Genetic Diversity and the Survival of Populations

Abstract

In this comprehensive review, a range of factors is considered that may influence the significance of genetic diversity for the survival of a population. Genetic variation is essential for the adaptability of a population in which quantitatively inherited, fitness-related traits are crucial. Therefore, the relationship between genetic diversity and fitness should be studied in order to make predictions on the importance of genetic diversity for a specific population. The level of genetic diversity found in a population highly depends on the mating system, the evolutionary history of a species and the population history (the latter is usually unknown), and on the level of environmental heterogeneity. An accurate estimation of fitness remains complex, despite the availability of a range of direct and indirect fitness parameters. There is no general relationship between genetic diversity and various fitness components. However, if a lower level of heterozygosity represents an increased level of inbreeding, a reduction in fitness can be expected. Molecular markers can be used to study adaptability or fitness, provided that they represent a quantitative trait locus (QTL) or are themselves functional genes involved in these processes. Next to a genetic response of a population to environmental change, phenotypic plasticity in a genotype can affect fitness. The relative importance of plasticity to genetic diversity depends on the species and population under study and on the environmental conditions. The possibilities for application of current knowledge on genetic diversity and population survival for the management of natural populations are discussed.

Adaptation - fitness - genetic diversity - life history characteristics - molecular markers - population history - population management - quantitative traits

References

• 01 Affre,  L., and Thompson,  J. D.. (1997);  Population genetic structure and levels of inbreeding depression in the Mediterranean island endemic Cyclamen creticum (Primulaceae).  Biol. J. Linn. Soc.. 60 527-549
• 02 Ager,  A.,, Guries,  G.,, and Lee,  C. H.. (1983) Genetic gains from red pine seedling seed orchards. Durham, New Hampshire; Proc. 28th Northeastern Forest Tree Improvement Conference
• 03 Ågren,  J., and Schemske,  D. F.. (1993);  Outcrossing and inbreeding depression in two annual monoecious herbs Begonia hirsuta and B. semiovata. .  Evolution. 47 125-135
• 04 Allard,  R. W., and Bradshaw,  A. D.. (1964);  Implications of genotype-environmental interactions in applied plant breeding.  Crop Sci.. 4 503-508
• 05 Allard,  R. W.,, Harding,  J.,, and Wehrhahn,  C.. (1966);  The estimation and use of selective values in predicting population change.  Heredity. 21 547-563
• 06 Allendorf,  F. W., and Leary,  R. F.. (1986) Heterozygosity and fitness in natural populations of animals. Conservation biology. The science of scarcity and diversity. Soulé, M. E., ed. Sunderland; Sinauer Associates Inc. pp. 57-76
• 07 Allendorf,  F. W., and Waples,  R. S.. (1996) Conservation and genetics of salmonoid fishes. Conservation genetics. Case histories from nature. Avise, J. C. and Hamrick, J. L., eds. New York; Chapman and Hall pp. 238-280
• 08 Alonso-Blanco,  C.,, Blankestijn-De Vries,  H.,, Hanhart,  C. J.,, and Koornneef,  M.. (1999);  Natural allelic variation at seed size loci in relation to other life history traits of Arabidopsis thaliana. .  Proc. Natl. Acad. Sci., USA. 96 4710-4717
• 09 Alvarez-Buylla,  E. R.,, Garcia-Barrios,  R.,, Lara-Moreno,  C.,, and Martinez-Ramos,  M.. (1996);  Demographic and genetic models in conservation biology: applications and perspectives for tropical rain forest tree species.  Ann. Rev. Ecol. Syst.. 27 387-421
• 10 Aravanopoulos,  F. A., and Zsuffa,  L.. (1998);  Heterozygosity and biomass production in Salix eriocephala. .  Heredity. 81 396-403
• 11 Arens,  P.,, Coops,  H.,, Jansen,  J.,, and Vosman,  B.. (1998);  Molecular genetic analysis of black poplar (Populus nigra L.) along Dutch rivers.  Mol. Ecol.. 7 11-18
• 12 Arnold,  S. J.. (1994) Multivariate inheritance and evolution: a review of concepts. Quantitative genetic studies of behavioral evolution. Boake, C. R. B., ed. Chicago; University of Chicago Press pp. 17-48
• 13 Barrett,  S. C. H., and Kohn,  J. R.. (1991) Genetic and evolutionary consequences of small population size in plants: implications for conservation. Genetics and conservation of rare plants. Falk, D. A. and Holsinger, K. E., eds. New York; Oxford University Press pp. 3-30
• 14 Barton,  N. H., and Turelli,  M.. (1989);  Evolutionary quantitative genetics: how little do we know?.  Ann. Rev. Genet.. 23 337-370
• 15 Bateson,  P. G.. (1983) Optimal outbreeding. Mate choice. Cambridge; Cambridge University Press pp. 257-309
• 16 Beacham,  T. D.. (1991);  Developmental stability, heterozygosity, and genetic analysis of morphological variation in pink salmon (Oncorhynchus gorbuscha). .  Can. J. Zool.. 69 274-278
• 17 Beardmore,  J. A.. (1983) Extinction, survival, and genetic variation. Genetics and conservation: a reference for managing wild animal and plant populations. Schonewald-Cox, C. M., Chambers, S. M., MacBryde, B., and Thomas, W. L., eds. Menlo Park, California; Benjamin/Cummings pp. 125 -151
• 18 Bell,  D. L., and Sultan,  S. E.. (1999);  Dynamic phenotypic plasticity for root growth in Polygonum: a comparative study.  Am. J. Bot.. 86 807-819
• 19 Bennington,  C. C., and McGraw,  J. B.. (1996);  Environment-dependence of quantitative genetic parameters in Impatiens pallida. .  Evolution. 50 1083-1097
• 20 Biémont,  C.. (1983);  Homeostasis, enzymatic heterozygosity, and inbreeding depression in natural populations of Drosophila melanogaster. .  Genetica. 61 179-189
• 21 Blum,  A.. (1996);  Crop responses to drought and the interpretation of adaptation.  Plant Growth Regulation. 20 135-148
• 22 Bonnell,  M. L., and Selander,  R. K.. (1974);  Elephant seals: genetic variation and near extinction.  Science. 134 908-909
• 23 Bradshaw,  A. D.. (1965);  Evolutionary significance of phenotypic plasticity in plants.  Adv. Genet.. 13 115-155
• 24 Brakefield,  P. M., and Saccheri,  I. J.. (1994) Guidelines in conservation genetics and the use of the population cage experiments with butterflies to investigate the effects of genetic drift and inbreeding. Conservation genetics. Loeschcke, V., Tomiuk, J., and Jain, S. K., eds. Basel; Birkhäuser Verlag pp. 165-179
