BIO 106 Test 2

Undernourishment

-After declining for four decades, the number and percentage of hungry people increased in 2008-2009. -Higher food prices and the economic slump. -The number of undernourished declined in 2010. -Hunger levels, as a percentage of population, are lower than in the 1970s.

Kwashiorchor

-Kwashiorkor: occurs when diet lacks protein or essential amino acids. -Occurs when children stop breast-feeding. -Bloated stomach, mental and physical disabilities.

Niche

-Latitudinal gradient: species richness increases toward the equator. -Equatorial regions have higher plant productivity, stable climates, and no glaciation. -Diverse habitats increase niches, which increase species diversity.

Marasmus

-Marasmus: is due to protein deficiency and insufficient calories. -Wasting of the body.

According to the theory of island biogeography, which island would have the LOWEST species richness?

D) A small island, far from the mainland.

Which level is NOT included in the concept of biodiversity?

D) All of the above are included in this concept.

A "biodiversity hotspot" is:

D) An area that contains a large number of endemic species.

Describe the relationship between growth rates and population size:

D) Falling growth rates does not mean a smaller population, but that rates of increase are slowing.

Where would ecotourists go to view the maximum species richness of these islands?

D) Hispaniola.

Insect success

Why are insects so successful? 1. Reproduce in large numbers. 2. Found everywhere - in every habitat. 3. Eat everything. 4. Extraordinarily resistent. 5. Extreme adaptable. 6. Move in many different ways. 7. Unbelievable camouflage.

Most populated cities:

•http://www.infoplease.com/ipa/A0763098.html

Traditional agriculture

-10,000 years ago, people in different cultures began to raise plants for food and to domesticate animals. -Agriculture: practice of raising crops and livestock for human use and consumption. -Cropland: land used to raise plants for human use. -Rangeland: land used for grazing livestock. -Land devoted to agriculture now covers 38% of Earth's land. -Traditional agriculture: uses human and animal power. -Hand tools, simple machines. -Polyculture: different crops are planted in one field. -Industrial agriculture: uses large-scale machines and fossil fuels to boost yields. -Also uses irrigation, fertilizers, and pesticides. -Monoculture: planting a single, genetically similar crop. -More efficient but reduces diversity, is disease prone. -Narrows the human diet. -Used in industrial agriculture. -The effects of industrialized agriculture: -Industrial agriculture has allowed food production to keep pace with population growth. -But it has many bad environmental and social effects. -Benefits: increases crop yields while reducing pressure to develop natural areas for new farms. -Drawbacks: water, fossil fuels, fertilizers, pesticides worsen pollution, erosion, and desertification. -Requires far more energy than traditional methods. -Displaces low-income farmers who can't afford the technology, forcing them to move to cities. -Sustainable agriculture: -Suitable farmland is disappearing. -We must improve the efficiency of production. -It is better to raise animals and crops that pollute less, require less fuels, and have less impact on natural systems. -Sustainable agriculture: maintains healthy soil, clean water, and genetic diversity. -Treats agricultural systems as ecosystems. -Low-input agriculture: uses smaller amounts of pesticide, fertilizers, growth hormones, antibiotics, water, and fossil fuels than industrial agriculture. -Soil: the foundation for agriculture. -Soil: a complex system consisting of disintegrated rock, organic matter, water, gases, nutrients, microorganisms. -A renewable resource that can be depleted if abused. -Soil contains: dead and living microorganisms, decaying material, bacteria, fungi, worms, insects, burrowing animals. -Soil influences ecosystems as much as climate, latitude, and elevation. -Parent material: the base geologic material of soil. -Lava, volcanic ash, rock, dunes. -Bedrock: solid rock comprising Earth's crust. -Weathering: physical, chemical, and biological processes that form that convert rocks into soil. -Biological deposition, decomposition, and accumulation provide organic matter and nutrients. -Humus: spongy, fertile material formed by partial decomposition of organic matter. -Holds moisture and is productive for plants. -A soil profile consists of horizons: -Horizon: each layer of soil. -Soil can have up to six horizons. -Soil profile: the cross-section of soil as a whole. -Leaching: movement of dissolved particles down through horizons. -Can deprive plants of nutrients. -Topsoil: inorganic and organic material most nutritive for plants. -Vital for agriculture. -Regional differences in soils affect agriculture: -In rainforests, rain leaches minerals and nutrients, reducing their accessibility to roots. -Rapid decomposition of leaf litter results in a thin topsoil layer with little humus. -Farming quickly depletes the soil's fertility. -Swidden agriculture: traditionally used in tropical areas. -After cultivation, a plot is left to regrow into forest. -Temperate prairies have lower rainfall and less nutrient leaching, resulting in higher fertility.

What is demography?

