Do placental species abort offspring? Testing an assumption of the Trexler–DeAngelis model
Article first published online: 11 DEC 2007
© 2007 The Authors
Volume 22, Issue 2, pages 323–331, April 2008
How to Cite
Banet, A. I. and Reznick, D. N. (2008), Do placental species abort offspring? Testing an assumption of the Trexler–DeAngelis model. Functional Ecology, 22: 323–331. doi: 10.1111/j.1365-2435.2007.01367.x
- Issue published online: 11 DEC 2007
- Article first published online: 11 DEC 2007
- Received 21 March 2007; accepted 30 October 2007Handling Editor: Gary Bortolotti
- offspring size;
- 1We investigate how resource level affects reproduction in matrotrophic (Poeciliopsis prolifica) and lecithotrophic (P. monacha) fishes.
- 2One of our goals was to test an assumption of the Trexler–DeAngelis model for the evolution of matrotrophy, which was that matrotrophic species can adjust litter size by aborting offspring in low food conditions. Our more general goal was to elucidate other differences between the reproductive modes.
- 3Both species have superfetation and c. 30-day development time. Females of each species were assigned to high or low food availability for 30 days, or one gestation period. Any young born during that time interval would have initiated development before the initiation of the experiment. If embryos are aborted, then this would be seen as a reduction in brood size in the low food treatment relative to the high food treatment within this period.
- 4Our results suggest P. monacha responds to low food by sacrificing reproduction to maintain lipids, while P. prolifica maintains reproduction at the expense of lipids. Neither species showed a significant reduction in offspring number over the course of the experiment, suggesting that these species do not abort offspring in low food conditions.