• 25 Briscoe,  D. A.,, Malpica,  J. M.,, Robertson,  A.,, Smith,  G. J.,, Frankham,  R.,, Banks,  R. G.,, and Barker,  J. S. F.. (1992);  Rapid loss of genetic variation in large captive populations of Drosophila flies: implications for the genetic management of captive populations.  Cons. Biol.. 6 416-425
• 26 Britten,  H. B.. (1996);  Meta-analyses of the association between multilocus heterozygosity and fitness.  Evolution. 50 2158-2164
• 27 Brookes,  M. I.,, Graneau,  Y. A.,, King,  P.,, Rose,  O. C.,, Thomas,  C. D.,, and Mallet,  J. L. B.. (1997);  Genetic analysis of founder bottlenecks in the rare British butterfly Plebejus argus. .  Cons. Biol.. 11 648-661
• 28 Brown,  A. D. H.. (1990) Genetic characterization of plant mating systems. Plant population genetics, breeding, and genetic resources. Brown, A. D. H., Clegg, M. T., Kahler, A. L., and Weir, B. S., eds. Sunderland; Sinauer Associates Inc. pp. 145-162
• 29 Brown,  A. D. H., and Schoen,  D. J.. (1992) Plant population genetic structure and biological conservation. Conservation of biodiversity for sustainable development. Sandlund, O. T., Hindar, K., and Brown, A. H. D., eds. Oslo; Scandinavian University Press pp. 88-104
• 30 Brown,  A. H. D., and Weir,  B. S.. (1983) Measuring genetic variability in plant populations. Development in plant genetics and breeding 1. Isozymes in plant genetics and breeding. Part A. Tanksley, S. D. and Orton, T. J., eds. Amsterdam; Elsevier Science Publishers B. V. pp. 219-239
• 31 Brown,  J. H.,, Marquet,  P. A.,, and Taper,  M. L.. (1993);  Evolution of body size: consequences of an energetic definition of fitness.  Am. Nat.. 142 373-384
• 32 Browning,  J. A.. (1974);  Relevance of knowledge about natural ecosystems to development of pest management programs for agro-ecosystems.  Proc. Am. Phytopathol. Soc.. 1 191-199
• 33 Bryant,  E. H.,, Backus,  V. L.,, Clark,  M. E.,, and Reed,  D. H.. (1999);  Experimental tests of captive breeding for endangered species.  Cons. Biol.. 13 1487-1496
• 34 Bryant,  E. H.,, Combs,  L. M.,, and McCommas,  S. A.. (1986);  The effect of an experimental bottleneck upon quantitative genetic variation in the housefly.  Genetics. 114 1191-1211
• 35 Bryant,  E. H., and Meffert,  L. M.. (1990);  Multivariate phenotypic differentiation among bottleneck lines of the housefly.  Evolution. 44 660-668
• 36 Burdon,  J. J.. (1980);  Intra-specific diversity in a natural population of Trifolium repens. .  J. Ecol.. 68 717-735
• 37 Burdon,  J. J.. (1985) Pathogens and the genetic structure of plant populations. Studies on plant demography: a Festschrift for John L. Harper. White, J., ed. London; Academic Press pp. 313-325
• 38 Burdon,  J. J.. (1987) Diseases and plant population biology. Cambridge; Cambridge University Press
• 39 Burdon,  J. J., and Jarosz,  A. M.. (1990) Disease in mixed cultivars, composites, and natural plant populations: some epidemiological and evolutionary consequences. Plant population genetics, breeding, and genetic resources. Brown, A. D. H., Clegg, M. T., Kahler, A. L., and Weir, B. S., eds. Sunderland; Sinauer Associates Inc. pp. 215-228
• 40 Burnham-Curtis,  M. K,, Krueger,  C. C.,, Schreiner,  D. R.,, Johnson,  J. E.,, Stewart,  T. J.,, Horrall,  R. M.,, MacCallum,  W. R.,, Kenyon,  R.,, and Lange,  R. E.. (1995);  Genetic strategies for lake trout rehabilitation: a synthesis.  J. Great Lakes Res.. 21 (Suppl. 1) 477-486
• 41 Byers,  D. L., and Waller,  D. M.. (1999);  Do plant populations purge their genetic load? Effects of population size and mating history on inbreeding depression.  Ann. Rev. Ecol. Syst.. 30 479-513
• 42 Campbell,  D. R.. (1997);  Genetic and environmental variation in life history traits of a monocarpic perennial: a decade-long field experiment.  Evolution. 51 373-382
• 43 Carvalho,  G. R.. (1993);  Evolutionary aspects of fish distribution: genetic variability and adaptation.  J. Fish Biol.. 43 (Suppl. A) 53-73
• 44 Case,  T. J., and Taper,  M. L.. (1986);  On the coexistence and coevolution of asexual and sexual competitors.  Evolution. 40 366-387
• 45 Charlesworth,  D.. (1991);  The apparent selection on neutral marker loci in partially inbreeding populations.  Genet. Res.. 57 159-175
• 46 Charlesworth,  D., and Charlesworth,  B.. (1987);  Inbreeding depression and its evolutionary consequences.  Ann. Rev. Ecol. Syst.. 18 237-268
• 47 Charlesworth,  D.,, Lyons,  E. E.,, and Litchfield,  L. B.. (1994);  Inbreeding depression in two highly inbreeding populations of Laevenworthia. .  Proc. R. Soc. Lond. B. 258 209-214
• 48 Charlesworth,  D.,, Morgan,  M. T.,, and Charlesworth,  B.. (1990);  Inbreeding depression, genetic load and the evolution of outcrossing rates in a multi-locus system with no linkage.  Evolution. 44 1469-1489
• 49 Chesser,  R. K., and Ryman,  N.. (1986);  Inbreeding strategy in subdivided populations.  Evolution. 40 616-624
• 50 Cheverud,  J.,, Routman,  E.,, Jaquish,  C.,, Tardif,  S.,, Peterson,  G.,, Belfiore,  N.,, and Forman,  L.. (1994);  Quantitative and molecular genetic variation in captive cotton-top tamarins (Saguinus oedipus). .  Cons. Biol.. 8 95-105
• 51 Clarke,  G. M.. (1992);  Fluctuating asymmetry: a technique for measuring developmental stress of genetic and environmental origin.  Acta Zool. Fenn.. 191 31-35
• 52 Clarke,  G. M.. (1993);  The genetic basis of developmental stability. I. Relationships between stability, heterozygosity and genomic coadaptation.  Genetica. 89 15-23
• 53 Clarke,  G. M.. (1995);  Relationships between developmental stability and fitness: application for conservation biology.  Cons. Biol.. 9 18-24
• 54 Clarke,  G. M.,, Brand,  G. W.,, and Whitten,  M. J.. (1986);  Fluctuating asymmetry: a technique for measuring developmental stress caused by inbreeding.  Austr. J. Biol. Sci.. 39 145-153
• 55 Clarke,  G. M., and McKenzie,  J. A.. (1987);  Developmental stability of insecticide resistant phenotypes in blowfly; a result of canalizing natural selection.  Nature. 325 345-346
• 56 Clarke,  G. M., and McKenzie,  J. A.. (1992);  Coadaptation, developmental stability and fitness of insecticide resistant genotypes in the Australian sheep blowfly, Lucilia cuprina: a review.  Acta Zool. Fenn.. 191 107-110
• 57 Clegg,  M. T.,, Kahler,  A. L.,, and Allard,  R. W.. (1978);  Estimation of life cycle components of selection in an experimental plant population.  Genetics. 89 765-792
• 58 Coltman,  D. W.,, Pilkington,  J. G.,, Smith,  J. A.,, and Pemberton,  J. M.. (1999);  Parasite-mediated selection against inbred Soay sheep in a free-living, island population.  Evolution. 53 1259-1267
