JS was supported by DFG grants (Ko1494/1-1, Ko1494/1-2).
A fecundity cost of (walking) mobility in an insect
Article first published online: 4 OCT 2012
© 2012 The Authors. Ecology and Evolution published by Blackwell Publishing Ltd.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Ecology and Evolution
Volume 2, Issue 11, pages 2788–2793, November 2012
How to Cite
Ecology and Evolution 2012; 2(11): 2788–2793
- Issue published online: 8 NOV 2012
- Article first published online: 4 OCT 2012
- Manuscript Accepted: 6 SEP 2012
- Manuscript Revised: 31 AUG 2012
- Manuscript Received: 18 MAY 2012
- DFG. Grant Numbers: Ko1494/1-1, Ko1494/1-2
- Cost of reproduction;
- movement ecology;
- oviposition rate
Evolutionary theory predicts trade-offs between fecundity and mobility, but there is substantial lack of empirical evidence if and how basic mobility relates to fitness costs. In a field experiment, we investigated fecundity costs of mobility in a non-migratory, wing-monomorphic grasshopper, Stenobothrus lineatus, and at the same time tested for possible effects of reproductive state (egg-load) on the mobility. For 10 days, body weight and activity radius of 60 females were recorded daily and oviposition events were inferred from abrupt weight losses. We found a strong and significant relationship between the individual mobility and the time between egg pods laid (interpod period). Individual egg-laying was reduced by a rate of 0.36 eggs per day with each meter increase in mean daily activity radius. The trade-off was not biased by the size of the females, that is, constitution did not positively influence both offspring number and mobility. Egg-load had no significant influence on the individual distances travelled. We could demonstrate that mobility – as induced and selected for by foraging, thermoregulation, predator escape, shelter seeking, and reproduction – can be directly paid off by fecundity. This direct consequence of mobility on individual fitness was detected for the first time in a walking insect.