Inter-class competition in stage-structured populations: effects of adult density on life-history traits of adult and juvenile common lizards.

Details

Serval ID
serval:BIB_1175C0480B6A
Type
Article: article from journal or magazin.
Collection
Publications
Title
Inter-class competition in stage-structured populations: effects of adult density on life-history traits of adult and juvenile common lizards.
Journal
Oecologia
Author(s)
San-Jose L.M., Peñalver-Alcázar M., Huyghe K., Breedveld M.C., Fitze P.S.
ISSN
1432-1939 (Electronic)
ISSN-L
0029-8549
Publication state
Published
Issued date
12/2016
Peer-reviewed
Oui
Volume
182
Number
4
Pages
1063-1074
Language
english
Notes
Publication types: Journal Article
Publication Status: ppublish
Abstract
Ecological and evolutionary processes in natural populations are largely influenced by the population's stage-structure. Commonly, different classes have different competitive abilities, e.g., due to differences in body size, suggesting that inter-class competition may be important and largely asymmetric. However, experimental evidence states that inter-class competition, which is important, is rare and restricted to marine fish. Here, we manipulated the adult density in six semi-natural populations of the European common lizard, Zootoca vivipara, while holding juvenile density constant. Adult density affected juveniles, but not adults, in line with inter-class competition. High adult density led to lower juvenile survival and growth before hibernation. In contrast, juvenile survival after hibernation was higher in populations with high adult density, pointing to relaxed inter-class competition. As a result, annual survival was not affected by adult density, showing that differences in pre- and post-hibernation survival balanced each other out. The intensity of inter-class competition affected reproduction, performance, and body size in juveniles. Path analyses unravelled direct treatment effects on early growth (pre-hibernation) and no direct treatment effects on the parameters measured after hibernation. This points to allometry of treatment-induced differences in early growth, and it suggests that inter-class competition mainly affects the early growth of the competitively inferior class and thereby their future performance and reproduction. These results are in contrast with previous findings and, together with results in marine fish, suggest that the strength and direction of density dependence may depend on the degree of inter-class competition, and thus on the availability of resources used by the competing classes.

Keywords
Animals, Body Size, Lizards, Population Density, Population Dynamics, Reproduction
Pubmed
Create date
16/09/2016 9:50
Last modification date
20/08/2019 13:39
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