• 59 David,  P.. (1997);  Modeling the genetic basis of heterosis: tests of alternative hypotheses.  Evolution. 51 1049-1057
• 60 David,  P.. (1998);  Heterozygosity-fitness correlations: new perspectives on old problems.  Heredity. 80 531-537
• 61 David,  P.,, Delay,  B.,, and Jarne,  P.. (1997);  Heterozygosity and growth in the marine bivalve Spisula ovalis: testing altenative hypotheses.  Genet. Res. Camb.. 70 215-223
• 62 Den Boer,  P. J.,, Szyszko,  J.,, and Vermeulen,  R.. (1993);  Spreading the risk of extinction by genetic diversity in populations of the carabid beetle Pterostichus oblongopunctatus F. (Coleoptera, Carbidae).  Neth. J. Zool.. 43 242-259
• 63 Deng,  H.-W., and Fin,  Y.-X.. (1998);  Conditions for positive and negative correlations between fitness and heterozygosity in equilibrium populations.  Genetics. 148 1333-1340
• 64 Dietl,  G., and Langhammer,  M.. (1997);  Conservation of rare breeds of animals - objectives and possibilities.  Arch. Tierz., Dummerstorf. 40 135-141
• 65 Dinus,  R. J.. (1974);  Knowledge about natural ecosystems as a guide to disease control in managed forests.  Proc. Am. Phytopathol. Soc.. 1 184-190
• 66 Dobson,  A., and Crawley,  M.. (1994);  Pathogens and the structure of plant communities.  Trends Ecol. Evol.. 9 393-398
• 67 Dobzhansky,  T.. (1951) Genetics and the origin of species. Third edition. New York; Colombia University Press
• 68 Ellegren,  H.,, Hartman,  G.,, Johansson,  M.,, and Andersson,  L.. (1993);  Major histocompatibility complex monomorphism and low levels of DNA fingerprinting variability in a reintroduced and rapidly expanding population of beavers.  Proc. Natl. Acad. Sci. USA. 90 8150-8153
• 69 Ellstrand,  N. C., and Elam,  D. R.. (1993);  Population genetic consequences of small population size: implications for plant conservation.  Ann. Rev. Ecol. Syst.. 24 217-242
• 70 Ellstrand,  N. C., and Roose,  M. L.. (1987);  Patterns of genotypic diversity in clonal plant species.  Am. J. Bot.. 74 123-131
• 71 Ennos,  R. A.. (1990) Detection and measurement of selection: genetic and ecological approaches. Plant population genetics, breeding, and genetic resources. Brown, A. D. H., Clegg, M. T., Kahler, A. L., and Weir, B. S., eds. Sunderland; Sinauer Associates Inc. pp. 200-214
• 72 Evans,  A. S., and Marshall,  M.. (1996);  Developmental instability in Brassica campestris (Cruciferae): fluctuating asymmetry of foliar and floral traits.  J. Evol. Biol.. 9 717-736
• 73 Falconer,  D. S.. (1981) Introduction to quantitative genetics. Second edition. New York; Longman
• 74 Foster Hünneke,  L.. (1991) Ecological implications of genetic variation in plant populations. Genetics and conservation of rare plants. Falk, D. A. and Holsinger, K. E., eds. New York; Oxford University Press pp. 31-44
• 75 Fowler,  K., and Whitlock,  M. C.. (1999);  The distribution of phenotypic variance with inbreeding.  Evolution. 53 1143-1156
• 76 Fox,  G. A.. (1995);  Tinkering with the tinkerer: pollution versus evolution.  Environ. Health Perspect.. 103 (Suppl. 4) 93-100
• 77 Frankham,  R.. (1995);  Inbreeding and extinction: a treshold effect.  Cons. Biol.. 9 792-799
• 78 Fry,  J. D.,, Nuzhdin,  S. V.,, Pasyukova,  E. G.,, and Mackay,  T. F. C.. (1998);  QTL mapping of genotype-environment interaction for fitness in Drosophila melanogaster. .  Genet. Res., Camb.. 71 133-141
• 79 Gallardo,  M. H., and Köhler,  N.. (1994);  Demographic changes and genetic losses in populations of a subterranean rodent (Ctenomys maulinus brunneus) affected by a natural catastrophe.  Z. Säugetierkunde. 59 358-365
• 80 Gallardo,  M. H.,, Köhler,  N.,, and Araneda,  C.. (1995);  Bottleneck effects in local populations of fossorial Ctenomys (Rodentia, Ctenomyidae) affected by vulcanism.  Heredity. 74 638-646
• 81 Gause,  G. F.. (1947);  Problems of evolution.  Trans. Conn. Acad. Sci.. 37 17-68
• 82 Gharrett,  A. J.. (1994);  Genetic dynamics of a small population system: a model applicable to interactions between hatchery and wild fish.  Aquacult. Fish. Managem.. 25 79-92
• 83 Gharrett,  A. J., and Smoker,  W. W.. (1993 a);  A perspective on the relative importance of genetic infrastructure in salmon populations to ocean ranching in Alaska.  Fish. Res.. 18 45-58
• 84 Gharrett,  A. J., and Smoker,  W. W.. (1993 b) Genetic components in life history traits contribute to population structure. Genetic conservation of salmonid fishes. Cloud, J. G. and Thorgaard, G. H., eds. New York; Plenum Press pp. 197-202
• 85 Giles,  B. E.. (1983);  A comparison of quantitative and biochemical variation in the wild barley Hordeum murinum. .  Evolution. 38 34-41
• 86 Gillespie,  J. H., and Turelli,  M.. (1989);  Genotype-environment interactions and the maintenance of polygenic variation.  Genetics. 121 129-138
• 87 Gilpin,  M. E.. (1987) Spatial structure and population vulnerability. Viable populations for conservation. Soulé, M. E., ed. Cambridge; Cambridge University Press pp. 125-139
• 88 Gilpin,  M. E., and Hanski,  I.. (1991) Metapopulation dynamics: empirical and theoretical investigations. London; Academic Press, Harcourt Brace Jovanovich Publishers p. 336
• 89 Gilpin,  M. E., and Soulé,  M. E.. (1986) Minimum viable populations: processes of species extinction. Conservation biology: the science of scarcity and diversity. Soulé, M. E., ed. Sunderland; Sinauer Associates Inc. pp. 19-34
• 90 Given,  D. R.. (1994) Principles and practice of plant conservation. London; Chapman and Hall
• 91 Godt,  M. J. W., and Hamrick,  J. L.. (1996);  Allozyme diversity in the endangered shrub Lindera melissifolia (Lauraceae) and its widespread congener Lindera benzoin. .  Can. J. For. Res.. 26 2080-2087
• 92 Godt,  M. J. W., and Hamrick,  J. L.. (1999);  Population genetic analysis of Elliottia racemosa (Ericaceae), a rare Georgia shrub.  Mol. Ecol.. 8 75-82
• 93 González-Candelas,  F., and Palacios,  C.. (1997) Analyzing molecular data for studies of genetic diversity. Molecular genetic techniques for plant genetic resources. Ayad, W. G., Hodgkin, T., Jaradat, A., and Rao, V. R., eds. Report of an IPGRI Workshop, 9 - 11 October, 1995, Rome, Italy; International Plant Genetic Resources Institute, Rome pp. 55-80
• 94 Goodnight,  C. J.. (1987);  On the effect of founder events on epistatic genetic variance.  Evolution. 41 80-91
• 95 Goodnight,  C. J.. (1988);  Epistasis and the effect of founder events on the additive genetic variance.  Evolution. 42 441-454
