Artificial selection on allometry: change in elevation but not slope.
J Evol Biol
; 25(5): 938-48, 2012 May.
Article
em En
| MEDLINE
| ID: mdl-22404434
ABSTRACT
To what extent within-species (static) allometries constitute a constraint on evolution is the subject of a long-standing debate in evolutionary biology. A prerequisite for the constraint hypothesis is that static allometries are hard to change. Several studies have attempted to test this hypothesis with artificial-selection experiments, but their results remain inconclusive due to various methodological issues. Here, we present results from an experiment in which we selected independently on the slope and the elevation of the allometric relationship between caudal-fin size and body size in male guppies (Poecilia reticulata). After three episodes of selection, the allometric elevation (i.e. intercept at constant slope) had diverged markedly between the lines selected to increase or decrease it, and showed a realized heritability of 50%. In contrast, the allometric slope remained unaffected by selection. These results suggest that the allometric elevation is more evolvable than the allometric slope, this latter representing a potential constraint on adaptive trait evolution. To our knowledge, this study is the first artificial-selection experiment that directly tests the evolvability of static allometric slopes.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Poecilia
/
Tamanho Corporal
/
Nadadeiras de Animais
Tipo de estudo:
Diagnostic_studies
Limite:
Animals
País/Região como assunto:
Caribe ingles
/
Trinidad y tobago
Idioma:
En
Revista:
J Evol Biol
Assunto da revista:
BIOLOGIA
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Noruega