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Mid Term Study Guide

by: Jennifer Pacicco

Mid Term Study Guide Biology 1006

Jennifer Pacicco
GPA 3.74
Ecology and the Evolution of Organisms
Tara Scully

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Ecology and the Evolution of Organisms
Tara Scully
Study Guide
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Popular in Ecology and the Evolution of Organisms

Popular in Biological Sciences

This 26 page Study Guide was uploaded by Jennifer Pacicco on Thursday February 26, 2015. The Study Guide belongs to Biology 1006 at George Washington University taught by Tara Scully in Winter2015. Since its upload, it has received 158 views. For similar materials see Ecology and the Evolution of Organisms in Biological Sciences at George Washington University.


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Date Created: 02/26/15
Biology Mid Term Study Guide Misconceptions about Science 1 People think that science is a collection of facts a Science is a search for explanations about the natural world b Science is Fluid c Scientists rely on 3 pillars Order Explain Achieve 2 Scientists are always right and unbiased a Scientists are human b Limited by current technology 3 Science is a collection of hard facts that don t change a Everything is tentative b Experiments show or quotindicatequot or suggest c Again limited by technology 4 Scientists always know what they are talking about a Hypothesis a tentative explanation for an observation phenomenon or scienti c problem that can be tested by further investigation b Theory a set of statements or principles devised to explain a group of facts or phenomena especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena The Scienti c Method Hypothesis can be tested 0 Through observational studies Descriptive a statistical study to identify patterns or trends in a situation but not the casual linkages among its different elements Analytical a comparative study designed to reach casual inferences about hypothesized relationships between risk factors and outcomes 0 Use statistics to estimate the reliability of data Correlation a relationship or connection between two things based on co occurrence or pattern of change Causation Correlation does not imply causation Through experimental studies 0 Experimental Treatment Group Independent variable Dependent variable 0 Control Group 0 Limits to the Scienti c Method 0 Useful for studying the natural world 0 Scienti c analysis cannot 0 Make moral judgments Although information leading to those judgments may be based on scienti c information o Prove or disprove faith based beleifs 0 Determine personal aesthetic values Characteristics of life 0 Cellular and Utilize DNA Reproduce Develop and Grow Capture Storage and Use of Energy 0 Maintain Internal Conditions 0 Sense and respond 0 Evolve 0 Individual organisms change rapidly Growth of individual A seed becomes a tree 0 Groups of organisms change slowly Species Group of interbreeding organisms Produce fertile offspring Evolution 0 Characteristics of a species changing over time Biological Hierarchy Cell 0 Tissue Organ Organ System 0 Individual organism Population 0 Community Ecosystem Importance of Biological Hierarchy From the ground up 0 Intricate interactions that affect us all 0 Understanding the hierarchy helps us to understand the interactions 0 These interactions have implications in medical research technology environmental issues and the future of our species History of Classi cation Linnaean Classi cation 0 A rank based system of taxonomy Grouping based solely on physical characteristics 0 18th century by Swedish naturalist Carolus Linnaeus before Darwin s theory of evolution 0 Scienti c name genus species Capitalize rst name but not second ltalicize both names Systematics o Produces evolutionary trees 0 Relatedness based upon common ancestry o Formalized in 19605 by Willi Hennig Systematists 0 Map out the Tree of Life 0 From life s common universal ancestor to all the groups that exist today 0 Understand how organisms evolve Modern Classi cation 0 Family Tree 0 Individual relationships Evolutionary tree 0 Relatedness of groups of organisms o Called Cladogram a branching treelike diagram in which the endpoints of the branches represent individual species of organisms Phylogeny the evolutionary development and history of a species or trait of a species or of a higher taxonomic grouping of organisms Constructing Evolutionary Trees 0 What do the parts of the tree represent 0 Taxon taxa group being studied normally species Tips of tree 0 Node a point of divergence between groups Branching points of tree Independent evolution 0 Lineage descendants of a common ancestor Branches or any line rom node to next node or to tip Continued evolution Shared derived features 0 Characters heritable traits that can be compared acorss organisms Shared because the character is common to at least two Hneages Derived because the character evolved in the lineage leading up to a clade the character de nes that clade Clade a grouping that includes a common ancestor and all of its descendants living and extinct Clades form a quotnested