Format

Send to

Choose Destination
See comment in PubMed Commons below
Am Nat. 2009 Jun;173(6):819-30. doi: 10.1086/598492.

Timing of flowering: opposed selection on different fitness components and trait covariation.

Author information

1
Department of Botany, Stockholm University, SE-106 91 Stockholm, Sweden. ehrlen@botan.su.se

Abstract

The timing of reproduction influences how organisms interact with the environment and can have important fitness effects. In plants, the evolution of flowering phenology is often interpreted as the response to selection from mutualists, although antagonistic interactions may also be important. We examined direct and indirect phenotypic selection on the start of flowering via mutualistic and antagonistic interactions in the perennial herb Lathyrus vernus over 7 years. Flowering start influenced seed set, predispersal seed predation, and risk of grazing. These effects were in opposed directions and partly influenced different components of fitness. Combining information about effects on fitness components with information about links between fitness components and average lifetime fitness, in terms of population growth rate, showed that earlier flowering was associated with higher lifetime fitness in all years. These relationships were, however, mediated largely by variation in flower number, and direct selection on first flowering date was more variable among years. We conclude that long-term studies correcting for indirect selection and environmental covariance are needed to understand selection on reproductive phenology and that demographic approaches are necessary to assess selection mediated by several agents and influencing several components of fitness.

PMID:
19335224
DOI:
10.1086/598492
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for University of Chicago Press
    Loading ...
    Support Center