-All population principles apply to humans. -Environmental factors limit population growth. -The environment has a carrying capacity for humans. -Humans can raise the environment's carrying capacity through technology. -How many humans can the world sustain? 1-33 billion. -Population growth can't continue forever. -Demography: the application of population ecology to the study of human populations. -Population size. -Density and distribution. -Age structure, sex ratio. -Birth, death, immigration, and emigration rates. -Demographic transition: a model of economic and cultural change to explain the declining death and birth rates in industrialized nations. -Stable pre-industrial state of high birth and death rates changes to a stable post-industrial state of low birth and death rates. -Industrialization causes these changes. -As mortality decreases, there is less need for large families, and parents invest in quality of life. -Because of high birth rates and low death rates, population growth occurs. -In this model, population growth is seen as a temporary phenomenon as societies industrialize. -It has occurred in Europe, U.S., Canada, Japan, and other nations over the past 200-300 years. -But it may or may not apply to all developing nations. -The transition could fail in cultures that place greater value on childbirth or grant women fewer freedoms. -Fertility rates drop when women gain access to contraceptives, family planning programs, and better educational opportunities. -In 2007, 54% of married women worldwide used contraception. -China = 86%; the U.S. = 68%; 20 African nations < 10%

Anemia

-Anemia and deficiency in iodine and vitamin A are also prevalent.

Captive breeding programs

-Captive breeding: individuals are bred and raised with the intent of reintroducing them into the wild. -Zoos and botanical gardens. -Some reintroductions are controversial. -Ranchers opposed the reintroduction of wolves to Yellowstone National Park. -Some habitats are so fragmented, a species cannot survive. -Protecting biodiversity: -Cloning: a technique to create more individuals and save species from extinction. -DNA from an endangered species is inserted into an egg, which is implanted into a surrogate mother. -Most biologists agree that these efforts are not adequate to recreate the lost biodiversity. -Ample habitat and protection in the wild are needed to save species.

What is coevolution? (example: insects and flowers)

-Coevolution: evolution of hosts and parasites in response to each other. -They become locked in a duel of escalating adaptations. -Has been called an "evolutionary arms race". -Each evolves new responses to the other. -It may not be beneficial to the parasite to kill its host.

Characteristics of specific biomes:

-Community: an assemblage of species living in the same place at the same time. -Members interact with each other. -These interactions determine the composition, structure, and function of the community. -Community ecologists are people interested in how species coexist and relate to one another, how communities change, why patterns exist. -Around the world, communities share strong similarities. -Biome: a major regional complex of similar communities recognized by plant type, vegetation structure, and similar biomes occur at similar latitudes. -The biome in an area depends on a variety of abiotic factors. -Temperature, precipitation, ocean and air circulation, soil. -Climatograph: a climate diagram showing an area's temperature and precipitation. -Aquatic systems have biome-like patterns. -Various aquatic systems have distinct communities. -Coastlines, continental shelves. -Open ocean, deep sea. -Coral reefs, kelp forests. Coastal systems (marshes, mangrove forests, etc.) -Freshwater systems (lakes, rivers, etc.) -Aquatic systems are shaped by water temperature, salinity, and dissolved nutrients. -Wave action, currents, depth. -Substrate type and animal and plant life. -Temperate deciduous forest: -Deciduous trees loose their leaves each fall and remain dormant during winter. -Mid-latitude forests in Europe, East China, Eastern North America. -Fertile soils. -Forests: oak, beech, maple. -Temperate grasslands: -More extreme temperature difference between winter and summer. Less precipitation. -Also called steppe or prairie. -Once widespread throughout parts of North and South America and much of central Asia. -Much was converted for agriculture. -Bison, prairie dogs, antelope, and ground-nesting birds. -Temperate rainforest: -Coastal Pacific Northwest region. -Great deal of precipitation. -Coniferous trees: cedar, spruce, hemlock, fir. -Moisture-loving animals. -Banana slug -The fertile soil is susceptible to erosion and landslides. -Overharvesting has driven species to extinction and ruined human communities. -Tropical rainforest: -Central and South America, southeast Asia, west Africa. -Year-round rain and warm temperatures. -Dark and damp. -Lush vegetation. -Highly diverse species, but at low densities. -Very poor, acidic soils. -Nutrients contained in plants. -Tropical dry forest: -Tropical deciduous forest. -India, Africa, South America, northern Australia. -Wet and dry seasons. -Warm, but less rainfall. -Converted to agriculture. -Erosion-prone soil. -Savanna: -Tropical grassland interspersed with trees. -Africa, South America, Australia, India. -Precipitation only during rainy season. -Water holes. -Zebras, gazelles, giraffes, lions, hyenas. -Desert: -Minimal precipitation. -Some deserts are bare, with sand dunes (Sahara). -Some deserts are heavily vegetated (Sonoran). -They are not always hot. -Temperatures vary widely. -Saline soils ("lithosols"). -Nocturnal or nomadic animals. -Plants have thick skins or spines. -Tundra: -Canada, Scandinavia, Russia. -Minimal precipitation. -Nearly as dry as a desert. -Seasonal variation in temperature. -Extremely cold winters. -Permafrost: permanently frozen soil. -Few animals: polar bears, musk oxen, caribou. -Lichens and low vegetation with few trees. -Boreal forest (taiga): -Canada, Alaska, Russia, Scandinavia. -Variation in temperature and precipitation. -Cool and dry climate. -Long, cold winters. -Short, cool summers. -Poor, acidic soil. -Few evergreen tree species. -Moose, wolves, bears, migratory birds. -Chaparral: -Mediterranean Sea, California, Chile, and southern Australia. -High seasonal. -Mild, wet winters. -Warm, dry summers. -Frequent fires. Densely thicketed, evergreen shrubs.

