Final Exam Notes! (2/2)
Final Exam Notes! (2/2) BISC 1006
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Date Created: 03/21/16
Reproductive Factors in Evolution Thursday, February 18, 2016 Pre & Post Zygotic Barriers Pre Z (before egg implant/formation) 1. Ecological = diff habitats 2. Temporal = reproduce @ diff times 3. Behavioral = mating specific 4. Mechanical = reproductive structures don't match! 5. Gametic = sperm/egg don’t match! Post Z (after formation, this keeps eggs from growing into healthy offspring) 1. Zygotic death = DNA of 2 species don't match >> genetic failure 2. Hybrid performance o Stop the formation of a zygote! o Bc of "hybrid breakdown" aka over time, offspring become infertile Clicker Q: For evolution to occur, gene flow has to stop! That makes 2 populations different over time! They're isolated (cockblocked) so they can't have kids >> evolving Pace of Evolution How fast or slow does evolution happen? What speeds it up/affects it? o When gene flow breaks down over time, that leads > evolution! o Geographic barriers separate 2 populations of the same species! >> subspecies >> 2 distinct species Speciation = how do species evolve? Allopatric Speciation = aka geographic barriers o Islands have lots of biodiversity! o^lots of environmental variation so there ain't a lot of competition oResult = "ring species" Develop when populations loop around a geographic barrier ^ populations at the two ends of the loop are in contact with each other, yet individuals from these populations cannot interbreed. oEX - Darwin's birds Over time, they became v different distinct species bc they had access to a ton of resources & food Sympatric speciation = individuals w/in a given population become so different over time that they're considered a new species Reproductively isolated! Lake Victoria Cichlids - from 2 species of cichlids, 500!! were made Ecological isolation (cockblocked) & sexual selection (pretty ones were chosen to m8) Apple Maggot Flies - used to live on trees, then food source dwindled & mating time changed Polyploidy = when the number of chromosomes in an organism's cell doubles! o This means it can't mate with orgs of less chromosomes! o Plants increase the amount of DNA to solve the zygotic death problem! o ^and so they can make a fertile kid plant Pace of Evolution (RATE THEORIES) Gradualism Small changes accumulate over long periods of time >> in large changes Punctuated Equilibrium extinction events (Ice ages, Cambrian explosion) REALITY = it's a lil bit of both! More gradualism tho What causes variation over time? Micro (small) >> Macro (big) MICROEVOLUTION Gene flow Genetic drift Mutation Natural selection Migration of Completely rando! Change in the Helps the population individuals btw Lead to DNA sequence become better fit to the populations >>differences in environment Needs to be stopped survivability & Only beneficial kind of for macro evolution to reproduction evolution! happen! MACROEVOLUTION All the little changes add up! They make a new species over time Reproductive isolation is caused by Pre Zygotic barriers (before egg implant/formation) 1. Ecological = diff habitats 2. Temporal = reproduce @ diff times 3. Behavioral = mating specific 4. Mechanical = reproductive structures don't match! 5. Gametic = sperm/egg don’t match! OUTCOMES of evolution No matter wha, adaptations always happen The environment is constantly changing so species need to change too! If they don't change/evolve, they die off (natural selection!) Big Picture = Global Diversity & Weather Tuesday, February 23, 2016 Topics - how orgs are distributed & what affects macro/microevolution in populations (abiotic factors!) also, what is weather? Hierarchy of LIFE (big > small) Biosphere | Biome | Ecosystem | Community | Population | Organism CLICKER QUESTION Weather = temperature patterns over short periods of time Climate = weather over long periods of time! Abiotic Factors Not living! o Temperature o Light wind o Weather o Climate Tells us where orgs are distributed Sun: big guy! dictates weather, moisture, wind! o Energy of movement = how molecules move (micro) affect the bigger things (macro!) Measured by Fahrenheit o Electromagnetic radiation Heat - it's getting hot in here, so take off ozone molecules.. Visible light on the spectrum lets organisms who use PHOTOSYNTHISIS make fooddd UV light - v harmful! Can damage ur DNA o Ozone Upper atmosphere layer found in the stratosphere :) Filters out harmful UV rays and excess heat! :( Greenhouse gases (CO2, methane etc) trap in heat! This causes global warming yall ^ Weather CLICKER Q = (C) Elevation. Abiotic factors like this dictate what can survive where! LOCATION LOCATION!! vvvv important to temperature patterns The higher you are, the colder you are! It's warm @ sea level bc the ground absorbs the heat yall Poles - in