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Unit 5 What is Ecology and How is it Impacted by Human? What is Ecology? Ecology These interactions determine ___________________ of organisms and their __________________________ For example The rediscovery of the nearly extinct harlequin toad in Costa Rica raises many ecological questions What environmental factors limit their geographic distribution? What factors (food, pathogens) affect population size? The Scope of Ecological Research Ecologists work at levels ranging from ___________________ organisms to the ___________________ Global Ecology The __________________ is the global ecosystem, the sum of all the planet’s ecosystems ______________________ ecology examines the influence of energy and materials on organisms across the biosphere Landscape Ecology A ______________________ or ___________________ is a mosaic of connected ecosystems _________________________ ecology focuses on the exchanges of energy, materials, and organisms across multiple ecosystems Ecosystem Ecology An ______________________ is the community of organisms in an area and the physical factors with which they interact Ecosystem ecology emphasizes energy flow and chemical cycling among the various ___________ and __________________ components Community Ecology A _______________________ is a group of populations of different species in an area ________________________ ecology deals with the whole array of interacting species in a community Population Ecology A __________________ is a group of individuals of the same species living in an area __________________ ecology focuses on factors affecting population ___________ over time Organismal Ecology ____________________ ecology studies how an organism’s structure, physiology, and (for animals) behavior meet environmental challenges With this heirarchy you will note that all areas of biology discussed this semester is integrated in ecological studies For example, Ecologists ask questions about where species occur and why species occur where they do? How do environmental factors explain distribution of organisms? Both _________________ and ___________________ factors influence species distribution For example, climate, interspecific interactions, and other factors affect the distribution of the red kangaroo Biotic Factors Biotic factors that affect the distribution of organisms may include _______________________ _______________________ For example, sea urchins can limit the distribution of seaweeds _______________________ Abiotic Factors Abiotic factors affecting distribution of organisms include _________________________ Cells may freeze and rupture below 0°C, while most proteins denature above 45°C _____________________ and ______________________ desert vs rainforest; deep vs shallow _____________________ _____________________ _____________________ _________________ and _____________________ Limit vegetation thus limits animals Most abiotic factors vary in space and time What is Population Ecology? Population ecology is Density, Dispersion Patterns and Demographics are Important Population Variable A ______________________ is a group of individuals of a single species living in the same general area Populations are described by their _____________________ and ___________________ Density Density is In most cases, it is impractical or impossible to count all individuals in a population Population size can be estimated by either extrapolation from small samples, an index of population size (e.g., number of nests), or the __________________________________ ___ = # of individuals captured tagged and released in first sample ___ = # of individuals capture in 2nd sample ___ = # of recapures in 2nd sample ___ = population size Density is the result of an interplay between processes that add individuals to a population and those that remove individuals ___________________________ is the influx of new individuals from other areas ___________________________ is the movement of individuals out of a population Patterns of Dispersion Dispersion is Within a population’s geographic range, local densities may vary greatly The __________________ pattern of a population refers to the way individuals are spaced within their area Dispersion patterns can be Clumped In a _______________ pattern individuals are grouped in __________________ Uniform In a ____________ pattern individuals are equally spaced in the environment It may be influenced by social interactions such as ___________________, the defense of a bounded space against other individuals Random In a ____________________ pattern of dispersion, the individuals in a population are spaced in an unpredictable way Demography Demography is Death rates and birth rates are of particular interest to demographers Life Tables A ____________________________ is an age-specific summary of the survival pattern of a population It is best made by following the fate of a _______________, a group of individuals of the same age The life table of Belding’s ground squirrels reveals many things about this population For example, it provides data on the proportions of males and females alive at each age Survivorship Curves A survivorship curve is The survivorship curve for Belding’s ground squirrels shows a relatively constant death rate Survivorship curves can be classified into three general types _________________________: low death rates during early and middle life, then an increase in death rates among older age groups _________________________: the death rate is constant over the organism’s life span _________________________: high death rates for the young, then a slower death rate for survivors Reproductive Rates For species with sexual reproduction, demographers often concentrate on females in a population A reproductive table, or fertility schedule, is It describes __________________________________________ of a population How do Populations Grow? Exponential Growth Exponential population growth is Under these conditions, the rate of increase is at its _________________________, denoted as rmax The equation of exponential population growth is Exponential