Crop roation

-Crop rotation: growing different crops from one year to the next. -Returns nutrients to soil. -Prevents erosion, reduces pests. -Wheat or corn and soybeans. -Contour farming: plowing perpendicularly across a hill. -Furrows slow runoff and capture soil.

Starvation

-Decreased prey populations cause starvation of predators. -In 1970, China's 790 million people faced starvation. http://www.youtube.com/watch?v=mhetEdMlrH4

Genetically modified foods

-Despite the Green Revolution, relentless population growth demands more innovation to feed us. -Scientists alter genes of organisms. -Crop plants and livestock. -Genetically modified organisms enhance nutrition and agricultural efficiency. -But the risks are not well understood, leading to anxiety and protest from consumer advocates, small farmers, environmentalists, critics of big business. -Genetically modified organisms: -Genetic engineering: laboratory manipulation of genetic material. -Add, delete, modify DNA. -Genetically modified (GM) organisms: organisms that have been genetically engineered using recombinant DNA: DNA created from multiple organisms.

Ecotourism

-Ecotourism: people visit natural areas, creating economic opportunity for residents living near those areas. -Costa Rica: rainforests. -Australia: Great Barrier Reef. -Belize: reefs, caves, and rainforests. -A powerful incentive to preserve natural areas and reduce impacts on the landscape and species. -But too many visitors to natural areas can degrade the outdoor experience and disturb wildlife.

Endangered species

-Endangered Species Act (1973) (ESA): forbids the government and private citizens from taking actions that destroy endangered species or their habitats. -To prevent extinction. -Stabilize declining populations. -Enable populations to recover. -As of 2008, the U.S. had 1,046 species listed as endangered and 307 listed as "threatened."

Efforts to save animals:

-Endangered Species Act (1973) (ESA): forbids the government and private citizens from taking actions that destroy endangered species or their habitats. -To prevent extinction. -Stabilize declining populations. -Enable populations to recover. -As of 2008, the U.S. had 1,046 species listed as endangered and 307 listed as "threatened." -Despite opposition, the ESA has had successes: -Peregrine falcons, brown pelicans, bald eagles, and others have recovered and are no longer listed as endangered. -Intensive management has stabilized other species. -The red-cockaded woodpecker. -40% of declining populations are now stable. -These successes occur despite underfunding of the U.S. Fish and Wildlife Service and the National Marine Fisheries Service. -Recently, political forces have attempted to weaken the ESA. -In 2006, 5,700 U.S. scientists wrote letters of protest to Congress. -The ESA is controversial: -Most Americans support protecting endangered species. -Opponents feel that the ESA values endangered organisms more than the livelihood of people. -Private land use will be restricted if an endangered species is present. -"Shoot, shovel, and shut up": landowners conceal the presence of endangered species on their land. -But the ESA has stopped few development projects. -Habitat conservation plans and safe harbor agreements: landowners can harm species if they improve habitat for the species in other places. -Other countries have their own version of the ESA: -Species at Risk Act (2002): Canada's endangered species law. -Stresses cooperation between landowners and provincial governments. -Criticized as being too weak. -Other nations' laws are not enforced. -The Wildlife Conservation Society has to help pay for Russians to enforce their own anti-poaching laws.

Parasitism

-Exploitative interactions: a type of interaction where one species benefits while another is harmed. -Predation, parasitism, herbivory.

Predation

-Exploitative interactions: a type of interaction where one species benefits while another is harmed. -Predation, parasitism, herbivory. -Predation: process by which individuals of one species (predators) capture, kill, and consume individuals of another species (prey). -Structures food webs or food pyramids. -Influences community composition by determining numbers of predators and prey.

Predator: prey relationships

-Exploitative interactions: a type of interaction where one species benefits while another is harmed. -Predation, parasitism, herbivory. -Predation: process by which individuals of one species (predators) capture, kill, and consume individuals of another species (prey). -Structures food webs or food pyramids. -Influences community composition by determining numbers of predators and prey. -An example of predation: zebra mussels. -Zebra mussels prey on zooplankton. -Zooplankton decrease in lakes with zebra mussels. -Zebra mussels prey on phytoplankton. -Compete with zooplankton. Zebra mussels are becoming prey for some North American predators. -Ducks, fish, muskrats, crayfish. -Predation can drive population dynamics: -Increased prey populations increase predators. -Predators survive and reproduce. -Increased predator populations decrease prey. -Decreased prey populations cause starvation of predators. -Decreased predator populations increase prey populations. -Predation has evolutionary ramifications: Natural selection leads to evolution of adaptations that make predators better hunters. -Individuals who are better at catching prey live longer, have healthier lives, take better care of offspring. -Since prey are at risk of immediate death they develop elaborate defenses against being eaten.