either direction, it gets colder o That's why it's warmest @ the equator! LIGHT Weather is determined by the TILT of the EARTH As the earth is MORE/LESS exposed to the sun, it's summer v winter SEASONS are determined by proximity Come again? MO sun MO heat MO expansion! o Hot air can hold water, which explains why rainforests are @ the equator o More sun exposure means more evaporation! MO precipitation >> greater diversity o Rainforests are @ the equator are home to lots of diff species o WHY? When heat hits cold air, the water it's holding gets released as rain (precipitation) Giant convection cells = patterns of air movement hold moisture and move into the atmosphere til it reaches cold air >> precipitation >> drops back to earth to restart the cycle! v consistent @ poles + the equator! See arrows below… Circulation of air/moisture >> poles! There's 6 on earth (we live in the variable middle ones!) Ours don't follow the same pattern, they use reversals We don’t have consistent sun exposure ^that's why we have varying weather! Smh How to predict the weather (according to Raven Baxter) https://heidyfd.files.wordpress.com/2012/09/tumblr_ldzy0widze1qfccvpo1_500.gif Solar Rotation = as the earth rotates, the wind bends differently Easterlies + Westerlies are the winds Easterlies = winds coming from the east >> west o @ the equator o V consistent weather patterns o We look @ these to see what the weather will be like ^Hurricanes that hit DC start in the tropics, then get hit by Westerlie winds! West >> east WAHTA Water goes to the air o Evaporation - when we're exposed to more sun, it dries up the atmosphere o Transpiration - we lose a lot of water from plants. The tropical rainforest contributes to the available water we get from the atmosphere o HIGH wind increases evap + transpiration! Rain shadows! Mountains force air to move upward! ^ simulates a convection cell (precipitation @ one side) ^ coastal ranges makes a diff biome! Ex: you get rain on one side and dry desert conditions on the other (Sierra Nevada) Frank Oceans & Large lakes Water near land masses helps keep temps moderate o During the day, water absorbs the heat o @ night, it gets cold by the water bc it's released o Europe = v different climates bc of the Gulf Stream! Brings heat >> Europe That makes temps lower Ocean currents = influenced by o Wind o Rotation of Earth o Diffs in water temp o Gravitational pull of the Sun + Moon Weather patterns Hard to predict bc there's a lot of variables oSolar energy oWind oRain oSnow In the DMV area, the Shenandoah Mtns block snow & shiz - > Tropics are v stable/constant so we look @ those (x2 the moisture & sun exposure as us) Westerlies aren't v constant bc convection cells are NOT ISOLATED Weather men (meteorologists) look @ pacific ocean - classify em as either La nina Cooler air Cooler water El nino Warmer air Warmer water ^those flow a certain way depending on air/water temp But Why Tho Ecology is imp bc our lives are impacted o Food! o Economy! o Space! Human impact smh o Dumping = cargo ships bringing stuff over brought zebra mussels too! Nasty lil things clog our shi We destroy/break down the Ozone Layer Just one molecule of Chlorofluorocarbon CFC (in hairspray) destroys 100,000 !!! of the ozone Ozone protects us from UV rays which cause cancer! Controls how much heat gets in!! (why it's hot af & global warming is a thing) We are fam - interconnected relationships o Dingoes, kangaroos + sheep population problems o ^they ate a ton of plants and ^incr the competition o WHAT'S THE BIG IDEA? We need to take relationships btw orgs into mind when we screw em up and play god (breeding, eliminating some animals) Biomes Terrestrial Aquatic o Water & temp determine where o Nutrients from terrestrial biomes, orgs will live! climate & human activity determine MO water HI temp global distribution/biodiversity! MO producers/energy MO Phosphorus biodiversity! Nitrogen o Less life can be supported in etc Deserts o Temperate climates Limiting resource = nutrient availability ^bc they don't have water/warm They rely on runoff to provide weather! nutrients to producers! ^fewer producers live here Salt water dictates what kind of orgs Producers are @ the base of da can live in oceans! The most productive places are close food chain to land! ^bc the good ish drops to the bottom Population Evolution Thursday, February 25, 2016 5:14 PM Ecologists count populations! o It's hard to put a # on migrating organisms tho o We human ^ affect migration patterns o Flying organisms hard to count too ("bruh did I count that one? Damn idk") o Microscopic orgs are too damn small to keep track of! o Isolated orgs are hard to reach (live in the ice caps for ex, deep sea diving) o Rare orgs o Transitioning - some look different over the span of their life! CLICKER Q - What type of growth is the global human population experiencing currently? a. Logistic growth b. Density independent growth c. Irregular growth d. Exponential growth e. Regression growth Increases by Decreases by Birth rate = Death rate = #/time period #/time period o Immigration o Emigration Population ecologists look at these ^ over time! Who's dyin? How fast are they dying? Humans destroy habitats!