Geoscience Reference
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Table 1 Alternative density-mass relationships reported in the literature
(following Reuman et al., 2008; White et al., 2007 )
Density mass relationship
Abbreviation
Classic references
Self-thinning or cross-community
scaling
CCSR
Yoda et al. (1963),
Westoby (1984)
Global size-density relationship
GSDR
Damuth (1981)
Local size-density relationship
LSDR
Marquet et al. (1990),
Gaton and Lawton (1988)
Individual size distribution or size
spectrum
ISD
Sheldon and Parson (1967)
Species mean-size
distribution
SMSD
Reuman et al. (2008)
community, guild, or population abundance across different times or locations
( White et al.,2007 ). These studies typically consider a single species ( Alunno-
Bruscia et al., 2000; Yoda et al.,1963 )orguilds( Gui˜ez and Castilla, 1999 )and
focus on space-limited systems, like plant assemblages ( Ellison, 1989; Westoby,
1984; Yoda et al.,1963 ) or intertidal communities ( Gui˜ez, 2005; Gui˜ez and
Castilla, 2001; Gui˜ez et al., 2005; Hughes andGriffiths, 1988 ). However, it has
also been observed for free-living animals ( Begon et al.,1986;Fr´chette and
Lefaivre, 1995 ) such as fishes ( Armstrong, 1997; Dunham et al., 2000; Elliott,
1993; Keeley, 2003; Steingr´msson and Grant, 1999 ), birds ( Meehan et al.,
2004 ), rodents ( White et al.,2004 ), as well as phytoplankton ( Li, 2002 ), and
unicellular communities ( Long and Morin, 2005 ).
Many analyses of the density-mass relationship and the observation of
patterns congruent with the energetic equivalence rule were based on abun-
dances collected from the literature ( Carbone and Gittleman, 2002; Damuth,
1981, 1987; Nee et al., 1991 ). This involves densities recorded in different
locations by different researchers, using different sampling procedures, and
probably biased towards those areas with higher abundances ( Currie, 1993;
Lawton, 1989 ). The frequent observation of a strong scaling pattern following
a power law with exponents of
1 (e.g. Carbone and Gittleman,
2002 ) is remarkable, taking into account the important sources of variation in
reported densities not directly connected to body size. The large scales at
which these analyses were performed lead to consider these studies as asses-
sing GSDR ( White et al., 2007 ). The energetic equivalence rule postulates that
there is no apriorienergetic advantage in being large in comparison to being
small ( Damuth, 1981 ). However, whether or not the scaling exponent compen-
sates for the increase in energetic demand with body size, it has been interpreted
as a local community attribute ( Currie and Fritz, 1993 ). However, the analysis
of DMR in local communities typically presents a large scatter ( Brown, 1995;
0.75 to
 
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