population growth results in a ___________________________curve The J-shaped curve of exponential growth characterizes some rebounding populations For example, the elephant population in Kruger National Park, South Africa, grew exponentially after hunting was banned Does this type of growth typify what truly happens in nature? The logistical model describes how a population grows more ____________ as it nears its carrying capacity Exponential growth _____________________ be sustained for long in any population A more realistic population model _______________ growth by incorporating ____________________ Carrying capacity (K) is Carrying capacity __________________ with the abundance of ______________ _______________ The Logistical Growth Model In the logistic population growth model, the per capita rate of increase declines as ________________ is reached The logistic model starts with the exponential model and adds an expression that reduces per capita rate of increase as N approaches K The logistic model of population growth produces a sigmoid (_____________________) curve The Logistical Model and Real Populations The growth of laboratory populations of paramecia fits an ______________________ curve These organisms are grown in a constant environment lacking predators and competitors Some populations overshoot ____ before settling down to a relatively stable density Some populations fluctuate greatly and make it difficult to define______ Some populations show an Allee effect, in which individuals have a more difficult time surviving or reproducing if the population size is too small The logistic model fits few ________ populations but is useful for ____________________ possible growth Conservation biologists can use the model to estimate the critical size below which populations may become extinct What causes populations size to be regulated? Many factors that regulate population growth are ________________________________ There are two general questions about regulation of population growth What environmental factors stop a population from growing indefinitely? Why do some populations show radical fluctuations in size over time, while others remain stable? Population Change and Population Densisty In ____________________________________ populations, birth rate and death rate do not change with population density Abiotic factors may reduce population size before other limiting factors become important In ____________________________________ populations, birth rates fall and death rates rise with population density Mechanisms of Density-Dependent Population Regulation Density-dependent birth and death rates are an example of _____________________________ that regulates population growth Density-dependent birth and death rates are affected by many factors, such as Competition for ________________________ In crowded populations, increasing population density intensifies competition for resources and results in a __________________ birth rate ____________________________ _________________________ of toxic wastes can contribute to density-dependent regulation of population size _________________________ As a prey population builds up, predators may feed preferentially on that species ________________________ Factors For some populations, _______________ (physiological) factors appear to regulate population size ________________________ In many vertebrates and some invertebrates, competition for territory may limit density ___________________________ Population density can influence the health and survival of organisms In dense populations, pathogens can spread more __________________ Mechanisms of Density Independent Population Regulation Life history traits impact populations An organism’s ____________________ comprises the traits that affect its schedule of reproduction and survival The _______________ at which reproduction begins How _______________ the organism reproduces How _________________ offspring are produced during each reproductive cycle Life history traits are evolutionary outcomes reflected in the development, physiology, and behavior of an organism “Trade-offs” and Life Histories Organisms have finite resources, which may lead to ____________________between survival and reproduction For example, there is a trade-off between survival and paternal care in European kestrels Some plants produce a large number of small seeds, ensuring that at least some of them will grow and eventually reproduce Other types of plants produce a moderate number of large seeds that provide a large store of energy that will help seedlings become established __________________, or density-dependent selection, selects for life history traits that are sensitive to population density Populations ________ reproductive rate, therefore higher parental care __________________, or density-independent selection, selects for life history traits that maximize reproduction Populations have a ____________ reproductive rate The concepts of K-selection and r-selection are oversimplifications but have stimulated alternative hypotheses of life history evolution Population Dynamics The study of ___________________________ focuses on the complex interactions between biotic and abiotic factors that cause variation in population size Most populations fluctuate in numbers Some populations have “______________________________” cycles Some populations ______________________ in density with regularity Boom-and-bust cycles Why does the hare population get much higher than the lynx? The Global Human Population The human population increased relatively slowly until about 1650 and then began to grow exponentially But can earth sustain this growth rate? How does the Ecology of Community differ from that of a Population? Communities in Motion A biological community is For example, the “carrier crab” carries a sea urchin on its back for protection against predators Interspecific interactions are fundamental to community structure Relationships with other species in the community are called ____________________________________ Interspecific interactions can affect the survival and reproduction of each species, and