Abstract
A female's reproductive output (size and number of offspring) may say little about her reproductive success; the 'quality' of her progeny and the time that they are produced may be more important in this respect. We marked and released 1224 hatchling water pythons (Liasis fuscus) from 116 clutches of laboratory-incubated eggs, in a study site in tropical Australia. Clutches varied widely in the number of eggs, mean offspring sizes, the proportion of eggs that hatched, and recapture rates of offspring. Clutch size was not significantly correlated with the number of recaptured hatchlings in either year, nor was mean offspring size related to recapture probability. Instead, offspring recapture rates varied as a function of the time of hatching. Recapture rates were higher for hatchlings released in a year with high prey availability than in a year with few prey. In addition, recapture rates were higher for earlier-hatching clutches in the year with few prey. The other significant effect on recapture rates involved offspring viability: some clutches had a much higher proportion of surviving offspring than did others, and recapture rates were higher from clutches with higher hatching success (i.e. proportion of eggs hatching). Hence, the usual measures of reproductive output (clutch size and offspring size) offer only a poor index of a female's reproductive success in this system.
Full Text
The Full Text of this article is available as a PDF (132.7 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- McNamara J. M., Houston A. I. State-dependent life histories. Nature. 1996 Mar 21;380(6571):215–221. doi: 10.1038/380215a0. [DOI] [PubMed] [Google Scholar]
- Shine R. Propagule size and parental care: the "safe harbor" hypothesis. J Theor Biol. 1978 Dec 21;75(4):417–424. doi: 10.1016/0022-5193(78)90353-3. [DOI] [PubMed] [Google Scholar]
- Sinervo B., Huey R. B. Allometric engineering: an experimental test of the causes of interpopulational differences in performance. Science. 1990 Jun 1;248(4959):1106–1109. doi: 10.1126/science.248.4959.1106. [DOI] [PubMed] [Google Scholar]
- Sinervo B., Zamudio K., Doughty P., Huey R. B. Allometric engineering: a causal analysis of natural selection on offspring size. Science. 1992 Dec 18;258(5090):1927–1930. doi: 10.1126/science.258.5090.1927. [DOI] [PubMed] [Google Scholar]
- Stearns S. C. Life-history tactics: a review of the ideas. Q Rev Biol. 1976 Mar;51(1):3–47. doi: 10.1086/409052. [DOI] [PubMed] [Google Scholar]