Are there general laws in ecology

The dictionary definition of a law is: "Generalized formulation based on a series of events or processes observed to recur regularly under certain conditions; a widely observable tendency". I argue that ecology has numerous laws in this sense of the word, in the form of widespread, repeatable patterns in nature, but hardly any laws that are universally true. Typically, in other words, ecological patterns and the laws, rules and mechanisms that underpin them are contingent on the organisms involved, and their environment. This contingency is manageable at a relatively simple level of ecological organisation (for example the population dynamics of single and small numbers of species), and re-emerges also in a manageable form in large sets of species, over large spatial scales, or over long time periods, in the form of detail-free statistical patterns - recently called 'macroecology'. The contingency becomes overwhelmingly complicated at intermediate scales, characteristic of community ecology, where there are a large number of case histories, and very little other than weak, fuzzy generalisations. These arguments are illustrated by focusing on examples of typical studies in community ecology, and by way of contrast, on the macroecological relationship that emerges between local species richness and the size of the regional pool of species. The emergent pattern illustrated by local vs regional richness plots is extremely simple, despite the vast number of contingent processes and interactions involved in its generation. To discover general patterns, laws and rules in nature, ecology may need to pay less attention to the 'middle ground' of community ecology, relying less on reductionism and experimental manipulation, but increasing research efforts into macroecology.

[1]  Mats Gyllenberg,et al.  Uniting Two General Patterns in the Distribution of Species , 1997, Science.

[2]  L. Milne,et al.  The Balance of Nature , 1953, Oryx.

[3]  D. Pearson A Pantropical Comparison of Bird Community Structure on Six Lowland Forest Sites , 1977 .

[4]  G. Sugihara How Do Species Divide Resources? , 1989, The American Naturalist.

[5]  The relationship between local and regional species richness : comparing biotas with different evolutionary histories , 1997 .

[6]  H. Zwölfer Species richness, species packing, and evolution in insect-plant systems. , 1987 .

[7]  O. Eriksson The species-pool hypothesis and plant community diversity , 1993 .

[8]  J. Lawton There Are Not 10 Million Kinds of Population Dynamics , 1992 .

[9]  J. T.R. Sharrock,et al.  The Atlas of Breeding Birds in Britain and Ireland , 1980 .

[10]  O. Pellmyr Plant-Animal Interactions: Evolutionary Ecology in Tropical and Temperate Regions , 1991 .

[11]  J. Lawton,et al.  Community variability increases with time , 1997 .

[12]  W. L. The Balance of Nature , 1870, Nature.

[13]  H. Cornell Local and Regional Richness of Cynipine Gall Wasps on California Oaks , 1985 .

[14]  S. Compton,et al.  African fig wasp communities : undersaturation and latitudinal gradients in species richness , 1992 .

[15]  R. Freckleton,et al.  The Ecological Detective: Confronting Models with Data , 1999 .

[16]  E. Pianka Latitudinal Gradients in Species Diversity: A Review of Concepts , 1966, The American Naturalist.

[17]  J. Lawton Community ecology in a changing world , 2000 .

[18]  Joel E. Cohen,et al.  Food web patterns and their consequences , 1991, Nature.

[19]  E. Berlow,et al.  The Keystone Species Concept: Variation in Interaction Strength in a Rocky Intertidal Habitat , 1994 .

[20]  S. McNaughton,et al.  Ecosystem-level patterns of primary productivity and herbivory in terrestrial habitats , 1989, Nature.

[21]  Paul A. Keddy,et al.  Assembly and response rules: two goals for predictive community ecology , 1992 .

[22]  D. Currie Energy and Large-Scale Patterns of Animal- and Plant-Species Richness , 1991, The American Naturalist.

[23]  T. Case Global patterns in the establishment and distribution of exotic birds , 1996 .

[24]  S. Juliano,et al.  Evidence for the influence of historical processes in co-occurrence and diversity of tiger beetle species , 1993 .

[25]  T. Fenchel,et al.  Local versus global diversity of microorganisms : cryptic diversity of ciliated protozoa , 1997 .

[26]  D. Schluter,et al.  THE RELATIONSHIP BETWEEN LOCAL AND REGIONAL DIVERSITY , 1997 .

[27]  B. A. Maurer Geographical Population Analysis: Tools for the Analysis of Biodiversity , 1994 .

[28]  C. N. Slobodchikoff,et al.  A New Ecology: Novel Approaches to Interactive Systems , 1984 .