• 96 Graham,  J. H.. (1992);  Genomic coadaptation and developmental stability in hybrid zones.  Acta Zool. Fenn.. 191 121-132
• 97 Grashof-Bokdam,  C. J.,, Jansen,  J.,, and Smulders,  M. J. M.. (1998);  Dispersal patterns of Lonicera periclymenum determined by genetic analysis.  Mol. Ecol.. 7 165-174
• 98 Greenwood,  P. J.,, Harvey,  P. H.,, and Perrins,  C. M.. (1978);  Inbreeding and dispersal in the great tit.  Nature. 271 52-54
• 99 Gregorius,  H.-R.. (1989) The importance of genetic multiplicity for tolerance of atmospheric pollution. Genetic effects of air pollutants in forest tree populations. Scholz, F., Gregorius, H.-R., and Rudin, D., eds. Berlin; Springer-Verlag pp. 163-172
• 100 Grime,  J. P.. (1997);  Biodiversity and ecosystem function: the debate deepens.  Science. 277 1260-1261
• 101 Guttman,  S. I.. (1994);  Population genetic structure and ecotoxicology.  Environm. Health Persp.. 102 97-100
• 102 Haldane,  J. B. S.. (1930);  Theoretical genetics of autopolyploids.  J. Genet.. 22 359-373
• 103 Halley,  J., and Hoelzel,  A. R.. (1996) Simulation models of bottleneck events in natural populations. Molecular genetic approaches in conservation. Smith, T. B. and Wayne, R. K., eds. New York; Oxford University Press pp. 347-363
• 104 Hamilton,  W. D.. (1980);  Sex versus non-sex versus parasite.  Oikos. 35 282-290
• 105 Hamilton,  W. D.. (1982) Pathogens as causes of genetic diversity in their host populations. Population biology of infectious diseases. Anderson, R. M. and May, R. M., eds. Berlin; Springer-Verlag pp. 269-296
• 106 Hamrick,  J. L., and Godt,  M. J. W.. (1990) Allozyme diversity in plant species. Plant population genetics, breeding, and genetic resources. Brown, A. D. H., Clegg, M. T., Kahler, A. L., and Weir, B. S., eds. Sunderland; Sinauer Associates Inc. pp. 43-63
• 107 Hamrick,  J. L., and Godt,  M. J. W.. (1996) Conservation genetics of endemic plant species. Conservation genetics. Case histories from nature. Avise, J. C. and Hamrick, J. L., eds. New York; Chapman and Hall pp. 281-304
• 108 Hamrick,  J. L., and Nason,  J. D.. (1996) Consequences of dispersal in plants. Population dynamics in space and time. Rhodes, O. E., Chesser, R. H., and Smith, M. H., eds. Chicago; University of Chicago Press pp. 203-236
• 109 Hartl,  D. L., and Clark,  A. G.. (1997) Principles of Population Genetics. Third Edition. Sunderland; Sinauer Ass. p. 542
• 110 Harvey,  P. H., and Ralls,  K.. (1986);  Do animals avoid incest?.  Nature. 320 575-576
• 111 Hattemer,  H. H., and Müller-Starck,  G.. (1989);  Forest decline as an adaptational process.  Allg. Forst-Jagdztg.. 160 222-229
• 112 Hedgecock,  D.. (1994) Does variance in reproductive success limit effective population sizes of marine organisms?. Genetics and evolution of aquatic organisms. Beaumont, A. R., ed. London; Chapman and Hall pp. 122-134
• 113 Hedrick,  P. W.. (1987);  Genetic load and the mating system in homosporous ferns.  Evolution. 41 1282-1289
• 114 Hedrick,  P. W.,, Brussard,  P. F.,, Allendorf,  F. W.,, Beardmore,  J. A.,, and Orzack,  S.. (1986);  Protein variation, fitness, and captive propagation.  Zoo Biol.. 5 91-99
• 115 Heimann,  B., and Cussans,  G. W.. (1996);  The importance of seeds and sexual reproduction in the population biology of Cirsium arvense - a literature review.  Weed Res.. 36 493-503
• 116 Hoelzel,  A. R.,, Halley,  J.,, O'Brien,  S. J.,, Campagna,  C.,, Arnbom,  T.,, Le Boeuf,  B.,, Ralls,  K.,, and Dover,  G. A.. (1993);  Elephant seal genetic variation and the use of simulation models to investigate historical population bottlenecks.  J. Hered.. 84 443-449
• 117 Hoffmann,  A. A., and Merilä,  J.. (1999);  Heritable variation and evolution under favourable and unfavourable conditions.  Trends Ecol. Evol.. 14 96-101
• 118 Hoffmann,  A. A., and Parsons,  P. A.. (1991) Evolutionary genetics and environmental stress. Oxford; Oxford University Press
• 119 Holsinger,  K. E.. (1988);  Inbreeding depression doesn't matter: the genetic basis of mating system evolution.  Evolution. 42 1235-1244
• 120 Holtsford,  T. P., and Ellstrand,  N. C.. (1990);  Inbreeding depression in Clarkia tembloriensis (Onagraceae) populations with different natural outcrossing rates.  Evolution. 44 2031-2046
• 121 Hooper,  D., and Vitousek,  P. M.. (1997);  The effects of plant composition and diversity on ecosystem processes.  Science. 277 1302-1305
• 122 Houle,  D.. (1992);  Comparing evolvability and variability of quantitative traits.  Genetics. 130 195-204
• 123 Hurst,  L. D.. (1999);  The evolution of genomic anatomy.  Trends Ecol. Evol.. 14 108-112
• 124 Husband,  B., and Schemske,  D. W.. (1996);  Evolution of the magnitude and timing of inbreeding depression in plants.  Evolution. 50 54-70
• 125 Jain,  S. K.. (1976) Patterns of survival and microevolution in plant populations. Population genetics and ecology. Karlin, S. and Nevo, E., eds. New York; Academic Press pp. 49-89
• 126 Jayakar,  S. D.. (1970);  A mathematical model for interaction of gene frequencies in a parasite and its host.  Theor. Pop. Biol.. 1 140-164
• 127 Jones,  J. S.. (1987);  An asymmetrical view of fitness.  Nature. 325 298-299
• 128 Karp,  A.,, Edwards,  K. J.,, Bruford,  M.,, Funk,  S.,, Vosman,  B.,, Morgante,  M.,, Seberg,  O.,, Kremer,  A.,, Boursot,  P.,, Arctander,  P.,, Tautz,  D.,, and Hewitt,  G. M.. (1997);  Molecular technologies for biodiversity evaluation: opportunities and challenges.  Nature Biotech.. 15 625-628
• 129 Karhu,  A.,, Hurme,  P.,, Karjalainen,  M.,, Karvonen,  P.,, Kärkkäinen,  K.,, Neale,  D.,, and Savolainen,  O.. (1996);  Do molecular markers reflect patterns of differentiation in adaptive traits of conifers?.  Theor. Appl. Genet.. 93 215-221
• 130 Kimura,  M.. (1983) The Neutral Theory of Molecular Evolution. Cambridge; Cambridge University Press
• 131 Kobyliansky,  E., and Livshits,  G.. (1983);  Relationship between levels of biochemical heterozygosity and morphological variability in human populations.  Ann. Hum. Genet.. 47 215-223
• 132 Kopp,  R. L.,, Guttman,  S. I.,, and Wissing,  T. E.. (1992);  Genetic indicators of environmental stress in central mudminnow (Umbra limi) populations exposed to acid precipitation in the Adirondack mountains.  Environ. Toxicol. Chem.. 11 665-676
• 133 Kopp,  R. L.,, Wissing,  T. E.,, and Guttman,  S. I.. (1994);  Genetic indicators of environmental tolerance among fish populations exposed to acid deposition.  Biochem. Syst. Ecol.. 22 459-475
• 134 Kretzmann,  M. B.,, Gilmartin,  W. G.,, Meyer,  A.,, Zegers,  G. P.,, Fain,  S. R.,, Taylor,  B. F.,, and Costa,  D. P.. (1997);  Low genetic variability in the Hawaiian monk seal.  Cons. Biol.. 11 482-490