>> reduced population 3 Patterns! 1. J-shaped in exponential growth o This is happenin rn! o When you increase the # of orgs by a constant r8 o Start out slow, then blimp up, then level off! o WHY - lots/unlimited resources ayee 2. S-shaped in populations with limits o When there's limited resources, can only support a certain # of individuals @ a certain time o ^ "carrying capacity" = the max amount of ppl the environment can sustain o Balance of birth/death rates o WHY - resources availability changes over time competitors are eating your shi nutrients in runoff screws up/adds more food! 3. Irregular fluctuations o Most common! o Bc of a change in environment over time! o Population cycles = Relationship btw predator / prey over time Controlled by food source!! Rando - density independent (not related to size of pop!) Fire/floods Natural disasters Wipe out individuals idgaf about how many there are! Not rando - density dependent (size related!) It's all about access to food/home/resources Food shortages Lack of habitat Disease Predators CLICKER Q = If population size remains 200 after day 12, what is true about the birth and death rate? 1. both increase 2. both decrease 3. birth increases and death decreases 4. death increases and birth decreases 5. they are equal Community Ecology All the individuals of all species in a given area + their interactions! o Can be small or large scale! Ecologists are interested in o What’s the scale? (bacteria in your gut vs all the bacteria in the whole forest!) o How diverse are the species? (biodiversity) Biodiversity! o imp so we know how stable + productive a community is! o Species d= richness & relative abundance o Geographic d= there's diff versions around town o Genetic d= more variation means you can react to environment changes betta o ***not just a number!! o ***relative abundance - MO species = MO stable!! Interactions! Win-win for both species! Gut bacteria helps you kill off microbes! ^ they get a nice lil meal too! ^win - win Ex - Timon (meerkat) picks out nits, Mutualism Pumba (warthog) gives him a ride! (++) Both get help surviving & reproducing Gut inhabitant Seed dispersal Pollinator Behavioral Protection One guy benefits, other guy isn't bothered Commensalism (+ 0) Barnacles on whales These are consumers! o Obvi one species (the one getting eaten) is harmed o The other guy gets a meal! Herbivores - plant eaters Exploitation (+ -) Predators - kill animals for food Parasites - live in/on host to feed! o Exploitation Outcomes: prey/host are pressured to evolve! If they don't develop strategies to deal, they'll die off! Competition (- -) Both species are harmed! Fight for access to resources (food, habitat etc) "I'd be better off if you were dead" Population Ecology cont'd Tuesday, March 1, 2016 RECAP - All life is related from a common ancestor! Bacteria looks a lot like the universal common ancestor 3 domains (bacteria, archaea, eukarya) 6 kingdoms (bacteria, archaea, eukarya, protista, plantae, fungi, animalia) Microevolution >>> macroevolution! Micro - gives new features When diffs vary by a lot, reproductive isolation happens & you get macroevolution! Macro - new groups forming (new lineages) Every node below represents macro! Growth limiting factors What influences population growth patterns? o Density! - being densely packed in keeps you from growing! o Food shortages - if you don't have access it limits how many ppls get fed! o The right kinda habitat - not everyone can fit into the ideal crib o Disease o Predators Not related to size o Weather fluctuations o Fire & floods o Pesticide use Community Interactions Trophic composition = energy, food + nutrient passage Succession = replacement of communities over time! Interaction types! Good for both species! Ex - Timon (meerkat) picks out nits, Pumba (warthog) gives him a ride! Both get help surviving & reproducing Gut inhabitant Seed dispersal Pollinator Behavioral Mutualism Protection V important in establishing ecosystems! (++) Coral reefs support the diversity of life yall w/o mutualism, the community would be bland af One guy benefits, other guy isn't bothered Commensalism (+ Barnacles on whales 0) These are consumers! o Obvi one species (the one getting eaten) is harmed o The other guy gets a meal! Herbivores - plant eaters Predators - kill animals for food Parasites - live in/on host to feed! o Coevolution happens o Pathogens - type of parasite that causes disease! o Mosquitoes are parasites but aren't