[29]  G. Fernandes,et al.  Plant--Animal Interactions: Evolutionary Ecology in Tropical and Temperate Regions , 1992 .

[30]  Roy M. Anderson,et al.  Population dynamics: The 20th symposium of the British Ecological Society, London, 1978 , 1979 .

[31]  K Roy,et al.  Marine latitudinal diversity gradients: tests of causal hypotheses. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[32]  Erkki Korpimäki,et al.  Population oscillations of boreal rodents: regulation by mustelid predators leads to chaos , 1993, Nature.

[33]  R. Ricklefs,et al.  Community Diversity: Relative Roles of Local and Regional Processes , 1987, Science.

[34]  J. Lawton,et al.  Species interactions, local and regional processes, and limits to the richness of ecological communities : a theoretical perspective , 1992 .

[35]  R. Macarthur,et al.  The Theory of Island Biogeography , 1969 .

[36]  B. Rørslett Principal determinants of aquatic macrophyte richness in northern European lakes , 1991 .

[37]  M. Carroll The Belknap Press of Harvard University Press , 1970 .

[38]  E. Roe Ecological Science and Statistical Paradigms , 1998, Science.

[39]  H. Cornell Unsaturation and regional influences on species richness in ecological communities: A review of the evidence , 1999 .

[40]  J. Lawton,et al.  Why More Productive Sites Have More Species: An Experimental Test of Theory Using Tree‐Hole Communities , 1998, The American Naturalist.

[41]  F. W. Preston The Canonical Distribution of Commonness and Rarity: Part I , 1962 .

[42]  L. G. Abele 9. Biogeography, Colonization, and Experimental Community Structure of Coral-Associated Crustaceans , 1984 .

[43]  R. Gillespie,et al.  Spiders in ecological webs , 1993 .

[44]  The investigation of saturation in the species richness of communities: some comments on methodology , 1995 .

[45]  John A. Wiens,et al.  The Ecology Of Bird Communities , 1989 .

[46]  D. Currie,et al.  Global patterns of tree species richness in moist forests : another look , 1998 .

[47]  D. Jablonski,et al.  Paleobiology, community ecology, and scales of ecological pattern. , 1996, Ecology.

[48]  A. Brower,et al.  Explaining the latitudinal gradient anomaly in ichneumonid species richness: evidence from butterflies , 1998 .

[49]  G. Hartvigsen Metapopulation biology: Ecology, genetics, and evolution , 1997 .

[50]  J. Richardson The Canonical Distribution. , 1945 .

[51]  Earl D. McCoy,et al.  The Statistics and Biology of the Species-Area Relationship , 1979, The American Naturalist.

[52]  Gonzalez,et al.  Metapopulation dynamics, abundance, and distribution in a microecosystem , 1998, Science.

[53]  R. Paine,et al.  Food-web analysis through field measurement of per capita interaction strength , 1992, Nature.

[54]  Robert D. Holt,et al.  7 – From Metapopulation Dynamics to Community Structure: Some Consequences of Spatial Heterogeneity , 1997 .

[55]  R D Holt,et al.  Diverse and Contrasting Effects of Habitat Fragmentation , 1992, Science.

[56]  K. Gaston,et al.  Spatial patterns in the body sizes of bird species in the New World , 1996 .

[57]  L. Crowder,et al.  Predation: direct and indirect impacts on aquatic communities , 1988 .

[58]  Robert M. May,et al.  Patterns of Dynamical Behaviour in Single-Species Populations , 1976 .

[59]  Kevin J. Gaston,et al.  A critique for macroecology , 1999 .

[60]  H. Cornell Species Assemblages of Cynipid Gall Wasps are Not Saturated , 1985, The American Naturalist.

[61]  K. Rohde Latitudinal Gradients in Species Diversity. Area Matters, but How Much? , 1998 .

[62]  Robert M. May,et al.  Lifting the veil on abundance patterns , 1991, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[63]  B. Menge,et al.  Indirect Effects in Marine Rocky Intertidal Interaction Webs: Patterns and Importance , 1995 .

[64]  E. Pianka Latitudinal gradients in species diversity , 1989 .

[65]  H. Cornell,et al.  Species Richness of Reef-Building Corals Determined by Local and Regional Processes , 1996 .

[66]  David Tilman,et al.  Insect species diversity, abundance and body size relationships , 1996, Nature.

[67]  K. Gaston,et al.  How many species of pimplines (Hymenoptera: Ichneumonidae) are there in Costa Rica? , 1993, Journal of Tropical Ecology.