• 135 Lacy,  R. C.. (1992) The effects of inbreeding on isolated populations: are minimum viable population sizes predictable?. Conservation biology. The theory and practice of nature conservation, preservation and management. Fiedler, P. L. and Jain, S. K., eds. New York; Chapman and Hall Inc. pp. 277-296
• 136 Lande,  R.. (1976);  The maintenance of genetic variability by mutation in a polygenic character with linked loci.  Genet. Res.. 26 221-235
• 137 Lande,  R.. (1980);  Genetic variation and phenotypic evolution during allopatric speciation.  Am. Nat.. 116 463-479
• 138 Lande,  R.. (1988);  Genetics and demography in biological conservation.  Science. 241 1455-1460
• 139 Lande,  R., and Barrowclough,  G. F.. (1987) Effective population size, genetic variation, and their use in population management. Viable populations for conservation. Soulé, M. E., ed. Cambridge; Cambridge University Press pp. 87-123
• 140 Lande,  R., and Schemske,  D. W.. (1985);  The evolution of self fertilization and inbreeding depression in plants. I. Genetic models.  Evolution. 39 24-40
• 141 Lande,  R., and Shannon,  S.. (1996);  The role of genetic variation in adaptation and population persistence in a changing environment.  Evolution. 50 434-437
• 142 Le Boeuf,  B. J.. (1974);  Male-male competition and reproductive success in elephant seals.  Am. Zool.. 14 163-176
• 143 Leamy,  L.. (1984);  Morphometric studies in inbred and hybrid house mice. V. Directional and fluctuating asymmetry.  Am. Nat.. 123 579-593
• 144 Leamy,  L.. (1992);  Morphometric studies in inbred and hybrid house mice. VII. Heterosis in fluctuating asymmetry at different ages.  Acta Zool. Fenn.. 191 111-120
• 145 Leary,  R. F., and Allendorf,  F. W.. (1989);  Fluctuating asymmetry as an indicator of stress: implications for conservation biology.  Trends Ecol. Evol.. 4 214-217
• 146 Leary,  R. F.,, Allendorf,  F. W.,, and Knudsen,  K. L.. (1983);  Developmental stability and enzyme heterozygosity in rainbow trout.  Nature. 301 71-72
• 147 Leary,  R. F.,, Allendorf,  F. W.,, and Knudsen,  K. L.. (1984);  Superior developmental stability of heterozygotes at enzyme loci in salmonid fishes.  Am. Nat.. 124 540-551
• 148 Leary,  R. F.,, Allendorf,  F. W.,, and Knudsen,  K. L.. (1985);  Inheritance of meristic variation and the evolution of developmental stability in rainbow trout.  Evolution. 39 308-314
• 149 Ledig,  F. T.. (1986) Heterozygosity, heterosis, and fitness in outbreeding plants. Conservation biology. The science of scarcity and diversity. Soulé, M. E., ed. Sunderland; Sinauer Associates Inc. pp. 77-104
• 150 Ledig,  F. T.. (1992);  Human impacts on genetic diversity in forest ecosystems.  Oikos. 63 87-108
• 151 Leonard,  K. J.. (1977);  Selection pressures and plant pathogens.  Ann. N.Y. Acad. Sci.. 287 207-222
• 152 Leonard,  K. J., and Czochor,  R. J.. (1980);  Theory of genetic interactions among populations of plants and their pathogens.  Ann. Rev. Phytopathol.. 18 237-258
• 153 Lerner,  I. M.. (1954) Genetic homeostasis. New York; John Wiley and Sons
• 154 Leung,  L. K. P.,, Dickman,  C. R.,, and Moore,  L. A.. (1993);  Genetic variation in fragmented populations of an Australian rainforest rodent, Melomys cervinipes. .  Pacific Cons. Biol.. 1 58-65
• 155 Levin,  D. A.. (1981);  Dispersal versus gene flow in plants.  Ann. Mo. Bot. Gard.. 68 233-253
• 156 Levin,  D. A.. (1983) Plant parentage: an alternative view of the breeding structure of populations. Population biology: retrospect and prospect. King, C. E. and Dawson, P. S., eds. New York; Columbia University Press pp. 171-188
• 157 Levin,  D. A., and Kerster,  H. W.. (1974);  Gene flow in seed plants.  Evol. Biol.. 7 139-220
• 158 Linhart,  Y. B., and Grant,  M. C.. (1996);  Evolutionary significance of local genetic differentiation in plants.  Ann. Rev. Ecol. Syst.. 27 237-277
• 159 Lönn,  M.,, Prentice,  H. C.,, and Bengtsson,  K.. (1996);  Genetic structure, allozyme-habitat associations and reproductive fitness in Gypsophila fastigiata (Caryophyllaceae).  Oecologia. 106 308-316
• 160 Lynch,  M.. (1988);  The rate of polygenic mutation.  Genet. Res.. 51 137-148
• 161 Lynch,  M.. (1996) A quantitative-genetic perspective on conservation issues. Conservation genetics. Case histories from nature. Avise, J. C. and Hamrick, J. L., eds. New York; Chapman and Hall pp. 471-501
• 162 Lynch,  C. B.,, Sulzbach,  D. S.,, and Connolly,  M. S.. (1988);  Quantitative-genetic analysis of temperature regulation in Mus domesticus. IV. Pleiotropy and genotype-by-environment interactions.  Am. Nat.. 132 521-537
• 163 MacGillivray,  C. W., and Grime,  J. P.. (1995);  Testing predictions of the resistance and resilience of vegetation subjected to extreme events.  Funct. Ecol.. 9 640-649
• 164 Mátyás,  Cs.. (1989) Genetic and ecological constraints of adaptation. Voronezh, USSR; Proc. IUFRO Int. Symp. on Forest Genetics, Breeding and Physiology pp. 79-90
• 165 Mátyás,  Cs.. (1996);  Climatic adaptation of trees: rediscovering provenance tests.  Euphytica. 92 45-54
• 166 Mayo,  O.. (1971);  Rates of change in gene frequency in tetrasomic organisms.  Genetica. 42 329-337
• 167 Maywald,  F., and Weigel,  H. J.. (1997);  Biochemistry and molecular biology of heavy metal accumulation in higher plants.  Landbauforsch. Volkenrode. 47 103-126
• 168 Menges,  E. S.. (1992) Stochastic modeling of extinction in plant populations. Conservation biology. The theory and practice of nature conservation, preservation and management. Fiedler, P. L and Jain, S. K., eds. New York; Chapman and Hall Inc. pp. 253-275
• 169 Midgley,  G. F.,, Wand,  S. J. E.,, and Musil,  C. F.. (1998);  Repeated exposure to enhanced UV-B radiation in successive generations increases developmental instability (leaf fluctuating asymmetry) in a desert annual.  Plant Cell Environm.. 21 437-442
• 170 Milligan,  B. G.,, Leebens-Mack,  J.,, and Strand,  A. E.. (1994);  Conservation genetics: beyond the maintenance of marker diversity.  Mol. Ecol.. 3 423-435
• 171 Mitchell-Olds,  T.. (1996);  Genetic constraints on life-history evolution: quantitative-trait loci influencing growth and flowering in Arabidopsis thaliana. .  Evolution. 50 140-145
• 172 Mitton,  J. B.. (1994);  Molecular approaches to population biology.  Ann. Rev. Ecol. Syst.. 25 45-69
• 173 Mitton,  J. B., and Grant,  M. C.. (1984);  Associations among protein heterozygosity, growth rate, and developmental homeostasis.  Ann. Rev. Ecol. Syst.. 15 479-499