hierarchyquot Three Domains Bacteria Archaea Eurkaya Six Kingdom Bacteria Archaea Protista Plantae Fungi Animalia No living organisms is any quotmore evolvedquot than any other living organism Predict the Evolution of Organisms Evolutionary trees 0 Are hypotheses of evolution 0 Based on shared derives features DNA physical characteristics and or biochemical characteristics 0 Can be used to help make predictions of where groups t in and relationships 0 Prediction of characteristics and behaviors of related organisms 0 Useful for humans 0 Prediction of Parental Care 0 A behavior characteristic may be predicted based on the evolutionary tree Challenges to classic taxonomy Organisms that are related don t appear to be related The Unity and the Diversity of Life 0 Problems facing systematists o Similarity in structure Convergent features 0 Not from common ancestory o Evolved independently Example opposable thumb 0 Difference in structure Vestigial features Vestige of ancestry o Extinction Removes species and can thus remove living evidence of evolutionary relatedness Need to look at fossils Preserved remains or impressions o organisms 0 DNA data Sequence comparison Able to compare groups that have little apparent physical similarities Limitations too much data 0 Non living things Virus 0 Like living organisms 0 Contain DNA 0 Reproduce o Evolve Classi ed by 0 The type of genetic material they contain 0 Their shape and structure 0 The type of organism they infect o The disease they produce Viruses are host speci c 0 Lack characteristics of life 0 Not made of cells Just genetic material not always DNA and protein 0 Lack homeostasis energy collection reproduction response and energy coHchon Depend on cells to do these funcUons 0 Attack organisms in every kingdom of life Evolution Background 0 Important prelude for Darwin 0 Change is evident in the layers of soil Evolution is the best explanation for the fossil record Current diversity of life shows the age of the earth Line of descent that leads to modern species 000 o Adaptation to the environment is a primary product of evolution 0 What was wrong wasn t explained yet 0 Structures used get bigger better those that aren t deteriorate 0 Acquired characteristics are past down to offspring Biological Evolution 0 Charles Darwin Descent with modi cation 0 By natural selection Core Concepts of evolution 0 All life is linked through a common ancestor o Populations of living things change with time o The environment in uences this change 0 So that advantageous traits are selected over less advantageous traits Natural Selection 0 How does it work 0 Inference 1 struggle to survive few do 0 Inference 2 heritable traits give better reproductive and survival success 0 Inference 3 population change over time The Evidence for Evolution 0 Six lines of evidence 0 FossHs o Traces of evolutionary history Homologous Of or referring to a characteristic shared by twp groups of organism because of their descent from a common ancestor Vestigial organs are reduced or degenerate parts whose function is no longer needed Convergent evolution characteristics that result from convergent evolution are said to be analogous Convergent evolution in similar adaptions These are considered analogous structures 0 Similarities and divergences in DNA 0 Direct observations of genetic change in populations Arti cial selection is the process by which only individuals with certain inherited characteristics are allowed to breed Ex farming crops domesticated animals 0 Continental drift Portions of the supercontinent Pangaea began to drift apart about 200 million years ago 0 The present day formation of new species Macroevolution Rapid evolutionary change due to environmental conditions Harsh conditions drive changes in the population 0 Changes can be seen in our time Main players of life Bacteria and Archaea o Prokaryotes o Divergence Archaea posses genes and metabolic pathways more similar to eukaryotes Archaea use a much greater variety of energy sources that eukaryotes and include quotextremophilequot species 0 Pathogens No known Archaea pathogens Bacteria can be pathogens 0 How do prokaryotes evolve 0 Sex exchange of genetic information o Conjugation connection and exchange between living bacteria 0 Transformation DNA taken up environment Can produce pathogenic strains and antibiotic resistant strains 0 Transduction Exchange of DNA through infection by phages virsues Microevolution and Macroevolution 0 From the beginning 0 Universal common ancestor What does evolution explain 0 Formation of groups Change in genetic characteristics in a population over time Why does evolution have to relate to a population level and not an individual 0 What is changing 0 Proportion and presence of characteristics within a population Characteristics genetic information 0 Key terms Allele version Genotype combo of version is an individual 0 Genetic Basis of Evolution 0 Version alleles o Genotype characteristic Dark Light 0 What is changing 0 Ways to measure change Version Allele Frequency Combination of versions Genotype frequency 0 What causes genetic changes Mutation Recombination Gamete production 0 Fertilization Four