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BIOL 1500
Marie Therese Rush

Unit 9 Biodiversity and Conservation What is Biodiversity? Biodiversity- variety within and among living organisms -from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part *“Within species” refers to the genetic diversity that can be found within a single species. -like gold- focuses on bio-prospecting, which gives impression that biodiversity is only valuable because it provides raw materials and profits for people BUT there are many other reasons why biodiversity has value Values of Biodiversity -values are inherently subjective-- may not be valued by all people -dominant species on Earth, Homo sapiens has an ethical, stewardship responsibility towards humanity's only known living companions in the universe Ecotourism- tourists visiting specific geographical sites to see natural attractions, especially animals and plants -humanity has derived many direct economic values from biodiversity, including all of its food and many of its medicines and industrial products -*plants, animals, and microorganisms help supply human beings with array of free ecosystem services, without which civilization could not persis(include such things as controlling gaseous mix of the atmosphere, generating and maintaining soils, controlling pests, and running biogeochemical cycles) -present extinction episode caused by human activity jeopardizes ethical, aesthetic, direct economic and life-support values of biodiversity; may be single most important externality associated with human economic activity Consequences of Extinction Extinction-complete loss of a species 1. Loss of Resources -loss of species cause impoverishment of wild food sources -biological resources harvested directly from natural areas include: wood (fuel, lumber), shellfish (protein), algae (gelatins), herbs (medicine) ---can cause economic harm -wild species provide unique biological chemicals (drugs, food additives, industrial products) -rosy periwinkle produces two drugs that have reduced death rate from leukemia and Hodgkin’s disease 2. Predation, Mutualism, and Competition Derailed Community- group of interacting species in the same geographic area Ecological niche- the role or ‘job’ of the species Food web- the feeding connections between and among organisms in an environment ●Mutualism-interaction between two species that provides benefits to both species -cleaner fish that remove and consume parasites from larger fish -most important to us: plants and bees (pollinator– bees transfer pollen allowing a plant to mate with another plant (bee obtains food in form of nectar and excess pollen while plant sperm is carried to female reproductive structures of another flower allowing for cross-pollination) -bees have been declining in recent years, believed to be increased level of bee Parasites- organisms that feed on other living organisms Commensalism- relationship in which one species benefits and the other is unaffected (cattle not effected by birds that feed on insects after they graze) ●Predation-act of capturing and consuming an individual of another species Predator-organism that eats other organisms ●Competition- interaction between species when both require the same resources within a habitat -generally reduces size of competing populations (test-remove one species from environment and if other species increases than two species are competitors) Competitive exclusion- process of establishing harmless organisms in ecosystem that reduce levels or harmful organisms Keystone species- species that has unusually strong effect on the structure of the community it inhabits 3. Disrupted Energy and Chemical Flows Ecosystem- all of the organisms and natural features in a given area -function described in terms of the rate at which energy flows through it and the rate at which nutrients are recycled within it Energy Flow -nearly all ecosystems primary energy source is sun -producers convert sun energy into biomass during process of photosynthesis -amount of sunlight reaching the surface of Earth and the availability of water at any given location are major determiners of both trophic pyramid structure and energy flow through it -research indicates decline in diversity, even without decline in habitat, may lead to loss energy being made available to organisms higher on the food chain, including people who depend on wild-caught food Nutrient Cycling-process that relies on a healthy community of decomposers in the soil and which makes nutrients available to plants -when essential mineral nutrients for plant growth pass through food web they are generally not lost from the environment -nitrogen is major component of protein and abundant protein is essential for proper growth and functioning of all living organisms -nitrogen is often nutrient that places an upper limit on production in most ecosystems- more nitrogen generally leads to greater production, while areas with less available nitrogen can support fewer plants (and therefore animals) 4. Psychological Effects -some argue diversity of living organisms sustains humans by satisfying deep psychological need Biophillia-humans innate desire to be surrounded by natural landscapes (Edward Wilson) -people seek natural landscapes because our distant ancestors evolved in similar landscapes (inherited genetic imprint of pre-agricultural past) -no evidence of a gene for biophilia but there is evidence that our experience with nature has psychological effects -studies in dental clinics indicate patients viewing landscapes have decreased blood pressure, in hospitals patients who could see trees recovered quicker and with less pain that those who viewed brick walls Why Biodiversity Doesn’t (yet) Pay -in developing countries, the economic pressures are so high, people use whatever they can find today to survive until tomorrow. As long as that's the case, there will be no support for biodiversity at all -unless it can be made more profitable to leave a forests standing or a wetland wet than it is to convert the land to farm, pasture or parking lot Biodiversity up Close -University of Guelph is home to the Biodiversity Institute of Ontario -Ontario Biodiversity Council is group of 22 people who represent