always pathogens (disease causing) o Parasites are adaptive af! They can move from host > host (dog > human etc) o ^some can change your behavior! Dogs become not afraid of cats Humans get more risky lol Exploitation (+ -) o Exploitation Outcomes: prey/host are pressured to evolve! If they don't develop strategies to deal, they'll die off! o Ways they deal - Warning coloration poisons predators! Induced defenses (cacti have spiky spines! Venus fly traps) Camouflage - hides you from predators! Avoid getting eaten Batesian Mimicry - prey evolved warning coloration to look like a harmful one! Irl they aint shi but predators think they are so they'll leave em alone Mullerian Mimicry - 100% of the time, the coloration is real. 2 species resemble each other, both species benefit yall! Strength in numbers - a flock of prey stick together to fight off predators! #squad Competition (- -) BothFight for access to resources (food, habitat etc) Biodiversity ! Species diversity = relative # of 1 species compared to another o High relative abundance tells you - more stable & productive! Geographic diversity = how well distributed the community is across a region Genetic diversity = variation of genes in a pop o V important to reproductive r8s ACROSS ALL 3 (greater diversity = greater productivity!) Population & Comm Ecology Thursday, March 3, 2016 CLICKER - farmers use A. Artificial Selection! Community Biodiversity Species diversity - how many species are in a particular comm! o Relative abundance: the # of one species compared to another o ^ there are "relatively" more ants on earth than humans Only stable if you're genetically diverse too!! Geographic diversity o How diffs are seen over a region o Can be broad or narrow Diverse communities are MORE PRODUCTIVE! (+ stable bruh) Mutualism - win win! TYPES 1. Gut inhabitants - microbes in your bod help you! 2. Seed dispersal - helps create diverse comms for producers around the globe! i. Fruit evolved bc it attracts animals to spread their seeds around! Bc sweet :) ii. ^ even if you eat the seed, it'll pass thru your bod and poop it out to get planted somewhere loll iii. ^imp bc parent doesn't COMPETE w/ child for nutrients! 3. Pollinator…coevolution - orgs rely on plants n vice versa for genetic diversity! i. Buddies rely on one another! ii. ^yucca plants ex = both need to survive or they'll go extinct! iii. ^we go down together 4. Behavioral…orgs have behaviors that help one another! i. Shrimp gives goby fish shelter "bruh stay @ my place" ii. Goby fish warn the shrimp about danger "hey dude look out!" 5. Protection… i. Finding nemo - Anemone & clown fish protect each other! ii. The clownfish wiggle dance so the anemone can breathe better (more circulation) iii. Anemone are a cool af house for fish iv. ^^win-win! Exploitation - + / - (one benefits, other is hurt) Types 1 - Herbivores (eat plant) 2 - Predators (eat meat) 3 - Parasites (live in/on the orgs they eat) OUTCOME New species sometimes disrupt ecological processes Competition Niche bit - if someone else can do your job betta, you dead (extinct!) Interference Resource (habitat) is directly excluded from the other One species "wins" and uses energy to exclude the other org "want" High v low tide Low is where the party's @! ^but there's only enough for one guy, so they compete for space Interfere w/ access to it! They don't need it to survive tho Can survive in a high tide area Exploitative Both need the same resource Limits how much is available to the other "need" EX- citrus wasps outcompeted the native species! ^the OG wasps went extinct OUTCOMES - so wha? Limits distribution of resources! You can have o Localized extinction = competitive exclusion Result of "want" competitive interference! o Coexistence = sharing a resource or habitat! Result of "need" competitive exploitation! Coevolution - when 2 species become more different over time! >> character displacement Character displacement - when competition forces em to physically change appearance Beak size ex: over time, beak sizes changed to fit the seeds they're competing to eat! ^ stabilizing selection! If they didn't change, localized extinction would happen :( Niche partitioning = adapting to a new role w/in the community bc some new b^%& can do your job better (this reduces competition!) oHow?? They use a diff abiotic resource! EX - barnacles on whales - had interfering competition "want" ENERGY https://www.youtube.com/watch?v=7LnBvuzjpr4 What're Trophic Levels? Follow energy from one level to the next ^ how does it change from producers v consumers v decomposers etc? Interactions affect how much is lost from 1 level to the next!! ^ if you don't have enough lower level orgs, you can't feed higher level carnivores etc! oThe bottom tier producers are the basis for our trophic sys! Food web oProducers oConsumers Primary Secondary