Mechanisms for Evolution 0 Evolution causes changes in allele frequencies in 4 waysquot Mutations Random events 0 All variation comes form mutations genetic recombination Can be harmful bene cial or neutral Gene ow Exchanges alleles between two different populations random 0 New alleles being introduced 0 Alleles being removed Genetic drift Chance events leading to differences between organisms in reproduction or survival 0 Random 0 Not based upon any characteristics of individuals 0 Due to Environment Reproduction Establishing new population 0 Potential outcome 0 Bottleneck effect 0 May reduce genetic variation Fixation neutral harmful or bene cial Environmental disturbances 0 Hurricanes o Volcanic eruptions o Clearing land for development 0 Overhunting a species Reproductive chance events include o Gamete production 0 Fertilization Leads to random changes in allele frequencies Smaller population greater the effects Founder effect when a few individuals establish new population Natural selection When individuals with favorable traits have a higher reproductive rate Three types 0 Directional selection Mode of natural selection in which an extreme phenotype is favored over other phenotypes causing the allele frequency to shift over time in the direction of that phenotype o Stabilizing selection Genetic diversity decreases and the population mean stabilizes on a particular trait value 0 Disruptive selection Extreme values for a trait are favored over intermediate values The variance of the trait increases and the population is divided into two distinct groups How Evolution Works 0 Mutations gene ow and genetic drift change allele frequencies at randomly 0 Natural selection is the only means by which a population become more adapted to its environment Macroevolution Speciation 0 Different selective pressures cause population to become different 0 Reproductive isolation prevents gene ow between populations 0 A secondary consequence of the evolution of populations Pre zygotic barriers Ecological barrier 0 Habitat 0 Temporal o Behavioral isolation Mechanical isolation Gametic lsolation Post zygotic barriers Zygotic death 0 Most hybrid offspring do not survive Hybrid performance 0 Hybrid is infertile 0 Hybrid breakdown 0 When does speciation occur Due to geographical isolation o Allopatric speciation 0 Geographical separation prevents two or more populations of a species from mating 0 Evolution occurs in both populations Reproductive barrier When reintroduced they no longer mate Without geographical isolation Sympatric speciation o Hybrids 0 Rapid change in chromosome number polyploidy Sexual selection 0 A form of natural selection 0 Sexual dimorphism 0 Females place selective pressure on males Peacock s feathers Lion s mane 0 Evolution Does Not Craft Perfect Organisms o What constraints exist Survival and reproductive trade offs Genetic Developmental 0 Natural extinction is the result of a specie s inability to adapt to adverse changes in the environment o How does evolution work 0 Microevolution Small scale changes 0 How much variation exists now compared to the past 0 What is causing this variation 0 Macroevolution Large scale changes new species o Is the variation that has occurred changed the population so that they can no longer mater with the original population 0 How can mating be prevented De ning species 0 The morphological species concept Separate and distinct group of organisms by rhe unique set of morphological characteristics 0 The biological species concept Group of populations that can interbreed with one another but are reproductively isolated from other such groups 0 Limitations 0 Morphological 0 Biological Outcome of evolution 0 Adaptation Match maker between populations and their environment Relate to complex characteristics Important functions Unexpected Outcomes 0 Multi drug resistant pathogens Overuse of antibiotics Not taking an entire prescription of antibiotics Agricultural industrial use Overuse of other substances Coevolution 0 Interaction between two species strongly in uences their survivial so that they evolve in tandem 0 Why do diseases often become less severe over time o Ecological Economical Problem any change in DNA sequence II T I I migration of individuals which changes the genetic variation of the population different habitats or timing of mating displaylacts which attract a mate physical structures don39t fit random events that kill off individuals or egg and sperm physically don t fit I I I I I allowr certain individual to breed differential survival and reproduction of individuals with favorable traits History of Life Humans are Animals Chordates Mammals Primates Hominids Evidence from the past FossHs o Preserved remains or impressions of individual organisms that lived in the past and are often found in sedimentary rock 0 Mass extinctions o Periods of time during which great numbers of species went extinct throughout most of Earth 0 Adaptive radiation 0 When a group of organisms expands To take on new ecological roles To form new species 0 How Reduction in competition New adaptation that enables it to use its environment in new ways 0 Where do we come from o Nocturnal