industry, government, environmental and conservation groups, aboriginals, and academia, and whose mandate is to implement, evaluate, and promote the Ontario Biodiversity Strategy, first published in 2005 -in 2010 they published a report “The State of Ontario’s Biodiversity 2010” which used 29 indicators to determine the health of biodiversity in Ontario -29 indicators were grouped into 3 categories: pressures on Ontario’s biodiversity, state of Ontario’s biodiversity, and conservation and sustainable use -each indicator was rated in terms of trend (i.e., improvement, deterioration, no change, mixed, baseline, and undetermined) and data confidence (i.e., high, medium, low, and N/A) (ie.one indicator under pressures on Ontario’s biodiversity looked at climate change and the condition and survival of Polar bears; the trend was rated as deteriorating, and the confidence in the data was high) -in June, 2011, the Ontario Biodiversity Council published a report called “Ontario’s Biodiversity Strategy, 2011: Renewing Our Commitment to Protecting What Sustains Us.” -identified three main goals and 15 targets that they hope to achieve by 2015 and 2020 Biological Classification How Many Species Exist? Biological classification- field of science attempting to organize biodiversity into discrete, logical categories -astounding variety of life on the planet, so much that it is difficult to determine exact number of species -counting species is challenging because scientists argue over the definition of “species” differences exist in the way specimens are stored and catalogued, and searching all the publications and museums in the world is difficult in order to determine if a “new” species was already discovered by someone else -important to identify all the different species because every organism, including ourselves, is interconnected in the web of life(if we know what is out there, we can learn about it and protect it and by doing so, preserve own existence) Evolutionary classification-system of organizing biodiversity according to the evolutionary relationships among living organisms Phylogeny- evolutionary history of a group of organisms Kingdoms and Domains Domains- modern species divided into three large groups: Bacteria, Archaea, Eukarya -most identified living organisms are in domain Eukarya Kingdom- the most inclusive group of organisms (in other words, classification systems, the level below domain on the hierarchy) Classification Systems -no one system of classification works perfectly (some creatures don’t fit nicely into any one group) -many years, biologists used a system with five kingdoms (plants, animals, fungi, protists, monera) -now many have switched to using six categories: four kingdoms (plants, animals, fungi, protists) and two domains (bacteria and archaea) because it better reflects evolutionary relationships The Diversity of Life Origin of the Domain Eukarya Eukaryotes-third domain of life that contains all of the organisms that keep their genetic material within a nucleus inside their cells -likely developed from prokaryotes that produced excess cell membrane that folded into the cell itself Endosymbiotic theory- mitochondria and chloroplasts found in eukaryotic cells appear to have descended from bacteria that took up residence inside larger primitive eukaryotes -when organisms live together, the relationship is known as symbiosis Prokaryotes- don’t have nucleus which provides a membrane-bound, separate compartment for the DNA in other cells, lack other internal structures (both bacteria and archaea) -most are unicellular-each cell is an individual organism -often called microbes/microorganisms- hundreds of times smaller than cells that make up our bodies Microbiologists- scientists who study microscopic organisms, especially referring to those who study prokaryotes Bacteria-extremely small (microscopic), single-celled, with no cell nucleus -best known for causing diseases, but they are found everywhere and most are harmless or helpful -example is E. coli, a type of bacteria that lives in your intestin(Most types are harmless, but some can make you sick and cause diarrhea) Archaea-extremely small (microscopic), single-celled, with no cell nucleus -look like a bacteria, but their genetic makeup is very different -best known for living in extreme environments (super hot, super salty, or environments without oxygen) Kingdom Protista Protists-unlike bacteria and archaea, have a membrane around their cell nucleus -usually found almost anywhere there is moisture, soil, leaf litter, ponds, oceans, etc - range from single-celled organisms to huge colonies of single cells joined together, to large multi-cellular organisms -some are animal-like, some are fungus-like, and some are plant-like -many can move using structures called flagella or cilia -what makes protists different from plants or animals is how their cells function internally. -example Plasmodium, a single-celled parasite that causes malaria -Unwanted green algae like that growing in a fish tank or bird bath are also protists, as are the large multi- cellular seaweeds. Protista-made up of the simplest known eukaryotes -most protists are single celled creatures although have enormous multicellular (many celled) forms -contains organisms resembling animals, fungi, and plans (most remain unknown) Phyla- groups just below level of kingdom -no agreement on how many are contained within Protista (some as low as 8 while others 80) Algae- only members of this kingdom with ability to manufacture food (via photosynthesis) -photosynthetic protists Animal-like protists: -cilliates- free-living single-celled organisms that use hair-like structures to move -flagellates-use one or more long whip-like tail for locomotion – most are free living, but some cause disease by infecting human organs -amoebas- flexible cells that can take any shape and move by extending pseudopodia (false feet) Fungus-like protists: -slime molds- feed on dead and decaying material by growing net-like bodies over a surface or by moving about as a single amoeba-like cells Plant-like protists: -diatoms- single cells encased in a silica (glass) shell -brown algae-large multicellular seaweeds -green algae- closest relatives to l
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