Tertiary Quartenary (needy af! If the lower levels aint well stocked, they die) Energy Transferrr All of our energy comes from the sun! Yo but like - how much of the sun's energy do we harvest? o We only use 2% of solar (sun) energy o Some is lost to heat! ^ and how much of that energy makes it thru the trophic levels? o U lose 90%!! Each level! o By the time you get to bigger consumers aka predators (tertiary/quartenary) you lose a ton of energy! o ^ that's why those species are rare af o ^ they need the bottom levels to be stable in order to survive (& have stuff to eat) WHAT ABOUT US? o Humans lose most energy from metabolic heat! Corn (127 cals) - used for processing shi, ethanol etc Beef patty (127 cals) - has a diff distribution of energy! o The cow is fed corn, so there's more inside it even though they're the same # of cals! o ^needs to be transported, processed etc Keystone Species "Keystone" - help increase the biodiversity! V important to the community! If they get removed, the ENTIRE comm changes! o HUMANS are keystone bc we add & kill off species o May or may not be a predator o Plants: fig trees o Herbivores: snow geese and elephants o Starfish: if you remove em, mussel populations plummet! Building n Replacing Communities Communities change over time bc of abiotic factors! o Diff nutrients are available Process is called succession When succession stops >> mature community o There aint a comm that has lasted forever bc abiotic factors are always changing Primary succession - new consumers taking over the habitats of smaller orgs (replace em!) o Volcanic islands o Glacier retreat: as grass grows, there's more nutrients + bigger orgs can come in and feed on em! REPLACE the OG Sand dunes Secondary succession - a disturbance (like natural disasters) causes the community to recover w new orgs! o @ first the area is deserted, then new guys roll in to inhabit o EX - Yellowstone after a fire Climate change >>> community change!! Recovery o Humans dirty af! We pollute, destroy forests etc This behavior affects the communities of orgs o GOOD NEWS - we can recover from it & reverse the damage :) Community Ecology Tuesday, March 8, 2016 5:16 PM CLICKER = What is menhaden? v important fish to the Chesapeake! Overfishing depletes the # and screws up the system 3rd biggest source of fish food in the WORLD! oImpact = burns off energy when transported > Louisiana to get processed! Spans from Canada >> gulf of Mexico Chesapeake Bay Largest estuary in North 'Merica (mix of fresh + salt water) TROUBLE IN PARADISE o 1/2 the forest shoreline is gone! o ^ to make space to grow corn, wheat, soy! Most of those crops are fed to animals in feedlots smh The runoff from that ^ herbicide ish leaks into the bae o Underwater grasses + 98% of oysters are GONE! If you like crabs, listen up ^ crabs nest here to lay eggs o Wetlands = most productive part of estuaries! Ecosystems + Global Change Ecosystems = the community + abiotic factors! Energy movement Nutrient movement Pollutants Invasive species Energy How do we get energy into our trophic system? o The sun! (solar energy) solar is converted > chemical energy= primary productivity o ^it's converted so all organisms can use it! o ^the sun is cool n all but we need the chem energy o "Biomass" is how we measure how productive they are! o "Rate limiting factors" big talk for what keeps it from getting shi done! The "rate" is how productive they are Sunlight *Temperature *Moisture Nutrients *most important ones!! Nutrients got flow "energy" and "nutrients" are V DIFFERENT o Nutrients can be recycled & stored! o Energy is transferred so we can use it! Energy moves in one way: in n out! Solar > chemical > lost to heat energy! sun producers consumers decomposers ^decomposers are most efficient! Bc they harness more energy than basic b consumers NPP (net primary productivity) o Aquatic ecosystems are v productive to spread nutrients! Deposited as sediments - nutrients end up at the bottom like when you add hot cocoa mix to water and it falls to the bottom Most nutrients are @ shorelines, close to land! o Terrestrial ecosystems are v productive, absorb sunlight! Most imp factors are temperature + moisture! ^ that's where they thrive! Worst @ poles bc it's cold & dryish Best @ the equator bc it's moist + warm! Secondary Productivity ^what consumers produce! How consumers convert what they eat >> biomass On avg, you lose 90% of gained energy each trophic level! Nutrients movin Btw orgs and the environment! They can be moved via = o Food chain/web o Reservoirs (locked away from orgs. You can’t tap into em!) o Exchange pools (available to erybody. You get nutrients! Everybody gets a nutrient!) Nutrient cycles Sedimentary Atmospheric o Carbon (found as CO2) o Phosphorus! Atmospheric cycle! Nutrient stuff stored in rock When we tap into reservoirs (aka