tree dwelling mammals o Hominid Evolution 0 Primates evolved 80 65 mya 0 First hominids appeared 57 mya 0 Characteristics of hominids Large brains Bipedal walking upright Toolmaking Early Hominids Partially Opposable Big Toes 0 Early Hominids walked upright Big toe was partially opposable Modern humans have no opposable toe Origin and Spread of Humans 0 Ancient H sapiens showed primitive technology 0 H Sapiens gave rise to Neandertals and modern humans 0 Out of Africa hypothesis 0 Argues that every living human being is descended from a small group in Africa who then dispersed into the wider world displacing earlier forms such as Neanderthal Multi regional hypothesis 0 The human species rst arose around 2 million years ago and subsequent human evolution has been within a sinlg continuous human species Abiotic Factors The Biological Hierarchy displays the levels of non living 0 Important abiotic factors 0 Conditions of the environment Temperature Light Water Wind Weather and climate Global patters of abiotic conditions 0 The Sun 0 Radiation of heat Energy of movement Temperature 0 Ozone Filters radiation Keeps in heat 0 Electromagnetic Radiation Visible light UVIight Heat 0 Atmospheric gases Absorb heat radiating from Earth s surface 0 Carbon dioxide 0 Water Vapor Nitrous oxide Methane 0 Temperature changes as you ascend into the atmosphere Elevation 0 Light and Locations 0 Angle of incoming light relative to global position Visible light UV light Heat 0 Timing is everything Day vs night rotation 24 hrs Changes in seasons tilt and location of the earth around its orbit of the sun 365 days June solstice Northern Hemisphere tilts toward sun March equinox equator faces sun directly December solstice Northern Hemisphere tilts away from sun 0 Earth Wind and Water 0 Air exposed to sun will warm at the surface 0 0 More sun more heat more expansion Where does it go Hot air rises and moves toward poles because more hot air coming Cold air falls More sun more heat more expansion Hot air can hold water lnto atmosphere cool down fall back Cold air releases water Giant convection cells Four stable and two variable 0 Two polar Two tropical Two in between Solar radiation plus rotation of the earth Prevailing winds All stable convection cells have easterly winds Variable cells have westerly winds Water goes to the air Evaporation O Transpiration Why 0 Heat 0 Wind Water goes to the surface Precipitation Why Convection cell air moving into atmosphere Elevate me O Mountains Elevation Windward side 0 Difference in temperature 0 Promotes precipitation Leeward side 0 Air moves from cold to warm 0 No moisture Rain Shadow 0 What else about water 0 O O Oceans and large lakes Water absorbs releases heat slowly Moderates temperature in surrounding landmasses Ocean currents in uenced by Rotation of Earth Differences in water temperatures Poles and tropics Directions of prevailing winds Gravitational pull of both sun and moon In uence regional climates 0 Weather or climate 0 0 Current state We look for trends to allow for predictability Difference base upon Solar energy wind precipitation ecology geology atmoshper Tropical regions 25 times more gtWarmth gtMoisture gtWind predictability gtStability in climate More warmth moisture and sunlight increased productivity Biomass Biodiversity More producers and consumers 0 Weather patterns La Nina cooler air and water El Nino warm air and water Understanding the ecological impact Ecology o Interactions of environment and organisms o Necessary to study impact of interactions 0 Examples Introduced species zebra mussels Economic cost Damage to biosphere chloro uorocarbons Health and organism damage 0 Human Impact 0 Introduced species zebra mussels 0 Economic cost 120 billion 0 Introduced toxin CFCs 0 Economic cost Unknown 0 Interactions with the Environment 0 Web of interconnected relationships Biomes Land Biomes o Tundra Boreal forest temperate deciduous forest Grassland Chaparral Desert Tropical forest Aquatic Biomes o Terrestrial biomes Land topography Nutrients from terrestrial biomes 0 Climate Temperature rainfall and wind Seasonal changes and major El Nino 0 Physical characteristics Salt concentration depth movement Populations and Communities What is a population 0 Group of interacting individuals of a single species in a speci c area 0 Population size 0 Population density 0 How do ecologists put a number on a population size OO 0 Census taking counting everyone Mark and recapture Different times of day seasons Sample mark and resample area of organism Quadrats Subset of area that the population lives in Usually a circle or square Transects Lines that bisect the area of interest Individuals counted along the line Challenges in counting 0 000000 Migratory organisms Flying organisms Microscopic small organisms Organisms with hard to reach habitats Rare organisms Organisms with different forms through their lifetime How is a geographic area habitat de ned to delineate one population from the next Changes in Population Size 0 Change in size over time Increasing Birth rate time period 0 Immigration Decreasing Death rate time period 0 Emigration o Dependent on environmental factors Patterns of