the effects can be summarized as positive (+), negative (–), or no effect (0) __________________________ _________________________ competition (–/– interaction) occurs when species compete for a resource in short supply _________________________ competition? Which type of competition is more challanging to an individual? Ecological Niches The total of a species’ use of biotic and abiotic resources is called the species’ ____________________ An ecological niche can also be thought of as an organism’s ____________________________ What are the outcomes of interspecific competition? ______________________________________ Strong competition can lead to competitive exclusion, local elimination of a ______________________ The competitive exclusion principle states that two species competing for the same limiting resources cannot coexist in the same place ______________________________________ Resource partitioning is ______________________________________ __________________________ (+/– interaction) refers to interaction where one species, the predator, kills and eats the other, the prey Prey adapt using protective strategies _____________________________________ ____________________________ (+/– interaction) refers to an interaction in which an herbivore eats parts of a plant or alga It has led to evolution of plant mechanical and chemical defenses and adaptations by herbivores _____________________________________ Symbiosis is a relationship where Examples are ________________________________________ In ___________________ (+/– interaction), one organism, the ____________________, derives nourishment from another organism, its ________________, which is harmed in the process Endoparasite vs Ectoparasite? Many parasites have a complex life cycle involving a number of hosts Some parasites change the behavior of the host to increase their own fitness _________________________________________ Mutualistic symbiosis, or ______________________ (+/+ interaction), is an interspecific interaction that benefits both species A mutualism can be _________________, where one species cannot survive without the other _________________, where both species can survive alone _________________________________________ In commensalism (+/0 interaction), one species benefits and the other is neither harmed nor helped Commensal interactions are hard to document in nature because any close association likely affects both species __________________________________ Facilitation (/ or 0/) describes an interaction where one species can have positive effects on another species without direct and intimate contact For example, the black rush makes the soil more hospitable for other plant species by removing salt in soil Divestiy and trophic structure characterize biological communities In general, a few species in a community exert strong control on that community’s structure Two fundamental features of community structure are _______________________ and ______________________________________ Species Diversity Species diversity of a community is the ________________ of organisms that make up the community It has two components: species richness and relative abundance ________________________________ is the total number of different species in the community ________________________________ is the proportion each species represents of the total individuals in the community Two communities can have the same species richness but a different relative abundance Diversity can be compared using a diversity index __________________________________ index Diversity and Community Stability Ecologists manipulate diversity in experimental communities to study the potential benefits of diversity For example, plant diversity has been manipulated at Cedar Creek Natural History Area in Minnesota for two decades Communities with higher diversity are _______________________ productive and more stable in their productivity _______________________ able to withstand and recover from environmental stresses More resistant to ___________________________, organisms that become established outside their native range Trophic Structure ________________________________ is the feeding relationships between organisms in a community It is a key factor in community _____________________ ___________________________ link trophic levels from producers to top carnivores Food Webs A ________________________ is a branching food chain with complex trophic interactions Species with a Large Impact Certain species have a very large impact on community structure Dominant Species Dominant species are those that are most _________________ or have the highest _______________ Dominant species exert powerful control over the occurrence and distribution of other species One hypothesis suggests that dominant species are most competitive in exploiting resources Another hypothesis is that they are most successful at avoiding predators Keystone Species __________________________ exert strong control on a community by their ecological roles, or niches In contrast to dominant species, they are not necessarily abundant in a community Field studies of sea stars illustrate their role as a keystone species in intertidal communities Observation of sea otter populations and their predation shows how otters affect ocean communities Ecosystem Engineers __________________________ (or “foundation species”) cause physical changes in the environment that affect community structure What makes up an Ecosystem? Ecosystem ecology emphasizes ____________________ flow and _______________________ cycling Ecosystem Components of ecosystems Energy flow Chemical cycling Let’s first focus on Energy Flow A terrarium has the components of an ecosystem Primary production sets the energy ______________________ for ecosystems Primary production The amount of solar energy __________________________ to chemical energy Carried out by _______________________ Produces _______________________________ Amount of living organic material in an ecosystem Primary production of different ecosystems Energy supply ____________________________ the length of food chains A pyramid of production