• 174 Møller,  A. P.. (1997);  Developmental stability and fitness: a review.  Am. Nat.. 149 916-932
• 175 Møller,  A. P.. (1998);  Developmental stability of plants and radiation from Chernobyl.  Oikos. 81 444-448
• 176 Møller,  A. P., and Swaddle,  J. P.. (1997) Developmental stability and evolution. Oxford; Oxford University Press
• 177 Monneveux,  P., and Belhassen,  E.. (1996);  The diversity of drought adaptation in the wide.  Plant Growth Regulation. 20 85-92
• 178 Moran,  G. F.,, Marshall,  D. R.,, and Muller,  W. J.. (1981);  Phenotypic variation and plasticity in the colonizing species Xanthium strumarium L. (Noogoora Burr.).  Aust. J. Biol. Sci.. 34 639-648
• 179 Mosseler,  A.. (1995) Red pine: a model for the loss of genetic diversity in trees. Population genetics and genetic conservation of forest trees. Baradat, Ph., Adams, W. T., and Müller-Starck, G., eds. Amsterdam; SPB Academic Publishing pp. 359-370
• 180 Müller-Starck,  G.. (1995) Genetic variation under extreme environmental conditions. Population genetics and genetic conservation of forest trees. Baradat, Ph., Adams, W. T., and Müller-Starck, G., eds. Amsterdam; SPB Academic Publishing pp. 201-210
• 181 Müller-Starck,  G., and Hattemer,  H. H.. (1989);  Genetic effects of environmental stress on old stands and young growth of beech (Fagus sylvatica). .  Forstarchiv. 60 17-22
• 182 Nei,  M.. (1973);  Analysis of gene diversity in subdivided populations.  Proc. Natl. Acad. Sci. USA. 70 3321-3323
• 183 Nei,  M.,, Maruyama,  T.,, and Chakraborty,  R.. (1975);  The bottleneck effect and genetic variability in populations.  Evolution. 29 1-10
• 184 Nei,  M., and Takahata,  N.. (1993);  Effective population size, genetic diversity, and coalescence time in subdivided populations.  J. Mol. Evol.. 37 240-244
• 185 Nevo,  E.. (1986) Pollution and genetic evolution in marine organisms: theory and practice. Environmental quality and ecosystem stability, Vol. III A/B. Dubinsky, Z. and Steinberger, Y., eds. Ramat-Gan; Bar-Ilan University Press pp. 841-848
• 186 Nevo,  E.,, Appelbaum-Elkaher,  I.,, Garty,  J.,, and Beiles,  A.. (1997);  Natural selection causes microscale allozyme diversity in wild barley and a lichen at “Evolution Canyon”, Mt. Carmel, Israel.  Heredity. 78 373-382
• 187 Nunney,  L.. (1993);  The influence of mating system and overlapping generations on effective population size.  Evolution. 47 1329-1341
• 188 Nunney,  L., and Campbell,  K. A.. (1993);  Assessing minimum viable population size: demography meets population genetics.  Trends Ecol. Evol.. 8 234-239
• 189 Nunney,  L., and Elam,  D. R.. (1994);  Estimating the effective population size of conserved populations.  Cons. Biol.. 8 175-184
• 190 O'Brien,  S. J.. (1994);  A role for molecular genetics in biological conservation.  Proc. Natl. Acad. Sci. USA. 21 5748-5755
• 191 O'Brien,  S. J., and Evermann,  J. F.. (1988);  Interactive influence of infectious disease and genetic diversity in natural populations.  Trends Ecol. Evol.. 3 254-259
• 192 O'Brien,  S. J.,, Joslin,  P.,, Smith III,  G. L.,, Wolfe,  R.,, Schaffer,  N.,, Heath,  E.,, Ott-Joslin,  J.,, Rawal,  P. P.,, Bhattacharjee,  K. K.,, and Martenson,  J. S.. (1987);  Evidence for African origins of founders of the Asiatic lion species survival plan.  Zoo Biol. . 6 99-116
• 193 O'Brien,  S. J.,, Roelke,  M. E.,, Marker,  L.,, Newman,  A.,, Winkler,  C. A.,, Meltzer,  D.,, Colly,  L.,, Evermann,  J. F.,, Bush,  M.,, and Wildt,  D. E.. (1985);  Genetic basis for species vulnerability in the cheetah (mortality and feline infectious peritonitis).  Science. 227 1428-1434
• 194 Ohta,  R.. (1971);  Associative overdominance caused by linked detrimental mutations.  Genet. Res.. 18 277-286
• 195 Oleksyn,  J.,, Prus-Glowacki,  W.,, Giertych,  M.,, and Reich,  P. B.. (1994);  Relation between genetic diversity and pollution impact in a 1912 experiment with East European Pinus sylvestris provenances.  Can. J. For. Res.. 24 2390-2394
• 196 Oostermeijer,  J. G. B.,, Van Eijck,  M. W.,, Van Leeuwen,  N. C.,, and Den Nijs,  J. C. M.. (1995);  Analysis of the relationship between allozyme heterozygosity and fitness in the rare Gentiana pneumonanthe L.  J. Evol. Biol.. 8 739-759
• 197 Ouborg,  N. J., and Van Treuren,  R.. (1997) Inbreeding depression, environmental stochasticity and population extinction in plants. The role of genetics in conserving small populations. Tew, T. E., Crawford, T. J., Spencer, J. W., Stevens, D. P., Usher, M. B., and Warren, J., eds. Petersborough; Joint Nature Conservation Committee pp. 143-154
• 198 Overton,  R. P., and Johnson,  L. C.. (1983) Red pine - potential for genetic improvement and observations on cone and seed production. Durham, New Hampshire; Proc. 28th Northeastern Forest Tree Improvement Conference
• 199 Packer,  C.,, Pusey,  A. E.,, Rowley,  H.,, Gilbert,  D. A.,, Martenson,  J.,, and O'Brien,  S. J.. (1991);  Case study of a population bottleneck: lions of the Ngorongoro Crater.  Cons. Biol.. 5 219-230
• 200 Palmer,  A. R., and Strobeck,  C.. (1986);  Fluctuating asymmetry: measurement, analysis, patterns.   Ann. Rev. Ecol. Syst.. 17 392-421
• 201 Pamilo,  P., and Pálsson,  S.. (1998);  Associative overdominance, heterozygosity and fitness.  Heredity. 81 381-389
• 202 Parker,  E. D., Jr.. (1979 a);  Ecological implications of clonal diversity in parthenogenetic morphospecies.  Amer. Zool.. 19 753-762
• 203 Parker,  E. D., Jr.. (1979 b);  Phenotypic consequences of parthenogenesis in Cnemidophorus lizards. I. Variability in parthenogenetic and sexual populations.  Evolution. 33 1150-1166
• 204 Parsons,  P. A.. (1990);  Fluctuating asymmetry: an epigenetic measure of stress.  Biol. Rev. Camb. Philosoph. Soc.. 65 131-145
• 205 Parsons,  P. A.. (1996 a);  Stress, resources, energy balances, and evolutionary change.  Evol. Biol.. 29 39-72
• 206 Parsons,  P. A.. (1996 b);  Conservation genetics: adaptation to stress and the preservation of genetic diversity.  Biol. J. Linn. Soc.. 58 471-482
• 207 Partridge,  L.. (1983) Non-random mating and offspring fitness. Mate Choice. Bateson, P. G., ed. Cambridge; Cambridge University Press pp. 227-255
• 208 Peet,  R.. (1974);  The measurement of species diversity.  Ann. Rev. Ecol. Syst.. 5 285-307
• 209 Pogson,  G. H., and Fevolden,  S. E.. (1998);  DNA heterozygosity and growth rate in the Atlantic cod Gadus murhua (L).  Evolution. 52 915-920