Extinction

-Extinction: occurs when the last member of a species dies and the species ceases to exist. -Background rate of extinction: natural extinctions for a variety of reasons. -Mammal and marine species: 1 species out of 1,000 become extinct every 1,000 to 10,000 years, which translates to 1 extinction per 1-10 million species. -In the past 440 million years, mass extinctions have eliminated at least 50% of all species. -Dinosaurs went extinct at the end of the Cretaceous period (65 million years ago) from an asteroid impact. -During our modern era (Quaternary period), we may lose more than half of all species. -Today's extinction event differs from others because it is caused by humans, and humans will suffer because of it. -The current global extinction rate is 100 to 1,000 times greater than the background rate. -This rate will increase tenfold in future decades.

Extirpation

-Extirpation: the disappearance of a particular population from a given area, but not the entire species globally. -Can lead to extinction. -Paleontologists estimate 99% of all species are now extinct.

Food security

-Food security: guarantee of an adequate, safe, nutritious, and reliable food supply. -Providing food security to everyone will be one of our greatest challenges. -Indicators of hunger recently increased. -After declining for four decades, the number and percentage of hungry people increased in 2008-2009. -Higher food prices and the economic slump. -The number of undernourished declined in 2010. -Hunger levels, as a percentage of population, are lower than in the 1970s. -Undernutrition: receiving fewer calories than one's minimum dietary energy requirements. -925 million people do not have enough to eat. -Every 5 seconds a child starves to death is due to poverty, politics, conflict, and inefficiencies in distribution. -Over-nutrition: receiving too many calories each day. -Leads to heart disease, diabetes, etc. -In the U.S., 60% of adults are overweight, 25% are obese. -Worldwide, over 500 million people are obese. -These numbers will rise to 2.3 billion overweight and 700 million obese by 2015. -Malnutrition: a shortage of nutrients the body needs. -The diet lacks adequate vitamins and minerals. -Can lead to diseases.

Biodiversity

-Humans are diminishing Earth's diversity of life. -Biodiversity: sum total of all organisms in an area. -Split into three specific levels: Species diversity, genetic diversity, and ecosystem diversity. -Species diversity: the number or variety of species in the world or in a particular region. -Species richness: the number of species. -Evenness or relative abundance: extent to which numbers of individuals of different species are equal or skewed. -Speciation generates new species and adds to species richness. -Extinction reduces species richness. -Species richness is a good gauge for overall biodiversity. -Out of our "best guess" estimates of 5-30 million species on Earth, only 1.7-2 million species have been identified and described. What kind of animal need to be ID'd. -Very difficult to identify species: -Small organisms are easily overlooked. -Many species look identical until closely examined. -Many remote spots on Earth remain unexplored. -Biodiversity loss is more than extinction: -Population is declining. -Accompanied by shrinking geographic ranges. -Genetic, ecosystem, and species diversity are being lost. -The Living Planet Index summarizes trends in populations. -Between 1970 and 2003, the Index fell by 30%. -Biodiversity benefits: free ecosystem services: -Provides food, shelter, fuel. -Purifies air and water and detoxifies wastes. -Stabilizes climate, moderates floods, droughts, wind, temperature. -Generates and renews soil fertility and cycles nutrients. -Pollinates plants and controls pests and disease. -Maintains genetic resources. -Provides cultural and aesthetic benefits. -Allows us to adapt to change. -The annual value of just 17 ecosystem services = $16 - 54 trillion per year. -Biodiversity benefits: maintain ecosystem function: -Biodiversity increases the stability and resilience of communities and ecosystems. -Decreased biodiversity reduces a natural system's ability to function and provide services to our society. -The loss of a species affects ecosystems differently. -Extinction of a keystone species may cause other species to decline or disappear. -Biodiversity benefits: enhanced food security: -Genetic diversity in crops is enormously valuable. -Turkey's wheat crops received $50 billion worth of disease resistance from wild wheat. -New potential food crops are waiting to be used. -Serendipity berry produces a sweetener 3,000 times sweeter than sugar. -Salt tolerant grasses can be irrigated with seawater.

Resource partitioning

-In competitive relationships, each participant has a negative effect on the other participant. -To reduce competition, species can use a resource in slightly different ways. -Resource partitioning: when species divide shared resources by specializing in different ways. -Examples: one species is active at night, another in the daytime; one species eats small seeds, another eats large seeds.

Dead zone

-Inorganic fertilizers have boosted production. -But also severely pollute. -Leaching and runoff of inorganic fertilizers causes: -Groundwater contamination. -Dead zones in water systems. -Air pollution from evaporated nitrates. -Inorganic fertilizer use has skyrocketed worldwide

Irrigation

-Irrigation: artificially providing water to support agriculture. -Unproductive regions become productive farmland. -Waterlogging: water suffocates roots in overirrigated soils. -Salinization: the buildup of salts in surface soil layers. -Worse in dryland areas. -Salinization inhibits production of 20% of irrigated cropland, costing over $11 billion/year. -Sustainable approaches to irrigation: -Match crops and climate. -Don't plant water-guzzling crops in dry areas. -Plant beans or wheat, not rice. -Subsidies make irrigation water artificially cheap. -Drip irrigation delivers water directly to plants. -Drip irrigation works best on smaller plots with perennial plants (fruit trees).

