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Natural Growth Population Projections
1992With population projections future population size changes using present and past parameters and trends are estimated. The basic assumption of the underlying mathematical model is that some crucial demographic variables such as age-specific fertility and survival ratios remain unchanged.
Drago Čepar, Lojze Gosar, Erika Uršič
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Rickettsia Infection in Natural Leech Populations
Microbial Ecology, 2005Field-collected specimens of glossiphoniid leeches, Torix tagoi, Torix tukubana, Hemiclepsis marginata, and Hemiclepsis japonica, were surveyed for Rickettsia infection by using a diagnostic PCR assay. Rickettsia was detected in 96% (69/72) of T. tagoi, 83% (24/29) of T. tukubana, 29% (33/113) of H. marginata, and 0% (0/30) of H. japonica.
Y, Kikuchi, T, Fukatsu
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Quantitative genetic analysis of natural populations
Nature Reviews Genetics, 2002Quantitative genetic studies in natural populations have been rare because they require large breeding programmes or known pedigrees. The relatedness that has been estimated from molecular markers can now be used to substitute for breeding, allowing studies of previously inaccessible species.
Moore, Allen +2 more
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Natural Growth Population Models
1993Population projections by natural increase are studied. They forecast changes in population structure and size based on fertility, mortality and population age distribution, without considering migrations. In section 2, a well-known model of natural population growth based on one-year age-group data is described; in section 3, a simple, demonstrative ...
Drago Čepar, Erika Uršič
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Selection in Natural Populations
1997Abstract In 1974, Richard Lewontin published The Genetic Basis of Evolutionary Change, focusing enormous research attention on protein variation as both a model of underlying genetic variation and as a level of selection itself. Two decades later, scientific research has been shifted by the tremendous power of molecular biological ...
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Natural Resources and Growing Population
The Review of Economic Studies, 1975Ingham, A., Simmons, P.
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Selection in Natural Populations
2014This chapter discusses natural selection. Each species may be in one of two situations: it is well-adapted to its conditions of life, or it is poorly adapted to its conditions of life. In practice, of course, most species will fall between these two extremes: they are neither poorly adapted nor perfectly adapted.
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