Illustrates the cumulative loss of energy transfer in a _______________________________ Chemicals are cycled between organic matter and abiotic reservoirs Ecosystems are supplied with a continual influx of ___________________________ Sun and Earth’s interior Life also depends on the _______________________________ of chemicals Organisms acquire chemicals as nutrients and lose chemicals as waste products Biogeochemical cycles Cycle chemicals between ______________________ and the _______________________ What are some examples? The _____________________ Cycle Water is essential to all organisms The _____________________ Cycle Carbon-based organic molecules are essential to all organisms The _____________________ Cycle Nitrogen is a component of amino acids, proteins, and nucleic acids The _____________________ Cycle Phosphorus is a major constituent of nucleic acids, phospholipids, and ATP What is the Biosphere? The biosphere is the Earth’s _____________________ dictates the organization of the ecosystems that make up the biosphere Earth’s climate varies by latitude and season and is changing rapidly The long-term prevailing weather conditions in an area constitute its _______________________ Four major abiotic components of climate are What controls each? Global Climate Patterns Global climate patterns are determined largely by __________________ energy and the planet’s movement in ______________________ The warming effect of the sun causes temperature variations, which drive evaporation and the circulation of air and water This causes latitudinal variations in climate Regional and Local Effects on Climate Climate is affected by seasonality, large bodies of water, and mountains The structure and distribution of terrestrial biomes are controlled by climate and disturbance __________________________ are major life zones characterized by vegetation type (terrestrial biomes) or physical environment (aquatic biomes) Climate is very important in determining why terrestrial biomes are found in certain areas Climate and Terrestrial Biomes Climate affects the ____________________________ patterns of terrestrial bones A _________________________ plots the temperature and precipitation in a region Biomes are affected not just by average temperature and precipitation, but also by the pattern of temperature and precipitation through the year Distrubance and Terrestrial Biomes ________________________ is an event such as a storm, fire, or human activity that changes a community For example, frequent fires can kill woody plants and maintain the characteristic vegetation of a savanna For example, fires and outbreaks of pests create gaps in forest that allow different species to grow Fire suppression has changed the vegetation of the Great Plains Terrestrial Biomes Terrestrial biomes can be characterized by _____________________________ Several types of ___________________________ occur in the warm, moist belt along the equator In tropical _________ forests, rainfall is relatively constant, while in tropical _________ forests precipitation is highly seasonal Temperature is high year-round (25–29C) with little seasonal variation Tropical forests are home to millions of animal species, including an estimated 5–30 million still undescribed species of insects, spiders, and other arthropods ______________________________ Equatorial and subequatorial regions ___________________________ precipitation is seasonal Temperature is warm year-round (24–29C) but more seasonally variable than the tropics Grasses and forbs make up most of the ground cover The dominant plant species are fire-adapted and tolerant of seasonal drought Common inhabitants include insects and mammals such as wildebeests, zebras, lions, and hyenas Fires set by humans may help maintain this biome ____________________________ __________________ occur in bands near 30C north and south of the Equator, and in the interior of continents Precipitation is low and highly variable, generally less than 30 cm per year Deserts may be hot or cold Desert plants are adapted for heat and desiccation tolerance, water storage, and reduced leaf surface area Common desert animals include many kinds of snakes and lizards, scorpions, ants, beetles, migratory and resident birds, and seed-eating rodents; many are nocturnal Ubanization and irrigated have reduced the natural biodiversity of some deserts _____________________________ __________________________ occurs in midlatitude coastal regions on several continents Precipitation is highly seasonal with rainy winters and dry summers Summer temperature is hot (30C+) while fall, winter, and spring The chaparral is dominated by shrubs, small trees, grasses, and herbs; many plants are adapted to fire and drought Animals include amphibians, birds and other reptiles, insects, small mammals and browsing mammals Humans have reduced chaparral areas through agriculture and urbanization _________________________________________ ___________________________________________ are found on many continents Precipitation is highly seasonal Winters are cold (often below –10C) and dry, while summers are hot (often near 30C) and wet The dominant plants, grasses and forbs, are adapted to droughts and fire Native mammals include large grazers such as bison and wild horses and small burrowers such as prairie dogs Most grasslands have been converted to farmland __________________________________________ ____________________________________________ is found at midlatitudes in the Northern Hemisphere, with smaller areas in Chile, South Africa, Australia, and New Zealand Significant amounts of precipitation fall during all seasons as rain or snow Winters average 0C, while summers are hot and humid (near 35C) Vertical layers are dominated by deciduous trees in the Northern Hemisphere and evergreen eucalyptus in Australia Mammals, birds, and insects make use of all vertical layers in the forest In the Northern Hemisphere, many mammals hibernate in the winter These forests have been heavily settled on all continents, but are recovering in places ______________________________________ The _______________________________________, or ________________, spans northern North America and Eurasia and is the largest terrestrial biome on Earth Precipitation varies; some have periodic droughts and others, especially near coasts, are wet Winters are cold and long while summers may be hot (e.g., Siberia ranges from –50C to 20C) Conifers such as pine, spruce, fir, and hemlock dominate The conical shape of conifers prevents too much snow from accumulating and breaking their branches Animals include migratory and resident birds, and large mammals such as moose, brown bears, and Siberian tigers Some forests are being logged at an alarming rate _________________________________ _________________________________ covers expansive areas of the Arctic; alpine tundra exists on high mountaintops at all latitudes Precipitation is low in arctic tundra, and higher in alpine tundra Winters are long and cold (below –30C) while summers are relatively cool (less than 10C) ____________________________, a permanently frozen layer of soil, prevents water infiltration Vegetation is herbaceous (mosses, grasses, forbs, dwarf shrubs and trees, and lichen) and supports birds, grazers, and their predators Aquatic Biomes are diverse and dynamic systems that cover most of Earth Aquatic biomes fall into two categories ________________________ Marine biomes have salt concentrations of about 3% Take up about 75% of Earth’s surface ________________________ Freshwater biomes have salt concentrations of <0.1% Freshwater biomes are closely linked to soils and the biotic components of the surrounding terrestrial biome Zonation in Aquatic Biomes Many aquatic biomes are stratified into zones or layers defined by The upper _______________ zone has sufficient light for photosynthesis while the lower ___________ zone receives little light The photic and aphotic zones combined makes up the ____________________ zone Deep in the aphotic zone lies the __________________ zone with a depth of 2,000 to 6,000 m The organic and inorganic sediment at the bottom of all aquatic zones is called the _____________ zone The communities of organisms in the benthic zone are collectively called the _________________ __________________________, dead organic matter, falls from the productive surface water and is an important source of food In oceans and most lakes, a temperature boundary called the _____________________ separates the warm upper layer from the cold deeper water Many lakes undergo a semiannual mixing of their waters called _______________ Turnover mixes oxygenated water from the surface with nutrient-rich water from the bottom Aquatic Biomes Major aquatic biomes can be characterized by their physical environment, chemical environment, geological features, photosynthetic organisms, and heterotrophs Lakes Size varies from small ponds to very large lakes Two categories of lakes _______________________________ lakes are nutrient-poor and generally oxygen-rich _______________________________ lakes are nutrient-rich and often depleted of oxygen if ice covered in winter Two additional zones associated with lakes only ____________________________ zone Primarily deep areas with small drifting animals called zooplankton graze on the phytoplankton ____________________________ zone Well lit shallow areas with rooted and floating plants Wetlands A ____________________ is a habitat that is inundated by water at least some of the time and that supports plants adapted to water-saturated soil Wetlands are among the most productive biomes on Earth Humans have destroyed up to _____% of wetlands; wetlands purify water and reduce flooding Streams and Rivers The most prominent physical characteristic of streams and rivers is ___________________ Rivers are divided into Headwaters (source of river and usually called streams) and Downstream water _________________________ are generally cold, clear, turbulent, swift, and oxygen rich; they are often narrow and rocky _____________________________________ form rivers and are generally warmer, more turbid, and more oxygenated; they are often wide, meandering, and have silty bottoms Estuaries An ________________________ is a transition area between river and sea Salinity varies with the rise and fall of the tides Estuaries are nutrient rich and highly productive Estuaries include a complex network of tidal channels, islands, natural levees, and mudflats An abundant supply of food attracts marine invertebrates, fish, waterfowl, and marine mammals Intertidal Zone An _________________________ zone is the area between the highest high tide and lowest low tide therefore, organisms are challenged by variations in temperature and salinity and by the mechanical forces of wave action Oxygen and nutrient levels are high with rocky or sandy substrate Oceanic Pelagic Biome The _________________________________is constantly mixed by wind-driven oceanic currents Oxygen levels are _____________ Turnover in temperate oceans is important This biome covers approximately 70% of Earth’s surface Phytoplankton and zooplankton are the dominant organisms in this biome Coral Reefs _______________________ are formed from the calcium carbonate skeletons of corals (cnidarians) Shallow reef-building corals lie in the photic zone in clear water about 20–30C; deep sea corals live at 200–1,500 m Corals require high ________ and a __________________ substrate for attachment Marine Benthic Zone The marine benthic zone consists of the seafloor below the surface waters of the coastal, or _________, zone and the offshore pelagic zone Organisms in the very deep benthic (abyssal) zone are adapted to continuous cold and extremely high water pressure Substrate is mainly soft sediments; some areas are rocky Shallow areas contain seaweeds and filamentous algae Deep-sea hydrothermal vents of volcanic origin on mid-oceanic ridges are surrounded by unique chemoautotrophic prokaryotes, as well as echinoderms and arthropods Neritic benthic communities include invertebrates and fishes Overfishing and dumping of waste have depleted fish populations How can the study of biology help conserve the ecosystems of the biosphere? Conservation Biology Scientists have named