• 210 Pogson,  G. H., and Zouros,  E.. (1994);  Allozyme and RFLP heterozygosities as correlates of growth rate in the scallop Placopecten magellanicus: a test of the associative overdominance hypothesis.  Genetics. 137 221-231
• 211 Polans,  N. O., and Allard,  R. W.. (1989);  An experimental evaluation of the recovery potential of ryegrass populations from genetic stress resulting from restriction of population size.  Evolution. 43 1320-1323
• 212 Prentice,  H. C.,, Lönn,  M.,, Lefkovitch,  L. P.,, and Runyeon,  H.. (1995);  Associations between allele frequencies in Festuca ovina and habitat variation in the alvar grasslands on the Baltic island of Öland.  J. Ecol.. 83 391-402
• 213 Prout,  T.. (1969);  The estimation of fitness from population data.  Genetics. 63 949-967
• 214 Prus-Glowacki,  W.. (1991) Biochemical polymorphism. Developments in plant genetics and breeding. 3. Genetics of Scots pine. Giertych, M. and Mátyás, Cs., eds. Amsterdam; Elsevier Publishers pp. 73-86
• 215 Prus-Glowacki,  W., and Godzik,  St.. (1991);  Changes induced by zinc smelter pollution in the genetic structure of pine (Pinus sylvestris L.) seedling populations.  Silv. Genet.. 40 184-188
• 216 Prus-Glowacki,  W.,, Wojnicka-Poltorak,  A.,, Oleksyn,  J.,, and Reich,  P. B.. (1999);  Industrial pollutants tend to increase genetic diversity: evidence from field-grown European Scots pine populations.  Water Air Soil Poll.. 116 395-402
• 217 Quattro,  J. M., and Vrijenhoek,  R. C.. (1989);  Fitness differences among remnant populations of the Sonoran topminnow, Poeciliopsis occidentalis. .  Science. 245 976-978
• 218 Qvarnström,  A.. (1999);  Genotype-by-environment interactions in the determination of the size of a secondary sexual character in the collared flycatcher (Ficedula albicollis). .  Evolution. 53 1564-1572
• 219 Rabinowitz,  D.. (1981) Seven forms of rarity. The biological aspects of rare plant conservation. Synge, H., ed. New York; John Wiley and Sons pp. 205-217
• 220 Rankevich,  D.,, Lavie,  B.,, Nevo,  E.,, Beiles,  A.,, and Arad,  Z.. (1996);  Genetic and physiological adaptations of the prosobranch landsnail Pomatia olivieri to microclimatic stresses on Mount Carmel, Israel.  Isr. J. Zool.. 42 425-441
• 221 Rausher,  M. D.. (1996);  Genetic analysis of coevolution between plants and their natural enemies.  Trends in Genetics. 12 212-217
• 222 Rice,  W. R.. (1983);  Parent-offspring pathogen transmission: a selective agent promoting sexual reproduction.  Am. Nat.. 121 187-203
• 223 Rick,  C. M.. (1983) Evolution of mating systems: evidence from allozyme variation. Genetics: new frontiers. Proc. XV Int. Congress of Genetics, New Dehli, India, December 12-21, 1983. New Dehli; Oxford and IBH Publishing pp. 215-221
• 224 Ritland,  K.. (1996);  A marker-based method for inferences about quantitative inheritance in natural populations.  Evolution. 50 1062-1073
• 225 Roff,  D. A.. (1998);  Evolution of treshold traits: the balance between directional selection, drift and mutation.  Heredity. 80 25-32
• 226 Saccheri,  I.,, Kuusaari,  M.,, Kankare,  M.,, Vikman,  P.,, Fortelius,  W.,, and Hanski,  I.. (1998);  Inbreeding and extinction in a butterfly metapopulation.  Nature. 392 491-494
• 227 Sarukhán,  J.,, Martinez-Ramos,  M.,, and Pinero,  D.. (1984) The analysis of demographic variability at the individual level and its population consequences. Perspectives on plant population ecology. Dirzo, R. and Sarukhán, J., eds. Sunderland; Sinauer Associates Inc. pp. 83-106
• 228 Schaal,  B. A.,, Leverich,  W. J.,, and Rogstad,  S. H.. (1991) A comparison of methods for assessing genetic variation in plant conservation biology. Genetics and conservation of rare plants. Falk, D. A. and Holsinger, K. E., eds. New York; Oxford University Press pp. 123-134
• 229 Scheiner,  S. M.. (1993);  Genetics and evolution of phenotypic plasticity.  Ann. Rev. Ecol. Syst.. 23 1-14
• 230 Scheiner,  S. M., and Lyman,  R. F.. (1989);  The genetics of phenotypic plasticity and genetic variation in populations of the grass Danthonia spicata. .  Evolution. 38 845-855
• 231 Schemske,  D. W.,, Husband,  B. C.,, Ruckelshaus,  M. H.,, Goodwillie,  C.,, Parker,  I. M.,, and Bishop,  J. G.. (1994);  Evaluating approaches to the conservation of rare and endangered plants.  Ecology. 75 584-606
• 232 Schlichting,  C. D.. (1986);  The evolution of phenotypic plasticity in plants.  Ann. Rev. Ecol. Syst.. 17 667-693
• 233 Schneller,  J. J., and Holderegger,  R.. (1996);  Genetic variation in small, isolated fern populations.  J. Veget. Sci.. 7 113-120
• 234 Shaffer,  M. L.. (1981);  Minimum population sizes for species conservation.  BioScience. 31 131-134
• 235 Shaffer,  M. L.. (1987) Minimum viable populations: coping with uncertainty. Viable populations for conservation. Soulé, M. E., ed. Cambridge; Cambridge University Press pp. 69-86
• 236 Sherry,  R. A., and Lord,  E. M.. (1996);  Developmental stability in leaves of Clarkia tembloriensis (Onagraceae) as related to population outcrossing rates and heterozygosity.  Evolution. 50 80-91
• 237 Shook,  D. R., and Johnson,  T. E.. (1999);  Quantitative trait loci affecting survival and fertility-related traits in Caenorhabditis elegans show genotype-environment interactions, pleiotropy and epistasis.  Genetics. 153 1233-1243
• 238 Silander,  J. A.. (1979);  Microevolution and clone structure in Spartina patens. .  Science. 203 658-660
• 239 Simmons,  M. J., and Crow,  J. F.. (1977);  Mutations affecting fitness in Drosophila populations.  Ann. Rev. Genet.. 11 49-78
• 240 Slate,  J.,, Pemberton,  J. M.,, and Visscher,  P. M.. (1999);  Power to detect QTL in a free-living polygynous population.  Heredity. 83 327-336
• 241 Slatkin,  M.. (1987);  Gene flow and the geographic structure of natural populations.  Science. 236 787-792
• 242 Smouse,  P. E.. (1986);  The fitness consequences of multiple-locus heterozygosity under the multiplicative overdominance and inbreeding depression models.  Evolution. 40 946-957
• 243 Solbrig,  O. T., and Simpson,  B. B.. (1974);  Components of regulation of a population of dandelions in Michigan.  J. Ecol.. 62 473-486
• 244 Soulé,  M. E.. (1980) Thresholds for survival: maintaining fitness and evolutionary potential. Conservation biology. An evolutionary-ecological perspective. Soulé, M. E. and Wilcox, B. A., eds. Sunderland; Sinauer Ass. pp. 151-169
• 245 Steiner,  E., and Levin,  D. A.. (1977);  Allozyme, SI gene, cytological and morphological polymorphisms in a population of Oenothera biennis. .  Evolution. 31 127-133
• 246 Storfer,  A.. (1996);  Quantitative genetics: a promising approach for the assessment of genetic variation in endangered species.  Trends Ecol. Evol.. 11 343-348
