INVESTIGADORES
CUSSAC Victor Enrique
artículos
Título:
Long term diet differences between morphs in trophically polymorphic Percichthys trucha (Pisces: Percichthyidae) populations from the southern Andes
Autor/es:
LOGAN, M.S.; S.J. IVERSON; D.E. RUZZANTE; S.J. WALDE; P.J. MACCHI; M.F. ALONSO; V.E. CUSSAC
Revista:
BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY
Referencias:
Año: 2000 vol. 69 p. 599 - 616
ISSN:
0024-4066
Resumen:
Divergent natural selection is often believed to be the driving force behind phenotypic
differentiation in characters related to resource acquisition, leading to trophic polymorphism
in fishes. Here we use variation in the fatty acid composition of adipose and muscle tissues
to look at differences in resource use by two recently described sympatric morphs of Percichthys
trucha, a common freshwater fish of the Andean and Patagonian regions of South America.
Because dietary fatty acids are often stored in carnivorous animals with little modification
after consumption, they can be used to infer information about dietary habits of individuals.
We found that the two morphs differed in the overall composition of fatty acids in both
adipose and muscle tissue, but that there were some differences in how the morphs differed
in lakes from the northern vs southern part of the range. Furthermore, we found that certain
fatty acids were correlated with diet as determined by gut content analysis. Consumption of
anisopteran larvae was highly correlated with 14:0 in adipose and muscle tissue; and higher
levels of longer chain unsaturated fatty acids (i.e. 20 and 22 carbons) were correlated with
the presence of fish and also amphipods in the diets. Taken together, the results suggest that
there are marked differences in the foraging ecology of the two morphs of P. trucha inhabiting
southern Andean lakes.fferentiation in characters related to resource acquisition, leading to trophic polymorphism
in fishes. Here we use variation in the fatty acid composition of adipose and muscle tissues
to look at differences in resource use by two recently described sympatric morphs of Percichthys
trucha, a common freshwater fish of the Andean and Patagonian regions of South America.
Because dietary fatty acids are often stored in carnivorous animals with little modification
after consumption, they can be used to infer information about dietary habits of individuals.
We found that the two morphs differed in the overall composition of fatty acids in both
adipose and muscle tissue, but that there were some differences in how the morphs differed
in lakes from the northern vs southern part of the range. Furthermore, we found that certain
fatty acids were correlated with diet as determined by gut content analysis. Consumption of
anisopteran larvae was highly correlated with 14:0 in adipose and muscle tissue; and higher
levels of longer chain unsaturated fatty acids (i.e. 20 and 22 carbons) were correlated with
the presence of fish and also amphipods in the diets. Taken together, the results suggest that
there are marked differences in the foraging ecology of the two morphs of P. trucha inhabiting
southern Andean lakes.fferences in resource use by two recently described sympatric morphs of Percichthys
trucha, a common freshwater fish of the Andean and Patagonian regions of South America.
Because dietary fatty acids are often stored in carnivorous animals with little modification
after consumption, they can be used to infer information about dietary habits of individuals.
We found that the two morphs differed in the overall composition of fatty acids in both
adipose and muscle tissue, but that there were some differences in how the morphs differed
in lakes from the northern vs southern part of the range. Furthermore, we found that certain
fatty acids were correlated with diet as determined by gut content analysis. Consumption of
anisopteran larvae was highly correlated with 14:0 in adipose and muscle tissue; and higher
levels of longer chain unsaturated fatty acids (i.e. 20 and 22 carbons) were correlated with
the presence of fish and also amphipods in the diets. Taken together, the results suggest that
there are marked differences in the foraging ecology of the two morphs of P. trucha inhabiting
southern Andean lakes., a common freshwater fish of the Andean and Patagonian regions of South America.
Because dietary fatty acids are often stored in carnivorous animals with little modification
after consumption, they can be used to infer information about dietary habits of individuals.
We found that the two morphs differed in the overall composition of fatty acids in both
adipose and muscle tissue, but that there were some differences in how the morphs differed
in lakes from the northern vs southern part of the range. Furthermore, we found that certain
fatty acids were correlated with diet as determined by gut content analysis. Consumption of
anisopteran larvae was highly correlated with 14:0 in adipose and muscle tissue; and higher
levels of longer chain unsaturated fatty acids (i.e. 20 and 22 carbons) were correlated with
the presence of fish and also amphipods in the diets. Taken together, the results suggest that
there are marked differences in the foraging ecology of the two morphs of P. trucha inhabiting
southern Andean lakes.ffered in the overall composition of fatty acids in both
adipose and muscle tissue, but that there were some differences in how the morphs differed
in lakes from the northern vs southern part of the range. Furthermore, we found that certain
fatty acids were correlated with diet as determined by gut content analysis. Consumption of
anisopteran larvae was highly correlated with 14:0 in adipose and muscle tissue; and higher
levels of longer chain unsaturated fatty acids (i.e. 20 and 22 carbons) were correlated with
the presence of fish and also amphipods in the diets. Taken together, the results suggest that
there are marked differences in the foraging ecology of the two morphs of P. trucha inhabiting
southern Andean lakes.fferences in how the morphs differed
in lakes from the northern vs southern part of the range. Furthermore, we found that certain
fatty acids were correlated with diet as determined by gut content analysis. Consumption of
anisopteran larvae was highly correlated with 14:0 in adipose and muscle tissue; and higher
levels of longer chain unsaturated fatty acids (i.e. 20 and 22 carbons) were correlated with
the presence of fish and also amphipods in the diets. Taken together, the results suggest that
there are marked differences in the foraging ecology of the two morphs of P. trucha inhabiting
southern Andean lakes.fferences in the foraging ecology of the two morphs of P. trucha inhabiting
southern Andean lakes.