[68]  B. Shorrocks,et al.  Spatial patchiness and community structure: coexistence and guild size of drosophilids on ephemeral resources , 1987 .

[69]  J. Lawton,et al.  Interspecific abundance-range size relationships: An appraisal of mechanisms , 1997 .

[70]  H. Dawah,et al.  Structure of the parasitoid communities of grass-feeding chalcid wasps , 1995 .

[71]  M. Gilpin,et al.  Perturbation Experiments in Community Ecology: Theory and Practice , 1984 .

[72]  C. Margules,et al.  Effects of habitat fragmentation on carabid beetles: experimental evidence , 1998 .

[73]  Jean-François Guégan,et al.  Global scale patterns of fish species richness in rivers , 1995 .

[74]  Sharon K. Collinge,et al.  A conceptual model of land conversion processes: predictions and evidence from a microlandscape experiment with grassland insects , 1998 .

[75]  G. C. Stevens Dissection of the Species-Area Relationship Among Wood-Boring Insects and Their Host Plants , 1986, The American Naturalist.

[76]  D. Quicke,et al.  Latitudinal gradients in North American braconid wasp species richness and biology , 1995 .

[77]  K. N. Rabenold A Reversed Latitudinal Diversity Gradient in Avian Communities of Eastern Deciduous Forests , 1979, The American Naturalist.

[78]  James H. Brown,et al.  Macroecology: The Division of Food and Space Among Species on Continents , 1989, Science.

[79]  T. Oberdorff,et al.  Non-interactive fish communities in the coastal streams of North-western France , 1998 .

[80]  V. Brown,et al.  Multitrophic Interactions in Terrestrial Systems , 1997 .

[81]  Daniel Simberloff,et al.  Ecological Communities: Conceptual Issues and the Evidence , 1984 .

[82]  J. Lawton,et al.  Ant‐Herbivore Interactions: Reasons for the Absence of Benefits to a Fern with Foliar Nectaries Vanessa K. Rashbrook , 1992 .

[83]  D. Griffiths Local and regional species richness in North American lacustrine fish , 1997 .

[84]  D. Doak,et al.  The Keystone-Species Concept in Ecology and ConservationManagement and policy must explicitly consider the complexity of interactions in natural systems , 1993 .

[85]  R. P. McIntosh H. A. GLEASON'S ‘INDIVIDUALISTIC CONCEPT’ AND THEORY OF ANIMAL COMMUNITIES: A CONTINUING CONTROVERSY , 1995, Biological reviews of the Cambridge Philosophical Society.

[86]  M. Pärtel,et al.  The species pool and its relation to species richness : evidence from Estonian plant communities , 1996 .

[87]  Richard M. Cowling,et al.  Coexistence of Banksia species in southwestern Australia: the role of regional and local processes , 1995 .

[88]  Stephen R. Carpenter,et al.  Complex Interactions in Lake Communities , 2011, Springer New York.

[89]  J. Thomson,et al.  Bracken Biology and Management. , 1991 .

[90]  R. A. Kempton,et al.  Species diversity , 2001 .

[91]  Gareth Jones,et al.  The new atlas of breeding birds in Britain and Ireland 1988-1991 , 1993 .

[92]  R. Paine,et al.  Marine rocky shores and community ecology : an experimentalist's perspective , 1995 .

[93]  K. Gaston,et al.  Spatial patterns in the species richness of birds in the New World , 1996 .

[94]  J. Wootton,et al.  The Nature and Consequences of Indirect Effects in Ecological Communities , 1994 .

[95]  S. Hall,et al.  Food webs: theory and reality , 1993 .

[96]  S. Agate,et al.  Small is beautiful , 2003, English Today.

[97]  T. Schoener,et al.  EFFECTS OF TOP AND INTERMEDIATE PREDATORS IN A TERRESTRIAL FOOD WEB , 1994 .

[98]  K. Church,et al.  The Partridge: Pesticides, Predation and Conservation , 1986 .

[99]  ECOLOGICAL DIVERSIFICATION AND COMMUNITY STRUCTURE IN THE OLD WORLD LEAF WARBLERS (GENUS PHYLLOSCOPUS): A PHYLOGENETIC PERSPECTIVE , 1996, Evolution; international journal of organic evolution.

[100]  K. Rohde The larger area of the tropics does not explain latitudinal gradients in species diversity , 1997 .

[101]  R. Holt From Metapopulation Dynamics to Community Structure , 1997 .