• 247 Strauss,  R. E.. (1991);  Correlations between heterozygosity and phenotypic variability in Cottus (Teleostei: Cottidae): character components.  Evolution. 45 1950-1956
• 248 Strauss,  S. H.. (1986);  Heterosis at allozyme loci under inbreeding and crossbreeding in Pinus attenuata. .  Genetics. 113 115-134
• 249 Sultan,  S. E.. (1987);  Evolutionary implications of phenotypic plasticity in plants.  Evol. Biol.. 21 127-178
• 250 Sultan,  S. E., and Bazzaz,  F. A.. (1993);  Phenotypic plasticity in Polygonum persicaria. II. Norms of reaction to soil moisture and the maintenance of genetic diversity.  Evolution. 47 1032-1049
• 251 Sun,  M.. (1997);  Genetic diversity in three colonizing orchids with contrasting mating systems.  Am. J. Bot.. 84 224-232
• 252 Templeton,  A. R.. (1982) The prophecies of parthenogenesis. Evolution and genetics of life histories. Dingle, H. and Hegmann, J. P., eds. New York; Springer-Verlag pp. 75-101
• 253 Templeton,  A. R.. (1994);  Biodiversity at the molecular genetic level: experiences from disparate macroorganisms.  Phil. Trans. R. Soc. Lond. B. 345 59-64
• 254 Templeton,  A. R., and Read,  B.. (1994) Inbreeding: one word, several meanings, much confusion. Conservation genetics. Loeschcke, V., Tomiuk, J., and Jain, S. K., eds. Basel; Birkhäuser Verlag pp. 91-105
• 255 Tilman,  D.,, Knops,  J.,, Wedin,  D.,, Reich,  P.,, Ritchie,  M.,, and Siemann,  E.. (1997);  The influence of functional diversity and composition on ecosystem processes.  Science. 277 1300-1302
• 256 Travis,  S. E.,, Maschinski,  J.,, and Keim,  P.. (1996);  An analysis of genetic variation in Astragalus cremnophylax var. cremnophylax, a critically endangered plant, using AFLP markers.  Mol. Ecol.. 5 735-745
• 257 Van Groenendael,  J. M.,, Ouborg,  N. J.,, and Hendriks,  R. J. J.. (1998);  Criteria for the introduction of plant species.  Acta Bot. Neerl.. 47 3-13
• 258 Van Noordwijk,  A. J.,, Van Tienderen,  P. H.,, De Jong,  G.,, and Van Balen,  J. H.. (1985);  Genealogical evidence for random mating in a natural population of the great tit (Parus major L.).  Naturwissenschaften. 72 104
• 259 Van Rossum,  F.,, Vekemans,  X.,, Meerts,  P.,, Gratia,  E.,, and Lefèbvre,  C.. (1997);  Allozyme variation in relation to ecotypic differentiation and population size in marginal populations of Silene nutans. .  Heredity. 78 552-560
• 260 Van Valen,  L.. (1962);  A study of fluctuating asymmetry.  Evolution. 16 125-142
• 261 Van Valen,  L.. (1965);  Morphological variation and width of ecological niche.  Am. Nat.. 99 377-390
• 262 Via,  S., and Lande,  R.. (1985);  Genotype-environment interaction and the evolution of phenotypic plasticity.  Evolution. 39 505-522
• 263 Via,  S., and Lande,  R.. (1987);  Evolution of genetic variability in a spatially heterogeneous environment: effects of genotype-environment interaction.  Genet. Res.. 49 147-156
• 264 Vrijenhoek,  R. C.. (1994) Genetic diversity and fitness in small populations. Conservation genetics. Loeschcke, V., Tomiuk, J., and Jain, S. K., eds. Basel; Birkhäuser Verlag pp. 37-53
• 265 Vrijenhoek,  R. C.. (1996) Conservation genetics of North America desert fishes. Conservation genetics. Case histories from nature. Avise, J. C. and Hamrick, J. L., eds. New York; Chapman and Hall pp. 367-397
• 266 Wallace,  B.. (1970) Genetic load: its biological and conceptual aspects. Engelwood Cliffs; Prentice-Hall
• 267 Wardle,  D. A.,, Zackrisson,  O.,, Hörnberg,  G.,, and Gallet,  C.. (1997);  The influence of island area on ecosystem properties.  Science. 277 1296-1299
• 268 Warwick,  S. I.,, Thompson,  B. K.,, and Black,  L. D.. (1987);  Life history and allozyme variation in populations of the weed species Setaria faberi. .  Can. J. Bot.. 65 1396-1402
• 269 Watkinson,  A. R., and Powell,  J. C.. (1993);  Seedling recruitment and the maintenance of clonal diversity in plant populations - a computer simulation of Ranunculus repens. .  J. Ecol.. 81 707-717
• 270 Weber,  J. L., and Wong,  C.. (1993);  Mutation of humans short tandem repeats.  Human Mol. Genet.. 2 1123-1128
• 271 Weir,  B. S.. (1989) Sampling properties of gene diversity. Plant population genetics, breeding, and genetic resources. Brown, A. D. H., Clegg, M. T., Kahler, A. L., and Weir, B. S., eds. Sunderland; Sinauer Associates Inc. pp. 23-42
• 272 Willis,  J. H., and Orr,  H. A.. (1993);  Increased heritable variation following population bottlenecks: the role of dominance.  Evolution. 47 949-957
• 273 Willson,  M. F.. (1983) Plant Reproductive Ecology. New York; Wiley-Interscience
• 274 Willson,  M. F.. (1984) Mating patterns in plants. Perspectives on plant population ecology. Dirzo, R. and Sarukhán, J., eds. Sunderland; Sinauer Associates Inc. pp. 261-277
• 275 Wilsey,  B. J.,, Haukioja,  E.,, Koricheva,  J.,, and Sulkinoja,  M.. (1998);  Leaf fluctuating asymmetry increases with hybridization and elevation in tree-line birches.  Ecology. 79 2092-2099
• 276 Winicov,  I.. (1998);  New molecular approaches to improving salt tolerance in crop plants.  Ann. Bot.. 82 703-710
• 277 Wright,  S.. (1965);  The interpretation of population structure by F-statistics with special regard to systems of mating.  Evolution. 19 395-420
• 278 Yang,  R.-C.,, Yeh,  F. C.,, and Yanchuk,  A. D.. (1996);  A comparison of isozyme and quantitative genetic variation in Pinus contorta ssp. latifolia by F_ST.  Genetics. 142 1045-1052
• 279 Yezerinac,  S. M.,, Lougheed,  S. C.,, and Handford,  P.. (1992);  Morphological variability and enzyme heterozygosity: individual and population level correlations.  Evolution. 46 1959-1964
• 280 Young,  A.,, Boyle,  T.,, and Brown,  T.. (1996);  The population genetic consequences of habitat fragmentation for plants.  Trends Ecol. Evol.. 11 413-418
• 281 Zink,  R. M.,, Smith,  M. F.,, and Patten,  J. L.. (1985);  Association between heterozygosity and morphological variance.  J. Hered.. 76 415-420
• 282 Zouros,  E., and Mallet,  A. L.. (1989) Genetic explanations of the growth/heterozygosity correlation. Reproduction, genetics and distributions of marine organisms: XXIII European Marine Biology Symposium. Ryland, J. S. and Tyler, P. A., eds. Fredensborg, Denmark; Olsen and Olsen pp. 317-324
• 283 Zouros,  E., and Pogson,  G. H.. (1994) The present status of the relationship between heterozygosity and heterosis. Genetics and evolution of aquatic organisms. Beaumont, A. R., ed. London; Chapman and Hall pp. 135-147

Section Editor: R. Aerts