and described 1.8 million species and they estimate 10–200 million species exist on Earth Humans are rapidly pushing many species toward extinction ___________________________ biology, which seeks to preserve life, integrates several fields Human activities threaten Earth’s biodiversity Rates of species extinction are difficult to determine under natural conditions The high rate of species extinction is largely a result of ecosystem degradation by humans Humans are threatening Earth’s biodiversity Three Levels of Biodiversity Biodiversity has three main components _____________________________________ Genetic diversity comprises genetic variation within a population and between populations What happens to an population if there is no genetic diversity and the environment is selecting for a trait that is not in existence? _____________________________________ Species diversity is the variety of species in an ecosystem or throughout the biosphere According to the U.S. Endangered Species Act An _________________________ species is “in danger of becoming extinct throughout all or a significant portion of its range” A __________________________ species is likely to become endangered in the foreseeable future Conservation biologists are concerned about species ________________ because of alarming statistics regarding extinction and biodiversity Globally, 12% of birds, 20% of mammals, and 32% of amphibians are threatened with extinction Extinction may be local or global _____________________________________ Human activity is reducing ecosystem diversity, the variety of ecosystems in the biosphere More than 50% of wetlands in the contiguous United States have been drained and converted to other ecosystems Why is Ecosystem Diversity Important? Ecosystem Services ______________________________ encompass all the processes through which natural ecosystems and their species help sustain human life Some examples of ecosystem services Purification of air and water Detoxification and decomposition of wastes Cycling of nutrients Moderation of weather extremes Biodiversity and Human Welfare Human biophilia allows us to recognize the value of biodiversity for its own sake Species diversity brings humans practical benefits Threats to Biodiversity Most species loss can be traced to four major threats ____________________________________ Human alteration of habitat is the greatest threat to biodiversity throughout the biosphere In almost all cases, habitat fragmentation and destruction lead to loss of biodiversity For example _______________________________________ ______________________ species are those that humans move from native locations to new geographic regions Without their native predators, parasites, and pathogens, introduced species may spread rapidly Introduced species that gain a foothold in a new habitat usually disrupt their adopted community _____________________________________ Overharvesting is human harvesting of wild plants or animals at rates exceeding the ability of populations of those species to rebound Large organisms with low reproductive rates are especially vulnerable to overharvesting For example, elephant populations declined because of harvesting for ivory DNA analysis can help conservation biologists identify the source of illegally obtained animal products For example, DNA from illegally harvested ivory can be used to trace the original population of elephants to within a few hundred kilometers __________________________________________ Global change includes alterations in climate, atmospheric chemistry, and broad ecological systems Pollution of the environment compounds our impact on other species The global water cycle can transport pollutant Pollutants in a food chain can lead to _________________________________________ Nutrient pollution from fertilizer and wastes Linked to summer “dead zone” in the Gulf of Mexico Gradually thinning _________________________ layer Release of chlorofluorocarbons from aerosol cans and manufacturing Rapid warming is changing the global climate The scientific debate about global warming is over Global temperature has risen 0.8°C in the last 100 years 0.6°C of that increase occurred in the last three decades 2 to 4.5°C increases are likely by the end of the 21st century Global warming most evident in arctic Shrinking sea ice Thinning ice sheets Melting permafrost What is the proof Atmospheric CO2 did not exceed 300 ppm for 650,000 years Atmospheric CO2 is approximately 385 ppm today High levels of methane and nitrous oxide also trap heat What exactly is Global Warming? Global climate change affects biomes, ecosystems, communities, and populations Terrestrial biomes determined by temperature and rainfall Changing as a consequence of global warming Distributions of populations and species also changing Disappearance of many species being caused by changing climate Climate change affects seasonal events in some plants and animals Conservation Biology and Restoration Ecology Protecting endangered populations is one goal of conservation biology Habitat loss Population _____________________________ A harmful effect of habitat loss Splitting and isolation of portions of populations Can lead to extinctions Sustaining ecosystems and landscapes is a conservation priority Conservation biology priority Past efforts Saving individual species Today Biodiversity of ecosystems ______________________________ ecology Dynamics of a collection of ecosystems Edges can fragment ecosystems Fragmentation is corrected with ______________________________________ Protected areas are established to slow the loss of biodiversity Conservation biology focuses on _____________________________________________ Have a large number of endangered and threatened species Have a concentration of _____________________________________ Hot spot designation favors the most noticeable organisms Sustainable development is an ultimate __________________________ Biosphere is made of complex interconnections Sensible decisions needed to conserve these networks Must work for a sustainable future Sustainable development depends on continued research and application