Population Growth 0 J shaped in exponential growth Increase by a constant rate Doubling time o S shaped in population with limits 0 Populations growth with limits Carrying capacity Irregular uctuations Population cycles 0 Food Shortage irregular Growth Not all populations show an S or curve over time Limiting factors can have a huge impact Population Cycles 0 Predator prey relationships demonstrate population cycles Growth Limiting Factors Density independent 0 Factors that are not related to the size of the population Weather uctuations Fire and oods Pesticide use 0 Factors that are related to the size of the population in the area Food shortages Lack of habitat Disease Predators Community Biodiversity 0 Species diversity species richness and relative abundance 0 Geographic diversity distribution of a community across a geographic range 0 Genetic diversity variation of genes within populations Symbiosis o Often mistaken as always being bene cial 0 Interaction Two or more organisms Live in on or around one another Very close association at some point in their lifecycle o Mutualism Both species Increasing the survival and reproduction of both of the interacting species Gut inhabitant Seed dispersal Pollinator Behavioral o protection Evolution of mutualism occurs when bene ts outweigh the costs Effects of Community 0 Distribution geographic diversity Abundance species diversity 0 Indirect effects 0 Commensalism 0 Where one species bene ts at no cost to the other 0 Exploitation Where one species bene ts other is harmed Exploiters are generally consumers falling into 3 main categories Herbivores eat plants or plant parts 0 Predators kill other animals prey for food 0 Parasites live in or on the organisms they eat Outcomes Induced defenses spines on cacti 0 Warning coloration poison dart frog Camou age o Mimicry o Batesian mimicry one species copies the form of another to gain superior protective capability o Mullerian mimicry several species that have protection against predators come to resemble one another Behavioral adaptation May ater behaviors of prey Parasitic relationships 0 A parasite lives on or in a host from which obtains nourishment 0 Internal parasites include nematodes and tapeworms 0 External parasites include mosquitoes and ticks Pathogens are disease causing parasites o Pathogens can be bacteria viruses fungi or protists Many parasites cause behaviors in host organisms that bene t the parasite Introduced species sometimes disrupt the ecological communities there 0 Consumers can restrict distribution of food source 0 Competition I Where both species are harmed Niche Sum tota abiotic and biotic needs of a species population to survive and reproduce Both species cannot be as successful as they would in the others absence Two main types o Interference competition 0 Direct exclusion 0 Competition between two species affects the distributions of those species 0 Exploitative competition 0 Both have the same needed resource Outcomes Limits distribution and abundance of species that share resources or space 0 Either o Localized extinction competitive exclusion o Coexistence sharing of a habitat o Niche partitioning adapt to use niche in different ways therefore reduces competition 0 Competition and Coevolution Competition can increase the differences between species Character displacement Species evolve to become different over time 0 Results of Species Interactions Coevolution is the independent evolution of two or more species Process of building replacing communities 0 Trophic composition 0 Food web 0 Contain many food chains Producers Consumers 0 Primary 0 Secondary o Tertiary The base of trophic recycling decomposers 0 Transfer of Energy 0 How much of the Sun s energy is harvested by the living world 0 How much of the collected energy makes it through each successive trophic level 0 Too much energy required to support quaternary consumers 0 These top predators rely on the stability of the other populations int the community 0 Where do humans t in Most energy lost as metabolic heat Keystone Species Have a tremendous effect on a community 0 If removed entire community can change 0 May or may not be a predator Building replacing communities 0 Communities change over time 0 Process is called succession When succession ceases mature community is result 0 Primary succession o Colonizing a new habitat Secondary succession 0 Communities recover from disturbance As climate changes so do communities 0 Recovery from human caused disturbances 0 Clear cutting o Pollution o Eutrophication Humans can cause long term damage to communities 0 Clear cutting and re Ecosystems and Global Impact Ecosystems Productivity 0 Nutrient cycles Global Change 0 Transformation Changing Earth s chemistry Alternation of ecosystems by pollution Invasion of non native species Nutrients can be recycled Energy ow is a one way street 0 Sun gt producers gt consumers gt decomposers Net Primary Productivity 0 Rate of energy capture 0 Amount of energy captured minus metabolism and heat loss 0 Biomass added 0 What are limiting factors of NPP o Sunlight 0 Water 0 Nutrient recycling 0 Temperature Rate of Energy Capture Varies o NPP amounts