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Ecology The scientific study of the distribution and abundance of organisms and the interactions that determine distribu

Ecology The scientific study of the distribution and abundance of organisms and the interactions that determine distribution and abundance Begon , Harper, Townsend, 2006, Ecology, Blackwell.

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Ecology The scientific study of the distribution and abundance of organisms and the interactions that determine distribu

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  1. Ecology The scientific study of the distribution and abundance of organisms and the interactions that determine distribution and abundance Begon, Harper, Townsend, 2006, Ecology, Blackwell

  2. Ecology is the scientific study of the distribution and abundance of organisms and the interactions that determine distribution and abundance • Lecture outline • The evolution of life and life histories • The flux of energy and matter • Individuals and populations • Ecological communities • Positive and negative species interactions • Trophic networks • Distributions in time • Distributions in space • Function and diversity • The human impact

  3. Literature

  4. Literature

  5. Ecologicalslideshows http://www.slideshare.net/marglema9/ecology-1 Ecological e-books http://www.ebooksdownloadfree.com/download/ecology-1.html

  6. The scientific study of the distribution and abundance of organisms and the interactions that determine distribution and abundance The scientific method Deduction Top down logic Theory Theory Hypothesis modification HypothesesTestable predictions HypothesesTestable predictions Observa-tions Hypothesis testing Observa-tions Induction Bottom up logic A theory is used as a testable set of logically coherent hypotheses Hypothesis are assumed of being falsifiable The core of a theory is difficult to falsify because it can always be modified in a way to match empirical observations

  7. In the natural sciences we often do not test theories. We treat theories as an expectation under predefined conditions and are interest in the deviation of reality from expectation. Theory Observations Modify the theory to match observations Modify theory The core of any theory is hard to falsify. It is impossible to veryfy the core. Difference too large Difference (Residual) Conditions of the theory not met The new hypotheses do not directly follow from our theory. They contain an empirical element. In this case the theory becomes untestable and therefore unfalsifiable. Hypotheses, testable predictions

  8. Theory predicts the number of insect species to rise to the power of 5/4 with plant species richness We use c2 or Kolmogoroff Smirnoff tests to infer whether the theory matches the data. Often these formal tests will reject the theory. Residual Gaston 1992 We do not test the theory. We use the theory and the empirical data to study additional factors. We calculate the residuals and regress them with the area under study. We detect four areas with much too low and one area with too high species richness of insects.

  9. Whatisecology? The term ecology was coined 1866 by Ernst Haeckel in his habilitation lecture. Oikos: home Ecology deals with patterns and with processes in the living world. Aims of ecology: Describing the place of living beings in their environment Explaining abundances, distributions, and interactions of living beings Predicting the changes in the abundance and distribution of living beings Controling changes in the abundance and distribution of living beings Ernst Haeckel(1834-1919) The basic units of ecological research are Genes IndividualsPopulationsSpecies Autecology deals with the life history of single species Population ecology deals with the abundance and distribution of a group of interbreeding organisms Community ecology deals with a group of interacting species Evolutionary ecology deals with the evolutionary history of todays ecological systems

  10. The scientificstudy of the distribution and abundance of organisms and the interactionsthatdeterminedistribution and abundance Distribution and abundancemightrelate to genes, individuals, populations, orspecies The manifold of genesorspeciesiscalleddiversity. Applied to alllivingbeings we speak of biodiversity Charles Robert Darwin (1809-1882) Alfred Russel Wallace (1823-1913) Number of marinefamilies

  11. Allopatric , peripatric, and sympatric speciation Allopatric speciation is generally slow Species home range Spatial breeding barrier Peripatric speciation might be fast Time Allopatric and peripatric speciation: New species emerge by genetic divergence in geographically isolated regions Sympatric speciation: New species emerge within the same habitat by any other breeding barrier. The include behavioural, resource use, or morphological barriers.

  12. The diversification of species Tinamou SouthAmercia / Africa Ostrich Tinamou Rhea New Zealand Spotted Kiwi Great Kiwi North Island Kiwi Rhea South Island Kiwi Australia Cassowary Emu 80 Time 0 Cassowary Lowdiversityof ninespecies Comparably high geneticdiversity Today’sbiodiversityislargelycaused by evolutionaryhistory and platetectonics

  13. Zosterops poliogaster Zosterops abyssinicus

  14. Postglacial colonization of Europe During the last 10,000 years Central and Northern Europe was recolonised from multiple glacvial refuges where species survived the ice age. The refuges are centres of gentic diversification. Major refuges where: The Maghreb Spain Turkey SicilyCyrpus Crete We reconstruct colonisation routs by the analysis of genetic diversity across Europe. Because colonising populations are often small they are generically impoverished(founder effect). Hewitt G.M. 1999. Postglacial recolonisation of European biota. Biol. J. Linn. Soc. 68: 87-112.

