Geographical Areography

Rapoport, Eduardo H.

doi:10.1016/b978-0-08-028914-4.50012-6

Cited by 51 publications

(75 citation statements)

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“…The decline in richness in riverine birds at the highest altitudes also supports the evolutionary role of productivity and temperature on speciation because high altitude environments have low temperatures and low nutrient availability (Ward, 1998). Although increasingly subject to debate and doubt (Rahbek, 1997; Ruggiero & Lawton, 1998), such trends have been traditionally related to variations on Rapoport's rule, in which the latitudinal and altitudinal ranges of organisms decrease at lower latitudes and altitudes (Rapoport, 1982; Stevens, 1992).…”

Section: Discussionmentioning

confidence: 99%

Global patterns of diversity among the specialist birds of riverine landscapes

Buckton

Ormerod

2002

Freshwater Biology

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1. Despite the growing view that biodiversity provides a unifying theme in river ecology, global perspectives on richness in riverine landscapes are limited. As a result, there is little theory or quantitative data on features that might have influenced global patterns in riverine richness, nor are there clear indications of which riverine landscapes are important to conservation at the global scale. As conspicuous elements of the vertebrate fauna of riverine landscapes, we mapped the global distributions of all of the world's specialist riverine birds and assessed their richness in relation to latitude, altitude, primary productivity and geomorphological complexity (surface configuration). 2. Specialist riverine birds, typical of high‐energy riverine landscapes and dependent wholly or partly on production from river ecosystems, occur in 16 families. They are represented by an estimated 60 species divided equally between the passerines and non‐passerines. Major radiation has occurred among different families on different continents, indicating that birds have evolved several times into the niches provided by riverine landscapes. 3. Continental richness varies from four species in Europe to 28 in Asia, with richness on the latter continent disproportionately larger than would be expected from a random distribution with respect to land area. Richness is greatest in mountainous regions at latitudes of 20–40°N in the riverine landscapes of the Himalayan mountains, where 13 species overlap in range. 4. Family, genus and species richness in specialist riverine birds all increase significantly with productivity and surface configuration (i.e. relief). However, family richness was the best single predictor of the numbers of species or genera. In keeping with the effect of surface configuration, river‐bird richness peaks globally at 1300–1400 m altitude, and most species occur typically on small, fast rivers where they feed predominantly on invertebrates. Increased lengths of such streams in areas of high relief and rainfall might have been responsible for species–area effects. 5. We propose the hypothesis that the diversity in channel forms and habitats in riverine landscapes, in addition to high temperature and primary productivity, have been prerequisites to the development of global patterns in the richness of specialist riverine organisms. We advocate tests of this hypothesis in other taxonomic groups. We draw attention, however, to the challenges of categorically defining riverine organisms in such tests because (i) rivers grade into many other habitat types across several different ecotones and (ii) `terrestrialisation' processes in riverine landscapes means that they offer habitat for organisms whose evolutionary origins are not exclusively riverine.

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Section: Discussionmentioning

confidence: 99%

Global patterns of diversity among the specialist birds of riverine landscapes

Buckton

Ormerod

2002

Freshwater Biology

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“…First, while the majority of British bird species show signi®cant positive abun-dance±occupancy relationships, only a small minority are undergoing changes in distribution that are sucient to alter signi®cantly the position of Britain with respect to their wider geographical range. Secondly, it is not at all clear that declines in abundance and occupancy towards range limits are general features of species' distributions: while some studies claim to have shown this pattern (McClure & Price 1976;Hengeveld & Haeck 1981Brown 1984;Bart & Klosiewski 1989;Svensson 1992;TellerõÂ a & Santos 1993;Maurer 1994;Brown, Mehlman & Stevens 1995;Curnutt, Pimm & Maurer 1996), others have not (Rapoport 1982;Brussard 1984;Carter & Prince 1985;Wiens 1989). Of parti-cular relevance here, Blackburn et al (1999) failed to ®nd evidence that abundance declines towards the range edge in Britain for most of the 32 species of passerine birds they examined.…”