Keystone species

-Keystone species: has a strong or wide-reaching impact far out of proportion to its abundance. -Removal of a keystone species has substantial ripple effects. -Alters the food web. -Keystone species can change communities. -Large-bodied secondary or tertiary consumers are often keystone species. -Extermination of wolves led to increased deer populations, which led to overgrazed vegetation and changed forest structure. -Reintroduction to Yellowstone very controversial. -Ecosystem engineers: physically modify the environment and exert strong community-wide effects. -Beaver dams, prairie dogs, fungi.

Mutualism

-Mutualism: a relationship in which interacting species benefit from one another. -Symbiosis: mutualism in which the organisms live in close physical contact. -Plant roots and fungi. -Coral polyps and algae (zooxanthellae) -Pollination: bees, bats, birds, and others transfer pollen from one flower to another, fertilizing its eggs. -Species may encounter each other infrequently. -Bees pollinate 73% of our crops. -Species interactions are the backbone of communities.

Vectors (vectors of parasites ie heart-worm)

-Parasite Transmission to Humans: 1. Active Penetration 2. Via Vectors 3. Through the mouth via the 4 F's

How do parasites enter a host? (3 methods)

-Parasites exploit living hosts: -Parasitism: a relationship in which one organism (parasite) depends on another (host) for nourishment or other benefit, while simultaneously harming the host. -Usually does not immediately kill the host. -Some species are free-living, and infrequently contact their hosts. -Cuckoos and cowbirds lay eggs in other birds' nests. -Many species live within the host. -Disease, tapeworms. -Other species live on the exterior of their hosts. -Sea lamprey. -Parasite Transmission to Humans: 1. Active Penetration 2. Via Vectors 3. Through the mouth via the 4 F's (fingers, flied, feces, flesh).

What disease kills more people than any other?

-Parasitism: a relationship in which one organism (parasite) depends on another (host) for nourishment or other benefit, while simultaneously harming the host. -Usually does not immediately kill the host. -Some species are free-living, and infrequently contact their hosts. -Cuckoos and cowbirds lay eggs in other birds' nests. -Many species live within the host. -Disease, tapeworms -Other species live on the exterior of their hosts. -Sea lamprey.

IPAT

-Population growth affects the environment: -The IPAT model: I = P x A x T -Our total impact (I) on the environment results from the interaction of population (P), affluence (A), and technology (T).

What factors contribute to a growing human population?

-Population growth results from technology, medical care, sanitation, and food. -Death rates drop, but not birth rates. -Some people say growth is no problem. -New resources will replace depleted ones. -But some resources (i.e., biodiversity) are irreplaceable. -Quality of life will suffer with unchecked growth. -Less food, space, wealth per person. -Some people fear falling populations: -Population growth is correlated with poverty, not wealth. -Policymakers believe growth increases economic, political, and military strength. -They offer incentives for more children. -67% of European nations think their birth rates are too low. -In non-European nations, 49% feel their birth rates are too high. -Population growth affects the environment: -The IPAT model: I = P x A x T -Our total impact (I) on the environment results from the interaction of population (P), affluence (A), and technology (T). -Population: individuals need space and resources and produce waste. -Affluence: per capita resource use. -Technology: allows increased exploitation of resources • But can also reduce our impact (e.g., decrease emissions). -Further model refinements include: sensitivity of the environment to impacts, education, laws, ethics. -Whether a population grows, shrinks, or remains stable depends on rates of birth, death, and migration. -Birth and immigration add individuals. -Death and emigration remove individuals. -Technological advances led to dramatic decline in human death rates. -Widening the gap between birth rates and death rates resulting in population expansion. -Falling growth rates do not mean a decreasing population, but only that rates of increase are slowing. -Total fertility rate (TFR): the average number of children born per female. -Replacement fertility: TFR that keeps the size of a population stable. -For humans, replacement fertility = 2.1. -Urbanization decreases TFR. -Access to medical care. -Children attend school and impose economic costs. -With social security, elderly parents need fewer children to support them. -Greater education allows women to enter the labor force, with less emphasis on child rearing.

Carrying capacity

-Population size and density: -Nobody knows the ultimate human population size. -But numbers are not the only important aspect. -Highest population density is in temperate, subtropical, and tropical biomes. -Density increases near coasts, waterways, and cities. -Predictions of population size depend on different assumptions about fertility rates. -Increased density impacts the environment, but relieves pressure in less-populated areas. -Humans are unevenly distributed around the globe. -Unpopulated areas tend to be environmentally sensitive (i.e., deserts). -Many populations are getting older. -Older people need care and financial assistance. -But also reduces the number of dependent children and crime rates.

