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<DIV class=articleTitle><FONT size=3><STRONG>Marine
Ecology</STRONG></FONT></DIV>
<DIV id=publishedOnlineDate>Article first published online: 15 OCT 2010</DIV>
<DIV id=doi>DOI: 10.1111/j.1439-0485.2010.00408.x</DIV>
<DIV class=articleTitle><FONT size=3><STRONG></STRONG></FONT> </DIV>
<DIV class=articleTitle><FONT size=3><STRONG>Latitudinal variation in the
aerial/aquatic ratio of oxygen consumption of a </STRONG></FONT></DIV>
<DIV class=articleTitle><FONT size=3><STRONG>supratidal high rocky-shore
crab</STRONG></FONT></DIV>
<DIV id=cr1><FONT size=3><SUP>Marco A. Lardies1, </SUP><SUP>José Luis Muñoz2,3,
</SUP><SUP>Kurt A. Paschke4, </SUP><SUP>Francisco Bozinovic2</SUP></FONT></DIV>
<DIV class=affiliation><SUP>1</SUP> Departamento de Ciencias, Facultad de Artes
Liberales & Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibañez,
Diagonal Las Torres, Peñalolen, Santiago, Chile<SUP>2</SUP> Center for Advanced
Studies in Ecology and Biodiversity and Departamento de Ecología, Facultad de
Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago,
Chile<SUP>3</SUP> Present address: Departamento de Bioloxía Funcional e Ciencias
da Saúde, Universidad de Vigo, Vigo (Pontevedra), Spain<SUP>4</SUP> Instituto de
Acuicultura, Facultad de Ciencias, Universidad Austral de Chile, Puerto Montt,
Chile. Correspondence: Marco A. Lardies, Departamento de Ciencias, Facultad de
Artes Liberales & Facultad de Ingeniería y Ciencias, Universidad Adolfo
Ibañez, Diagonal Las Torres 2640, Peñalolen, Santiago, Chile. E-mail: <!--TODO: clickthrough URL--><A title="Link to email address"
href="mailto:marco.lardies@uai.cl" shape=rect><FONT
color=#007e8a>marco.lardies@uai.cl</FONT></A></DIV>
<DIV>
<H3>Abstract</H3>
<DIV class=para>
<P>The colonisation of the terrestrial environment by crustaceans is more
apparent in tropical latitudes because of the high diversity of semi-terrestrial
and terrestrial crabs. However, in temperate regions there are also great
numbers of crustaceans that inhabit ecological niches at the water–air
interface. Grapsidae crabs (Decopoda) are especially important in studies of
water-to-land transition as the family contains species occupying the intertidal
and adjacent regions. A way to evaluate the ability of intertidal invertebrates
to breathe air is to measure the aerial/aquatic oxygen consumption ratio. The
objective of this study was to test the effect of thermal variation on the
aquatic and aerial metabolism. We selected as study model the decopoda crab
<EM>Cyclograpsus cinereus</EM> Dana and utilised five populations of the species
spread over 2000 km along the Chilean coast. To determine the compensation
capacity in respiration with respect to latitude, we evaluated metabolic rate at
the same temperature in a common garden design in the laboratory, to examine the
extent to which variation in crab physiology is environmentally determined.
Whereas in our study, <EM>m</EM><SUB><FONT size=1>b</FONT></SUB> (body mass)
varied significantly with latitude, the difference in mass-independent
metabolism both in air and water persisted, indicating that observed differences
in MR (Metabolic Rate) were not an effect of differences in body size. We
demonstrated that <EM>C. cinereus</EM> is able to breath oxygen from air
and water as expected for an amphibious crab. Almost all the studied populations
of <EM>C. cinereus</EM> show a aerial/aquatic metabolism ratio near 1. The
pattern found indicates an increase in metabolic rate, both aerial and aquatic,
in low latitudes and therefore does not support the latitudinal compensation
hypothesis for temperate habitats. Finally, these kinds of studies are required
to make the necessary link between ecological physiology and macroecology and to
help develop a global understanding of organismal function in marine
systems.</P></DIV></FONT></DIV></BODY></HTML>