Section: (Ii) Range Position Explanationsmentioning

confidence: 99%

Abundance–occupancy relationships

Gaston

Blackburn

Greenwood

et al. 2000

Journal of Applied Ecology

731

692

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Summary1. The abundance and distribution of species tend to be linked, such that species declining in abundance often tend also to show declines in the number of sites they occupy, while species increasing in abundance tend also to be increasing in occupancy. Therefore, intraspeci®c abundance±occupancy relationships are commonly positive. 2. The intraspeci®c pattern is mirrored by more general positive interspeci®c abundance±occupancy relationships: widespread species tend to be abundant, and narrowly distributed species rare. 3. Here, we review recent research on these patterns based on the¯ora and fauna of the British Isles. We assess their generality, describe what is currently known about their structure, and summarize the results of tests of the several hypotheses proposed to explain their existence. 4. The positive form generally exhibited by abundance±occupancy relationships, intraspeci®c or interspeci®c, has consequences for several areas of applied ecology, including conservation, harvesting, biological invasions and biodiversity inventorying. These implications are discussed brie¯y.

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“…What areas of ranges should be the foci of conservation efforts? It is widely assumed that species reach their highest densities at the centre of their range and decline in density toward the range edges (Wulff, 1950; Andrewartha & Birch, 1954; Udvardy, 1969; Naumov, 1972; Kendeigh, 1974; Whittaker, 1975; Rapoport, 1982; Brown & Gibson, 1983; Cox & Moore, 1985; Hengeveld, 1990; Maurer et al ., 1994).…”

Section: Introductionmentioning

confidence: 99%

Geographical abundance distributions of coastal invertebrates: using one‐dimensional ranges to test biogeographic hypotheses

Sagarin

Gaines

2002

Journal of Biogeography

166

177

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Aim It is often assumed that species generally reach their highest densities in the centre of their range and decline in abundance towards the range edges. A number of mechanisms have been proposed that could theoretically support this pattern, and several ecological theories have been developed based on the assumption that this pattern occurs in nature. However, few studies have quantified geographical patterns of species abundance throughout species ranges. This is largely because of the logistical challenges of sampling throughout the large spatial areas of most species ranges. We use intertidal invertebrates, which have relatively well defined linear ranges, to test the hypothesis that species are most abundant in the centres of their ranges. Location Our sampling programme covered all or most of the ranges of twelve intertidal invertebrate species along the Pacific coast of North America, from Cabo San Lucas (Baja California, Mexico) to Shelikof Island (AK, USA). Method We sampled invertebrate density at forty‐two field sites using quadrat and transect methods. We used a shape fitting procedure to find idealized range shapes that best fit the sampled distributions of abundance. The idealized range shapes represented both a distribution where abundance was highest at the range centre and distributions where abundance was highest at one or both of the range edges. Results Overall, this suite of species did not show the expected pattern of high abundance near the range centre. Six of the species showed patterns indicative of high densities near one of their range edges, whereas only two showed patterns with high densities near their range centres. Furthermore, nine of the twelve species had sites near the range edges in which density ranked in the top 20% of all sites. Main conclusions The hypothesis that species are most abundant in the centre of their ranges cannot be generalized to this diverse suite of intertidal organisms. The diversity of distribution shapes that we found suggest that evolutionary and ecological theories that assume high abundance at range centres should be re‐examined with consideration of alternative abundance distributions. We suggest that sampled geographical distributions of abundance can be combined with demographic and physical factor data taken at the same scale to test hypotheses related to the causes of range boundaries and the responses of species ranges to climatic change.

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Geographical Areography

Cited by 51 publications

References 0 publications

Global patterns of diversity among the specialist birds of riverine landscapes

Global patterns of diversity among the specialist birds of riverine landscapes

Abundance–occupancy relationships

Geographical abundance distributions of coastal invertebrates: using one‐dimensional ranges to test biogeographic hypotheses

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