Human population statistics: world, U.S., cities

-Populations continue to rise in most countries. -Particularly in poverty-stricken developing nations. -Although the rate of growth is slowing, we are still increasing in absolute numbers. -It would take 30 years, counting once each second, to count to a billion. -Human population growth: 7.4 billion. -It took all of human history up to approximately 1850 reach 1 billion. -In 1930, 80 years later, we reached 2 billion, and added the most recent billion in 12 years. -We add 80 million people each year (2.5 people/second). -Due to exponential growth, even if the growth rate remains steady, population will continue to grow. -At today's 1.2% global growth rate, the population will double in 58 years (70/1.2 = 70). -If China's rate continued at 2.8%, it would have had 2 billion people in 2004. -Every European nation now has a TFR < replacement level. -Natural rate of population change: population change due to birth and death rates alone. -In countries with good sanitation, health care, and food, people live longer. (They have a higher life expectancy.) -Many countries provide incentives, education, contraception, and reproductive health care. -Funding and policies that encourage family planning lower population growth rates in all nations. -Thailand has an educational based approach to family planning and its growth rate fell from 2.3% to 0.7%. -Brazil, Mexico, Iran, Cuba, and other developing countries have active programs. -In 1994, in Cairo (Egypt), 179 nations called on all governments to offer universal access to reproductive health care within 20 years. -Offer better education and health care and alleviate poverty, disease, and sexism. -From 1998 to 2001, the U.S. provided $46.5 million to the United Nations Population Fund for family planning efforts. -George W. Bush cancelled funding as one of his first acts on becoming U.S. president in 2001. -Poorer societies have higher growth rates than wealthier societies. -Consistent with the demographic transition theory. -They have higher fertility and growth rates, with lower contraceptive use. -Poverty results in environmental degradation. -99% of the next billion people added will be born in poor, less-developed regions that are least able to support them. -The population problem does not exist only within poor countries. -Affluent societies have enormous resource consumption and waste production. -People use resources from other areas, as well as from their own. -Individuals' ecological footprints are huge. -One American has as much environmental impact as 6 Chinese or 12 Indians or Ethiopians. -The stark contrast between affluent and poor societies causes social and environmental stress. -The richest 20% use 86% of the world's resources. -Leaves 14% of the resources for 80% of the world's people to share. -Tensions between "haves" and "have-nots" are increasing. -If developing countries cannot overcome their increasing social, economic, and environmental problems, and if developed nations do not help then these countries may not advance through the demographic transition, and instead will result in greater population growth, and worsening social and environmental conditions. -A profoundly negative outcome for humans and the environment.

Primary succession

-Primary succession: disturbance eliminates all vegetation and/or soil life. -A community is built from scratch. -Glaciers, drying lakes, volcanic lava. -Pioneer species: the first species to arrive in a primary succession area (i.e., lichens). -New organisms arrive, increasing vegetation and diversity.

What are the reasons for biodiversity loss?

-Reasons for biodiversity losses are multifaceted, complex, and hard to determine. -Four primary causes of population decline are: habitat alteration, invasive species, pollution, and overharvesting. -Global climate change now is the fifth cause. -Each factor is intensified by human population growth and resource consumption. -The greatest cause of biodiversity loss: -Farming simplifies communities. -Grazing modifies grassland structure and species composition. -Clearing forests removes resources that organisms need. -Hydroelectric dams turn rivers into upstream reservoirs and affect floodplains downstream. -Urbanization and suburban sprawl reduce natural communities. -A few species (i.e., pigeons, rats) benefit from changing habitats. -Less than 1% of North America's Great Plains remains, and grassland bird populations have declined 82-99%. -Invasive species cause biodiversity loss: -Introduction of non-native species to new environments: -Accidental: zebra mussels. -Intentional: food crops. -Island species haven't evolved defenses and are very vulnerable. -Invaders have no natural predators, competitors, or parasites. -Cost billions of dollars in economic damage each year. -Pollution causes biodiversity loss: -Harms organisms in many ways. -Air pollution degrades forest ecosystems. -Water pollution adversely affects fish and amphibians. -Agricultural runoff harms terrestrial and aquatic species. -The effects of oil and chemical spills on wildlife are dramatic and well known. -Although pollution is a substantial threat it tends to be cause less damage than habitat alteration or invasive species. -Overharvesting causes biodiversity loss: -Vulnerable species are large, few in number, long-lived, and have few young (K-selected species). -The Siberian tiger is hunted without rules and regulations. -The early 1990s saw increased tiger poaching because of powerful economic incentives. -Many other species affected: Atlantic gray whale, sharks, gorillas, black bear. -Today the oceans contain only 10% of the large animals they once did. -Climate change causes biodiversity loss: -Our manipulation of earth's climate system is having global impacts on biodiversity. -Emissions of greenhouse gases warm temperatures. -Modifies global weather patterns and increases the frequency of extreme weather events. -Increases stress on populations and forces organisms to shift their geographic ranges -Most animals and plants will not be able to cope. -Biodiversity benefits: economic benefits: -Biodiversity provides a source of income through tourism.