  15. Postglacialcolonization of Europe Carabusauronitens Colonisation gradient Foundereffects Orderedgeneticloss Popu-lations Relictpopulations Vicariant(scattered) geneticloss Colonisation gradient The allele - sitesmatrixissortedaccording to allele richness

  16. Postglacial colonisation of European Tenebrionidae (Coleoptera) Reconstruction of postglacial colonisation using phylogenetic relatedness of species Three major colonisation routes Three major postglacial refuges with high numbers of endemics and high rates of glacial speciation

  17. Past and present fragmentation Distribution of South American rainforest refugia (100,000 to 20,000 BP) based on the overlap of postulated refugia for birds, butterflies and plants. Shading represents probability of locations being refugial. Whitmore, T.C. ,Prance, G.T. 187. Biogeography and Quaternary History in Tropical America. Blackwell.

  18. Convergent evolution by similar selective pressures

  19. Ecological niches Charles Elton, 1900-1991 Joseph Grinnell, 1877-1939 G Evelyn Hutchinson, 1903-1991 The niche is an n-dimensional hypervolume, where the dimensions are environmental conditions and the resources that define the requirements of an individual or a species to practise The niche is the sum of the habitat requirements that allow a species to persist and produce offspring. The niche is the role a species plays in a community, rather than a habitat. Profession Place Two niche dimensions of a plant Performance of a species Suboptimum Light Performance Optimum Condition Repro-duction Growth Water Survival A given habitat filters species according to the abiotic conditions

  20. Specialist species Generalist species Performance Condition Ecological niches emerge from differences in performance along the gradient of habitat conditions Formally a niche is the place of a species within a multidimensional hypervolume spanned by all resources used by this species. Generalist species have relatively broad niches in comparison to specialist species. A habitat is the place where a species occurs. Do not mismatch habitat and niche! Fundamental niche Performance Realized niche Condition

  21. The carbon isotope ratio of body tissues (13C ⁄ 12C = δ13C) depends on resource width, while the nitrogen isotope ratio (15N ⁄ 14N = δ15N) increases in insects with trophic level. Ground beetles (Carabidae) on Mazurian lake islands top Trophic position Error bars denote a standard error basal Zalewski et al. 2013, Ann.Zool.Fenn Number of resources Parts of the species are well segregated in trophic niche space, while another part of species highly overlaps in resource use. The plot shows also three different guilds of species with similar resourse use.

  22. The basic resources of life Energystorage Proton source Carbon source Organiccompounds Energystorage Electronacceptor Energy Facultative store of energy excess Light (CH2O)n (CH2)nH2 Heterotroph Organotroph Phototroph CA+ D--H+  +E + S → (CH2O)n + DA + ES Reduction Oxidation Chemotroph Lithotroph Autotroph Chemical reaction Water, Hydrocompounds Organic compounds Waste CO2 Green plants, Cyanobacteria 6CO2 + 6H2O + light + ADP → C6H12O6 + 6O2+ ATP C6H12O6 + C6H12O6 + O2 + ADP → (CH2O)n + CO2 + H2O + ATP Animals, fungi Nitrosomonas bacteria CO2 + NH3 + O2 + ADP → (CH2O)n + HNO2 + H2O ATP

  23. Resources and feeding types Purple non-sulfur bacteria Cyanobacteria, green plants Firmicutesheat tolerant Eubacteria Animals, fungi, green plants Spirochaetes Iron bacteria, Archaea

  24. Trophic niche spaces in eukaryotes The specific trophic needs of organisms define their trophic niche. Trophic niches are generally not species specific. They are highly variable in time and space. Animals Consumers Carnivores Green plants Parasites Herbivores Producers Omnivores Fungivores Omnivores are animals that feed on other animals and plants LatinGreek Herbivore Phytophage Carnivore Zoophage FungivoreMycetophage Omnivore Pantophage SaprovoreSaprophage Microvore Microphage Bacteriovore Bacteriophage Mineralisers Saprovores Reducers Fungi, slime moulds, animals

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