A population of sexual Daphnia pulex resists invasion by asexual clones.
Proc Biol Sci
; 281(1788): 20140564, 2014 Aug 07.
Article
em En
| MEDLINE
| ID: mdl-24943366
ABSTRACT
Asexual reproduction avoids the costs associated with sex, predicting that invading asexual clones can quickly replace sexual populations. Daphnia pulex populations in the Great Lakes area are predominately asexual, but the elimination of sexual populations by invading clones is poorly understood. Asexual clones were detected at low frequency in one rare sexual population in 1995, with some increase in frequency during 2003 and 2004. However, these clones remained at low frequency during further yearly sampling (2005-2013) with no evidence that the resident sexual population was in danger of elimination. There was evidence for hybridization between rare males produced by asexual clones and sexual females with the potential to produce new asexual genotypes and spread the genetic factors for asexuality. In a short-term laboratory competition experiment, the two most common asexual clones did not increase in frequency relative to a genetically diverse sexual population due in part to a greater investment in diapausing eggs that trades-off current population growth for increased contribution to the egg bank. Our results suggest that a successful invasion can be prolonged, requiring a combination of clonal genotypes with high fitness, persistence of clones in the egg bank and negative factors affecting the sexual population such as inbreeding depression resulting from population bottlenecks.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Reprodução Assexuada
/
Daphnia
/
Genótipo
Tipo de estudo:
Prognostic_studies
Limite:
Animals
País/Região como assunto:
America do norte
Idioma:
En
Revista:
Proc Biol Sci
Assunto da revista:
BIOLOGIA
Ano de publicação:
2014
Tipo de documento:
Article