Read pages on zebra muscles: invasive species

-Small, black and white shellfish native to western Asia and eastern Europe. -Introduced in 1988 to Lake St. Clair, Canada, in discharged ballast water. -By 1994, zebra mussels had invaded all 5 Great Lakes, the Mississippi river, 19 U.S. states, and 2 Canadian provinces. -No natural predators, competitors, or parasites -These mussels cost the U.S. economy hundreds of millions of dollars of damage to property each year. -They also cause enormous ecological damage. -Invasive species: non-native (exotic) organisms that spread widely and become dominant in a community. -Can substantially alter a community -Growth-limiting factors (predators, disease, etc.) are removed or absent. -They have major ecological effects. -Fish introduced for sport outcompete and exclude native fish. -Some species help people (i.e., European honeybee). Techniques to control invasive species: -Remove manually. -Toxic chemicals - Lamprey in Great Lakes. -Drying them out. -Depriving of oxygen. -Introducing predators and diseases. -Stressing them -Heat, sound, electricity, carbon dioxide, ultraviolet light. -Prevention, rather than control, is the best policy.

Erosion

-Soil erosion: -Soil degradation: loss of soil quality and productivity. -Has caused 13% loss of grain production. -Each year, we lose 12-17 million acres of cropland. -Erosion, nutrient depletion, water scarcity, salinization, water-logging, pollution, loss of organic matter. -Erosion: removal of material from one place to another. -By wind or water. -A problem when it happens faster than soil formation. -Deposition: arrival of eroded material at a new place. -Humans make land vulnerable to erosion: -Land is made vulnerable to erosion through: -Over-cultivating fields - poor planning, excessive tilling. -Overgrazing rangeland with too many animals. -Clearing forests on steep slopes or with large clear-cuts. -Erosion removes valuable topsoil, especially in areas with steeper slopes, greater precipitation intensities, and sparse vegetation. -Soil erosion is a global problem: -Humans are the primary cause of erosion. -It is occurring at unnaturally high rates. -In Africa, erosion could reduce crop yields by 50% over the next 40 years. -The U.S. loses 5 tons of soil for every ton of grain harvested. -Degradation of topsoil and decreased crop yields, added to population growth are leading agriculture's future to a crisis situation.

Secondary succession

-Succession: the predictable series of changes in a community following a disturbance. -Secondary succession: a disturbance dramatically alters, but does not destroy, all local organisms. -Parts of the previous community remain and serve as "building blocks." -Fires, hurricanes, farming, logging. -Climax community: the community resulting from successful succession. -Remains stable until another disturbance restarts succession -Community change is variable and unpredictable. -Conditions at one stage may promote progression to another stage. -Organisms, through competition, may inhibit progression to another stage. -Other factors (e.g., soil conditions) also help determine communities.

Terracing

-Terracing: level platforms cut into steep hillsides. -This "staircase" contains rain and irrigation water. -Intercropping: planting different crops in alternating bands. -Increases ground cover. -Decreases pests and disease. -Replenishes soil. -Protecting soil: shelter-belts and reduced tillage. -Shelter-belts (windbreaks): rows of trees planted along edges of fields. -Slows the wind. -Can be combined with intercropping. -Tillage: reduces the amount of tilling. -No-till farming disturbs the soil even less.

Red list

-The Red List: an updated list of species facing high risks of extinctions. -22% of mammal species. -12% of bird species. -16-86% of all other species. -Since 1970, 58 fish species, 9 bird species, and 1 mammal species have gone extinct in the U.S. in the last 500 years, 236 animal and 17 plant species are confirmed extinct. -Actual numbers are undoubtedly higher. -Categories of Red List: -Species are classified in nine groups, set through criteria such as rate of decline, population size, area of geographic distribution, and degree of population and distribution fragmentation. -Red list categories: 1.Critically Endangered (CR) - Extremely high risk of extinction in the wild. 2.Extinct (EX) - No individuals remaining. 3. Extinct in the Wild (EW) - Known only to survive in captivity, or as a naturalized population outside its historic range. 4. Endangered (EN) - Very high risk of extinction in the wild. 5. Vulnerable (VU) - High risk of extinction in the wild. 6. Near Threatened (NT) - Likely to become endangered in the near future. 7. Least Concern (LC) - Lowest risk. Does not qualify for a more at risk category. Widespread and abundant taxa are included in this category. 8. Data Deficient (DD) - Not enough data to make an assessment of its risk of extinction. 9. Not Evaluated (NE) - Has not yet been evaluated against the criteria. -When discussing the IUCN Red List, the official term "threatened" is a grouping of three categories: Critically Endangered, Endangered, and Vulnerable.

Transgenics

-The goal of genetic engineering: put genes that code for desirable traits (rapid growth, nutrition, etc.) -Into organisms lacking those traits. -Transgenic organism: an organism that contains DNA from another species. -Transgenes: the genes that have moved between organisms. -Biotechnology: the application of biological science to create products derived from organisms. -It has created medicines, cleaned up pollution, dissolved blood clots, and made better food.

