Examples - What is Ecology? What is Ecology? Systematics Taxonomy. Microbiology. Ecology and Evolution. Physiology. Developmental Biology.

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1 Wht is Ecology? The study of the interctions between orgnisms nd their environment. Orgnism plnt, niml, microbe Environment biotic Non-living components soil, wter, nutrients Biotic Interctions with other orgnisms competition, predtion, symbiosis Exmples - Wht is Ecology? Physiology Systemtics Txonomy Ecology nd Evolution Genetics Microbiology Developmentl Biology Orgniztionl levels in Ecology Orgnisml Popultion Community Ecosystem Questions t different Orgniztionl levels in Ecology Orgnisml How individuls re ffected by their biotic nd biotic environments. Popultion Trends nd fluctutions in bundnce or density relted to biotic or biotic environment. Community How do interctions mong species determine distribution nd bundnce of popultions in prticulr re or hbitt. Ecosystem How do ptterns of energy, mss nd nutrients flow through ecosystems. 1

2 Ecology s science Ecology is science so wht is science? Science systemtic methodology to develop predictive models bout the nturl world. Seeks to explin nturl phenomen Pose, develop nd test hypotheses Does not prove nything, refines models tht mke predictions bout the nturl world Properties of hypotheses Must be flsifible Must be testble Must mke prediction bout some nturl phenomenon Is neither proven or disproven. Observtions (results of experiments) either support or do not support hypothesis Theory vs. Theory Common lnguge use of theory conjecture, opinion or specultion E.g. politicl pundit hs theory bout who will win the presidentil election in November 2008 Scientific use of theory well tested nd supported model describing nturl phenomenon E.g. scientist, using the theory of grvity, cn plot the position nd speed of the erth in November 2008 theory is formed from hypotheses tht re repetedly tested nd supported. theory is the highest level of scientific understnding 2

3 n Ecologicl Theory Popultions will compete for limited resources. Turn this into hypothesis Environmentlism Environmentlism is not science politicl movement or world view Does not mke predictions, test hypotheses Seeks to protect nd conserve nturl environments Belief tht humns hve morl obligtion to do no hrm Not to be confused with the science of conservtion biology ( subdiscipline within ecology) The ecologicl study of rre nd endngered species. History of the Environmentl Movement Erly 1900 s extinction of pssenger pigeon, ner extinction of bufflo motivted Woodrow Wilson to form the US Ntionl Prk System First ntionl prks- Yellowstone nd Yosemite 1949 ldo Leopold Snd County lmnc Humns hve morl responsibility to not hrm the environment Rchel Crson Silent Spring, book tht sprked US environmentl movement. Dngers of pesticide use (DDT) Modern environmentl groups Greenpece, Sierr Club 1973 Endngered Species ct Ecology nd Environmentlism blurred lines Thoms Mlthus (1798) 1 st to hve concerns bout humn popultion sizes nd sustinbility 1 st popultion biologist by extension 3

4 Summry Ecology is science Conservtion biology is science Environmentl biology is not science Ecologists or conservtion biologists re scientists nd my lso be environmentlists The most importnt theory in biology Theory of evolution Simply sttes tht the genetic composition of popultions chnges over time. n exmple - Environmentlists re not scientists, but my lso be ecologists or conservtion biologists Nturl Selection One mechnism for evolution Requires the following be true Popultions re vrible Vritions re heritble Vritions ffect individuls bility to cquire resources Resources re limited, individuls compete, nd those who re best t getting resources reproduce the most -> re most fit These re ll hypotheses, we should be ble to design experiments to test their predictions. Environmentl Protection gency Strted in December 1970 Mjor inititives Energy str progrm Cr fuel economy rtings Bn of DDT Clen ir ct Wter qulity monitoring Regultion of hzrdous wste disposl Recent chnge crbon dioxide 4

5 Fitness in the Environment In nturl selection, ll tht mtters is how mny offspring you produce. Fitness is not defined by survivl Fitness is defined by number of offspring produced Exmple Two birds, Bob nd Tom, live in very hrsh environment Bob survives for 5 yers, reproduces in three yers nd produces 6 young Tom only survives two yers, reproduces once, but produces 8 young in one yer Modern Exmple Drought on islnd reduced seed bundnce Bird bundnce drops with seed bundnce Birds with lrger beks cn utilize wider vriety of seeds Bek size is heritble Men bek size chnged during drought 5

6 dptive Rdition Rpid evolution of group stemming from single common ncestor Specition Hbitt Hbitt B Specition Hbitt Specition Hbitt fvors phenotype Coloniztion Hbitt B Hbitt B fvors phenotype 6

7 Specition Hbitt fvors phenotype Misconceptions bout nturl selection nd evolution Is not rndom process Hbitt B fvors phenotype Isoltion + different selection pressures -> divergence Does not led to better species, it is nondirectionl Cn result in very rpid chnges, s fst s the environment cn chnge Nturl Selection nd Ecology Ecology is the study of the interctions between orgnisms nd their environment (biotic nd biotic) Nturl selection describes process through which popultions compete for limited resources Thus, the sciences of ecology nd evolution re very tightly linked. History of Life on Erth Erth formed ~5-6 by Not hospitble for life for 1-2 billion yers Physiology Systemtics Txonomy Microbiology Ecology nd Evolution Developmentl Biology Genetics First fossilized life 3.8 by (3,800,000,000) 7

8 biotic Synthesis Erly Erth tmosphere No O2 H 2 O H 2 NH 4 CH 4 High energy Formed simple mino cids mino cids joined to form the first self replicting proteins Stnley Miller nd Hrold Urey (1953) biotic Synthesis biotic synthesis hs nothing to do with Evolution First fossilized life by Microbil mts Erly life didn t fossilize well Oxygention of tmosphere Evolution of photosynthesis ~3.5by Use energy of sun to form crbohydrtes Oxygen ccumultes in tmosphere tmosphere trnsformed from reducing to oxidizing Use of oxygen to fuel metbolism = dptive rdition 8

9 History of Life long with oxygen, erth becomes more stble nd livble Ozone (O 3 ) lyer develops Fewer steroids Less volcnic ctivity Until my when Erth freezes Snowbll Erth 10 million yers, frozen Simple life under ice ner equtor survived Volcnic ctivity relese CO 2, nothing to bsorb it, globl wrming melts ice 9