[102]  James H. Brown,et al.  GRANIVORY IN A DESERT ECOSYSTEM: EXPERIMENTAL EVIDENCE FOR INDIRECT FACILITATION OF ANTS BY RODENTS' , 1984 .

[103]  B. Menge,et al.  Dection of Direct Versus Indirect Effects: Were Experiments Long Enough? , 1997, The American Naturalist.

[104]  M. Rosenzweig,et al.  Species Diversity and Latitudes: Listening to Area's Signal , 1997 .

[105]  James H. Brown,et al.  Community Structure of Desert Small Mammals: Comparisons Across Four Continents , 1996 .

[106]  Peter S. Maitland,et al.  The trophic cascade in lakes , 1998 .

[107]  J. Magnuson,et al.  Intercontinental Comparison of Small-Lake Fish Assemblages: The Balance between Local and Regional Processes , 1990, The American Naturalist.

[108]  H. Cornell,et al.  11. Local and Regional Processes as Controls of Species Richness , 1998 .

[109]  T. Tscharntke,et al.  Habitat Fragmentation, Species Loss, and Biological Control , 1994, Science.

[110]  R D Holt,et al.  Intraguild predation: The dynamics of complex trophic interactions. , 1992, Trends in ecology & evolution.

[111]  D. M. Newbery,et al.  M. A. Huston, Biological Diversity: the coexistence of species on changing landscapes . Cambridge University Press. ISBN 0-521-36930-4 (pbk). 681 + xix. pages. £24.95. , 1995, Journal of Tropical Ecology.

[112]  M. Zobel Plant species coexistence - the role of historical, evolutionary and ecological factors , 1992 .

[113]  H. Wilbur,et al.  EXPERIMENTAL ECOLOGY OF FOOD WEBS: COMPLEX SYSTEMS IN TEMPORARY PONDS , 1997 .

[114]  P. Keddy Applications of the Hertzsprung-Russell star chart to ecology: reflections on the 21(st) birthday of Geographical Ecology. , 1994, Trends in ecology & evolution.

[115]  N. Stork,et al.  Species number, species abundance and body length relationships of arboreal beetles in Bornean lowland rain forest trees , 1988 .

[116]  John A. Wiens,et al.  Species diversity in ecological communities: edited by Robert E. Ricklefs and Dolph Schluter University of Chicago Press, 1993. $105.00 hbk, $35.00 pbk (414 pages) ISBN 0 226 71822 0/0 226 71823 9 , 1994 .

[117]  Owen L. Petchey,et al.  Effects on population persistence: the interaction between environmental noise colour, intraspecific competition and space , 1997, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[118]  R. Fuller,et al.  Ornithological atlas data: a review of uses and limitations , 1998 .

[119]  J. Lawton,et al.  Insects on Plants , 1984 .

[120]  Ilkka Hanski,et al.  Specialist predators, generalist predators, and the microtine rodent cycle. , 1991 .

[121]  M. Westoby Biodiversity in Australia compared with other continents , 1994 .

[122]  David H. Wright,et al.  Species-energy theory: an extension of species-area theory , 1983 .

[123]  B. Hugueny,et al.  Unsaturated Fish Communities in African Rivers , 1995, The American Naturalist.

[124]  P. Keddy,et al.  Three competing models for predicting the size of species pools : a test using eastern North American wetlands , 1996 .

[125]  J. Castilla,et al.  Challenges in the Quest for Keystones , 1996 .

[126]  G. Craig Local and Regional , 2015 .

[127]  W. Sheehan,et al.  Parasitoid community ecology , 1994 .

[128]  K. Gaston,et al.  Some Methodological Issues in Macroecology , 1998, The American Naturalist.

[129]  T. Blackburn,et al.  Rapoport's rule: time for an epitaph? , 1998, Trends in ecology & evolution.

[130]  J. Halley Ecology, evolution and 1 f -noise. , 1996, Trends in ecology & evolution.

[131]  I. Hiscock Communities and Ecosystems , 1970, The Yale Journal of Biology and Medicine.

[132]  Spiller,et al.  Impact of a catastrophic hurricane on island populations , 1998, Science.

[133]  I. Hanski,et al.  Spatial dynamics of two competing specialist parasitoids in a host metapopulation , 1998 .

[134]  K. Gaston,et al.  Age, area and avian diversification , 1997 .

[135]  W. Murdoch,et al.  Three distinct types of dynamic behaviour shown by a single planktonic system , 1985, Nature.