Levels of taxonomy: (from lab)

1. Kingdom 2. Phylum 3. Class 4. Order 5. Family 6. Genus 7. Species

Which statement about the U.S. Endangered Species Act is FALSE?

A) It forbids the government, but not private citizens, from harming endangered species.

According to the concept of "latitudinal gradient", which of the following happens?

A) Species richness increases toward the equator.

Which biome lost the most area by 1950? Which biome lost the most area in recent decades?

A) Temperate grassland, tropical dry forrest.

How have humans been able to raise the environment's carrying capacity for our species?

A) Through technology.

Would you rather live in a country with a larger population or a smaller population?

Any. A) Small population, so there will be more resources for me. B) Small population, so there will be more resources for others, including wildlife. C) Large population, so I can find a date. D) Large population, because people are our biggest resource.

If a pharmaceutical company produces a medicine from a plant found in Costa Rica that will earn millions of dollars, who would reap the financial benefits?

Any. A) The company, because it had to pay millions of dollars to discover and produce the drug. B) Costa Rica, because it had the plant that produced the drug. C) Taxpayers, because they fund lots of research through their tax dollars. D) Native people in Costa Rica, because the company would not have found the drug without their help. E) The native people, the company, and Costa Rica, because all played a vital part in the drug's discovery and development.

A fear of fewer workers and a weakened economy has led many policymakers in developed countries to offer incentives to women to have more children.

Any. A) This is good, since children strengthen society. B) This is good, since developed nations can afford larger populations. C) This is not good. Developed nations can increase immigration to increase workers. D) This is not a good idea. Leaders must find other solutions. E) I don't care, since I plan on living in the U.S. anyway.

Have you ever personally experienced evidence of a biophilia hypothesis?

Any. A) Yes, I frequently feel a connection to other living things and nature. B) Yes, sometimes, on a particularly lovely day. C) Maybe, but I'm not sure. D) No, because I don't get to experience nature often enough. E) Definitely not, unless I was going to earn money from using nature.

In 2001, the Bush administration withheld funds for international family planning. Should the U.S. fund family planning?

Any. A) Yes, absolutely. B) Yes, but only in nations that follow U.S.-approved programs. C) Only if it can influence the nation's policies. D) Never under any circumstances. It's not our job. E) No, we are too broke to help other nations.

What has accounted for the majority of the world's population growth in recent years?

B) Death rates have dropped due to technology, medicine, and food.

Biodiversity does all of the following EXCEPT:

B) Decrease food security.

What happens when a species experiences "inbreeding depression"?

B) Genetically similar parents mate and produce inferior offspring.

What are the problems with ethanol?

Biofuels can affect food supplies: -Biofuels: fuels derived from organic materials. -Replace petroleum in engines. -Ethanol: a biofuel derived from corn. -The main biofuel in the U.S. -2007 subsidies doubled U.S. production. -Use of corn for biofuel reduced corn supplies. -Food prices increased. -Farmers sold corn for ethanol, not food. -Farmers planted biofuels, not food crops. -Riots erupted in many nations.

Biophilia

Biophilia: connections that humans subconsciously seek with life. -Our affinity for parks and wildlife. -Keeping of pets. -High value of real estate with views of natural lands. -Nature deficit disorder: alienation from the natural environment. -May be behind the emotional and physical problems of the young.

Which of the following is the major cause of extinction?

C) Habitat loss.

What happens during the "transitional" stage of the demographic transition?

C) High birth rates with low death rates cause population to increase.

According to this age pyramid, Madagascar's future population will be:

C) Much larger.

Areas that lack significant numbers of people and have a low population density are:

C) Sensitive areas least able to support high densities of people.

According to the I =P x A x T formula, what would happen if the U.S., with its consumptive lifestyle, increased its population to 1 billion people?

C) The impact of the environment would increase.

Which of the following statements is FALSE?

C) We have identified almost all species on earth.

What will keep a population size stable?

C) When TFR = replacement fertility.

Chinese and population reduction

Case study: China's one-child policy: -In 1970, China's 790 million people faced starvation. -The average Chinese woman gave birth to 5.8 children. -The government instituted a one-child policy. -China's growth rate plummeted. -The government first used education and outreach and later instituted rewards and punishments. -In 1984, the policy exempted ethnic minorities and farmers. -The program has been both successful and controversial. -The low growth rate makes it easier to deal with challenges. -It has produced unintended consequences: killing female infants and a black-market trade in teenage girls.

No-till farming

Central Case Study: Iowa's Farmers Practice No-Till Agriculture: -Repeated plowing and planting damage soil. -No-till farming benefits soil. -Saves time and money. -Does not decrease production. -Can help make agriculture sustainable. -Other conservation measures: -Careful use of fertilizers. -Preventing erosion. -Retiring fragile soils.

Which of the following will NOT result in lower population growth rates?

E) All of these result in lower population growth rates.

The 4 F's:

Parasite Transmission to Humans: 1. Active Penetration 2. Via Vectors 3. Through the mouth via the 4 F's FINGERS FLIES FECES FLESH