fossil Us humans extract what we need from fuels) we're releasing more CO2 in the rock >> into fertilizers atmosphere!! Producers out compete others o Nitrogen (most common gas in the ^doing this and adding too many atmostphere!) nutrients f's up the oxygen supply (EUTROPHICATION) Nitro fixation = extracting more from the atmosphere ^ in algae, ^bacteria, "dead zones" (low oxygen) so bigger orgs can't survive! Industrial nitrogen fixation = extracting even more Nitro smh o Bc of eutrophication, we f up NPP o Sulfur (SO2) f^%$ w/ it >> acid rain! Low biodiversity Acid rain = destroys water Low production ecosystems boii Unstable!! When you burn fossil fuels, air quality is ass (Europe gets affected too bc Westerlie winds!) o Water pollution + melting ice caps means we f up our fresh water sources! Eutrophication Process where we add nutrients to water! (via soil runoff) Soil has a ton of carbon in it Too much carbon >> eutrophication >> algae blooms >> dead zones Aral Sea Basin (extreme example of human impact) Water affects how hot/cold it is! (climate) Cycle = o Evaporation > transpiration > precipitation AS Basin is in the Middle East Source of fresh water for Afghanistan, Uzbekistan etc! NOW it's dried up to a desert!daaaaamn o Changed climate! o ^v hot days, v cold nights like a desert o Increases need for water! Pollution Bioaccumulation (things that go into your bod + don't leave!) o POPs (persistent organic pollutants) Harmful af Resemble stuff we already know PCBs & dioxins smh (they look like what we produce naturally!) o They bioaccumulate + biomagnify (nasty lil stick around!) o Bioaccumulate = go into your system and DON'T LEAVE o Biomagnify = when the POPs are resistant to breaking down + move up the trophic system over time! WHYY - constantly getting exposed to it WTF - if we eat the producers who ate pests, we eat the pest too! You can't just wash off the shi Pesticides (DDT) o Bye bye birdy o bad news for bird populations CFCs o Damages ozone! The "Plastics" aka Endocrine disrupters ^stuff that affects your hormones WHY TF DO THEY ADD CANCER CAUSING SHI TO MY TUPPERWARE?? o BPA is an ingredient inside to keep plastics shatterproof + clear Plastic bottles/canned food/baby bottles have endo disrupters that leech into yo food! BPA & phthalates make you hit puberty earlier! BPC is the new kid on the block (even worse for you!) If this arrow sign looks familiar it don't mean "recycle" The higher the #, the higher risk for cancer! Invasive Species When introduced species become invasive, they impact food availability Don't have predators or parasites Damaging af! To the economy + ecosystems Food Production! Trophic systems & Community ecology Thursday, March 10, 2016 Herbicides (Impact!) Conversion of grassland >> farmland => Dust Bowl! o Smh before they touched it, the grass was v productive o ^after it converted, it turned into a desert! o ^happened bc they destroyed the nutrients When you mess with the base of a trophic system, all levels are pressured to evolve! o The NPP (Net Productive Product) goes downn Insecticides (Impact!) Kills off primary + secondary consumers ^some native consumers die bc no more food! Native species >> invasive so no consumers left! Pressures existing community to evolve! Fertilizers Good for certain producers, bad for others! Bad for native crops who have to compete w/ new kids! They can become invasive Community impact = No more niche partitioning! o There's more exploitative competition (one species will go extinct!) o ^the producers get lucked out :( o Rate limiting stuff = Nitrogen Evolution impact = fertilizers are tryna keep one species growing o ^favors LESS biodiversity! You only want 1 type of plant to grow o ^there's MORE genetically weak species Animal Food Production Antibiotics Farms use a WHOPPING 90% of ALL antibiotics!! o Bc they're injected w/ so much, they poop it out! o ^that poop gets into runoff o ^runoff leeches into water (aquatic system) o ^we drink polluted water so we become >> antibiotic resistant & genes f'ed up! Irrigation - culmination of issues! Used to make crops grow ^excess in land (terrestrial) leeches into the water (aquatic) Climate change o Less water >> less moderation of temperature (DESERT) Ecosys interactions = how does shit get from land > water? o Manure + nutrient runoff brings all 4 rate limiting stuff into the aquatic system! Nitrogen, phosphorus & sulfur o Combination Effect! (nutrient runoff) As animals poop, the concentrated nutrients, fertilizers + manure hit water Shit hit the wall! MO nitrogen MO algae! >> dead zones! >> eutrophication! o Algae are all "this is my house" and keep any other producers from surviving o ^they suffocate em so nothing can live (dead zones) o Eutrophication = big organisms can't be supported in dead zones
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