[136]  D. Srivastava Using local–regional richness plots to test for species saturation: pitfalls and potentials , 1999 .

[137]  G. Sugihara Minimal Community Structure: An Explanation of Species Abundance Patterns , 1980, The American Naturalist.

[138]  M. Gilpin,et al.  Metapopulation Biology: Ecology, Genetics, and Evolution , 1997 .

[139]  P. Niemelä,et al.  Reversed latitudinal gradient in species richness of sawflies (Hymenoptera, Symphyta) , 1994 .

[140]  A. Sinclair,et al.  Population regulation in animals , 1989 .

[141]  M. Zobel,et al.  The relative of species pools in determining plant species richness: an alternative explanation of species coexistence? , 1997, Trends in ecology & evolution.

[142]  J. Aho,et al.  Parasite communities: patterns and processes , 1990 .

[143]  T. Schoener,et al.  LIZARDS REDUCE SPIDER SPECIES RICHNESS BY EXCLUDING RARE SPECIES , 1998 .

[144]  J. Aho Helminth communities of amphibians and reptiles: comparative approaches to understanding patterns and processes , 1990 .

[145]  B. Pavlik Species Diversity in Ecological Communities: Historical and Geographical Perspectives by R. E. Ricklefs, D. Schluter , 1995 .

[146]  N. Stenseth,et al.  Ecological mechanisms and landscape ecology , 1993 .

[147]  G. Perry,et al.  Anolis lizards of the Caribbean : ecology, evolution, and plate tectonics , 1997 .

[148]  Brian A. Maurer Ecological Science and Statistical Paradigms: At the Threshold , 1998, Science.

[149]  J. Lawton,et al.  Patterns in Body Size, Population Dynamics, and Regional Distribution of Bracken Herbivores , 1988, The American Naturalist.

[150]  J. Bernardo,et al.  Simplifying the Jargon of Community Ecology: A Conceptual Approach , 1996, The American Naturalist.

[151]  A. Magurran,et al.  Biological diversity : the coexistence of species on changing landscapes , 1994 .

[152]  J. Lawton Small Is Beautiful, and Very Strange , 1998 .

[153]  D Carlisle,et al.  Lifting the veil. , 1995, Nursing times.

[154]  Richard Law,et al.  Regional Species Pools and the Assembly of Local Ecological Communities , 1997 .

[155]  J. M. Cherrett,et al.  Ecological Concepts: The Contribution of Ecology to an Understanding of the Natural World , 1989 .

[156]  J. Lawton Patterns in Ecology , 1996 .

[157]  H. Cyr,et al.  Magnitude and patterns of herbivory in aquatic and terrestrial ecosystems , 1993, Nature.

[158]  J. Lawton,et al.  Patterns in the distribution and abundance of insect populations , 1988, Nature.

[159]  J. Guégan,et al.  Regional versus local helminth parasite richness in British freshwater fish: saturated or unsaturated parasite communities? , 1994, Parasitology.

[160]  Roy Haines-Young,et al.  Biogeography , 1992, Vegetatio.

[161]  K. Gaston Species-range size distributions: products of speciation, extinction and transformation , 1998 .

[162]  J. Lawton,et al.  Population abundances, geographic ranges and conservation: 1994 Witherby Lecture , 1996 .

[163]  Brian A. Maurer,et al.  Energy supply and patterns of species richness on local and regional scales , 1993 .

[164]  Peter Kareiva,et al.  Spatial ecology : the role of space in population dynamics and interspecific interactions , 1998 .

[165]  J. Lawton,et al.  INSECTS ON PLANTS. COMMUNITY PATTERNS AND MECHANISMS. , 1987 .

[166]  J. Lawton 6. Non-Competitive Populations, Non-Convergent Communities, and Vacant Niches: The Herbivores of Bracken , 1984 .

[167]  Robert M. May,et al.  Theoretical Ecology: Principles and Applications , 1977 .

[168]  B. Shorrocks,et al.  Explaining local species diversity , 1995, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[169]  M. Hill,et al.  Untangling Ecological Complexity , 2000 .

[170]  J. Kitchell Food Web Management , 1992 .

[171]  John H. Lawton,et al.  Corncrake Pie and Prediction in Ecology , 1996 .

[172]  T. Schoener,et al.  Devastation of prey diversity by experimentally introduced predators in the field , 1996, Nature.

[173]  Local and regional species-richness of bracken-feeding insects. , 1990 .

[174]  Mark V. Lomolino,et al.  Species Diversity in Space and Time. , 1996 .