecting small holes with roads and other development. :subdivision: Habitat becoming physically subdivided. Shrinkage and attrition: Each group of development consistently increases area of development.

Describe two ways of quantifying habitat fragmentation and what characteristics of fragmented habitat they are intended to reflect.

Proximity index- accounts for diversity, patch distance. Able to see connectedness of system. Down Weights isolation. Px=sum(Si/Zi) Edge to area ratio- length of edge/area of area. Does not count isolation distance, considers patch shape and size

From the basic ETIB model, compare species richness and turnover rates in small-far and large-near islands.

Small-far island will have the lowest number of species, and an intermediate rate of turnover. Large near islands will have the largest number of species, with an intermediate number of turnover.

Name and describe three major schools of thought that have shaped American conservation biology since the 1800's. Provide the name of at least one person that is associated with each.

Romantic/Transcendental Emphasized the spiritual and aesthetic value of nature and "wildlife" Mid 1800 writers: Ralph Waldo Emerson- A connection with nature is essential for a person's intellectual, aesthetic, and moral health and growth. Basis of self-reliance and how a person lives with integrity in nature and society. Henry David Thoreau- "I went to the woods because I wished to live deliberately, to front only the essential facts of life, and see if I could not learn what it had to teach, and not, when I came to die, discover that I had not lived." Simple living in the natural environment. John Muir- first president of the Sierra Club. Influenced creation of national parks. Resource Conservation Ethic The efficient, scientifically-informed management of nature for human benefit. "Multiple-use" Theodore Roosevelt- 1901 became president. Set aside ~230 million acres as National Parks, National Forests, bird and game reserves, and National Monuments. Evolutionary Ecological Land Ethic Natural communities are worth preserving without reference to any derived human benefits. Aldo Leopold- Beginning of modern conservation biology. "The biota as a whole"

What do these measures tell us about how diversity is spatially distributed?

Simple approach for conservation planning: Protect areas w/highest alpha diversity. Add areas in order of how many new species they add, maximizing beta diversity. RWRI- combines alpha and beta diversity.

What three key pieces of information did MacArthur and Wilson have in hand as they began to develop their ETIB?

Species area relationship, species isolation, species turnover

What is a keystone species and what does the concept suggest about how communities are structured?

Species on which other species depend on, if it were removed, the ecosystem would collapse. Suggests certain species have huge impact on rest of ecosystem. Top predators, ecosystem engineers, pollinators.

Compare and contrast the three major schools of thought that shaped American conservation biology since the 1800's.

The Romantic and Resource Conservation Ethic are both essentially human centered, the environment is worth something because it provides humans with some benefit. Whereas, the Evol Eco Land Ethic is centered around preserving these natural communities because they are worth it without offering a benefit to humans.

What is a succinct definition of biodiversity?

The number (species richness) and relative abundance of units at each level of the hierarchy of life

What is an extinction debt and how does the species-area relationship contribute to estimates of extinction debt? Use a graph of this relationship to present your answer.

There is a large amount of habitat destruction, without associated extinction. Eventually that population will go extinct.

What habitat/region(s) are projected to experience the most habitat loss by 2050 and why is this of particular significance to biodiversity?

Tropical, subtropical coniferous forest. Tropical grassland. Tropical, broadleaf forest. This is bad, because these areas have the highest levels of biodiversity.

What does the Shannon Index aim to capture in terms of overall biodiversity and how would this measure help you prioritize your conservation efforts?

What does the Shannon Index aim to capture in terms of overall biodiversity and how would this measure help you prioritize your conservation efforts?


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