vary across globe Exception deserts Variations upwelling Coral reefs sunlight shallow Freshwater systems 0 Highly in uenced by runoff from terrestrial systems 0 Rivers and marine habits will distribute estuaries with lots of nutrients The Most Productive Ecosystems Tropical rainforests coral reefs estuaries wetlands farmlands Secondary productivity is the rate of new biomass production by consumers o Decomposers responsible for breaking down most primary and secondary productivity Ecosystems Productivity 0 Nutrient cycles 0 Carbon Cycle Released by food web via respiration or humans Oceans contain largest stores of carbon Carbon in atmosphere is only 004 Fossil fuels and sedimentary rocks represented argest reservoir 0 Nitrogen Cycles Atmosphere contains largest stores of nitrogen 78 Nitrogen is limited in rock and aquatic systems Mutualistic symbiosis between nitrogen xing prokaryotes with some plants 0 Sulfur Cycle Sea spray Bacteria Volcanic eruptions or humans Atmosphere contains sulfur Sulfur is found in rock sediments 0 Water Cycle Evaporation Transpiration Extraction ecosystems Global warming affected by water vapor Largest store of fresh water ice caps Most water is salt water 0 Phosphorus cycle Phosphorous leaches from rock into terrestrial and aquatic systems Humans extract from rock 0 Nutrient Biogeochemical cycles 0 Transfer of nutrients between organisms and the physical environment Food chains web Reservoirs Exchange pools 0 Two kinds of nutrients cycles Atmospheric Sedimentary o Nutrients from abiotic to biotic o Nutrients limited to no access to organism 0 Exchange pool readily available to organisms Atmospheric Cycles 0 Cycles between terrestrial and aquatic ecosystems to atmosphere 0 Four major atmospheric cycles 0 Global Change 0 Worldwide change in the ecosystems o What are some clues that global change is happening Transformation Changing Earth s chemistry Alteration of ecosystems by pollution Invasion of non native species 0 Land Transformation Physical and biotic changes to land surface Destruction of natural habitat for resources 0 Agriculture 0 Urban growth 0 Water Transformation Physical and biotic changes to water 0 People use more than half of world s fresh water Alter water cycles 0 Altered ow of nearly 70 of world s rivers Over 50 population lives within 3 miles of the coast 0 Evidence of Transformation Aerial photos Satellite data Urban boundaries 0 Impact of Transformation Destruction of whole ecosystems NPP Destruction of needed resources Health and economic issues 0 Changes in Earth s Chemistry Bioaccumulation Persistent organic pollutants POP 0 Long lived o Harmful effects 0 Polychlorinated biphenyls and dioxins Biomagni cation Bioaccumulated chemical 0 Increase at successively higher trophic legels o Resistant to degradation in the body Pesticides Chloro uorocarbons CFCs Endocrine disrupters o Alteration of ecosystems Carbon Humans drill and extract fossil fuels that are burned releasing carbon dioxide 75 Reduction of plants throughout the world for varirs reasons 25 Biotic Impact in response to C02 0 Initial impact lncrease photosynthesis and water use 0 Long term impact Few species can maintain growth others drop to lower growth 0 End result loss of biodiversity Effect on ecosystem 0 Changing one population affects many others in community Abiotic impact 0 Climate change Greenhouse gases Absorb heat radiating from Earth s surface Cause global warming Nitrogen Industrial nitrogen xation 0 Removed nitrogen from atmosphere making it available Combustion from factories adds nitrogen to atmosphere Eutrophication o Leads to dead zones Biotic impact o Terrestrial and aquatic communities Productivityincreases Number of species decreases o Abiotic impact 0 Vegetation reduces nutrient runoff Sulfur Sulfur dioxide released during burning of fossil fuels 0 Has an international impact Increases acid rain reduces plant life Water 0 Reduction of freshwater stories in glaciers and ice caps Computer simulations 0 Increase in ocean surface temperature 0 Increase in severe weather 0 Reduced quality of water 0 Recued availability of water Invasive Species Introduced species become invasive The estimate damage from invasive species worldwide totals more than 14 trillion What do ecologist measure 0 Abiotic global factors Temperature Moisture Wind Sunlight Message location proximity to terrestrial aquatic formations atmosphere tilt rotation o Populations Number of individuals Range of population Density Population growth patterns 0 Density dependent factors 0 Density independent factors 0 Message population size doesn t remains table 0 Communities Biodiversity Species number relative abundance 0 Geographic space 0 Genetic variation across the community 0 Message more diversity more stability and productivity All the species interactions Mutualism Commensalism Exploitation Competition 0 Message each species will have multiple types of interactions within their community Movement of nutrients energy Producers Consumers Decomposers 0 Message each species contributes to the web like interactions of nutrient energy movemtn through a community


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