Maternal investment and sex-allocation in the Galapagos fur seal, Arctocephalus galapagoensis

Trillmich F (1986)
Behavioral Ecology and Sociobiology 19(3): 157-164.

Download
OA
Zeitschriftenaufsatz | Veröffentlicht | Englisch
Abstract / Bemerkung
Maternal investment and sex-allocation were measured in a large, sexually dimorphic mammal, the Galapagos fur seal (Arctocephalus galapagoensis). The sex ratio at birth was 1.06. Males were always heavier than females and, at least initially, grew faster. Growth was variable from year to year suggesting energetic constraints on maternal investment. Sucking time conrrelated with milk intake. Mothers suckled yearling and 2-year-old sons more than daughters of the same age. Age at weaning appeared to be the same in both sexes or even slightly greater in males. No sex differences was found in mortality prior to weaning or in post-weaning dispersal. Birth rates of females with yearlings or 2-year-olds were significantly lower than those of females with no dependent young. Mothers invested more in sons than in daughters until weaning. It is unlikely that higher post-weaning investment in daughters balances the higher pre-weaning investment in sons. Data on sex ratio at birth, different growth rates, and weaning age of the sexes are typical of otariid seals as a group. The results of this study fit Maynard Smith's (1980) model of the evolution of sex allocation better than Fisher's (1930).
Erscheinungsjahr
Zeitschriftentitel
Behavioral Ecology and Sociobiology
Band
19
Zeitschriftennummer
3
Seite
157-164
ISSN
PUB-ID

Zitieren

Trillmich F. Maternal investment and sex-allocation in the Galapagos fur seal, Arctocephalus galapagoensis. Behavioral Ecology and Sociobiology. 1986;19(3):157-164.
Trillmich, F. (1986). Maternal investment and sex-allocation in the Galapagos fur seal, Arctocephalus galapagoensis. Behavioral Ecology and Sociobiology, 19(3), 157-164. doi:10.1007/BF00300855
Trillmich, F. (1986). Maternal investment and sex-allocation in the Galapagos fur seal, Arctocephalus galapagoensis. Behavioral Ecology and Sociobiology 19, 157-164.
Trillmich, F., 1986. Maternal investment and sex-allocation in the Galapagos fur seal, Arctocephalus galapagoensis. Behavioral Ecology and Sociobiology, 19(3), p 157-164.
F. Trillmich, “Maternal investment and sex-allocation in the Galapagos fur seal, Arctocephalus galapagoensis”, Behavioral Ecology and Sociobiology, vol. 19, 1986, pp. 157-164.
Trillmich, F.: Maternal investment and sex-allocation in the Galapagos fur seal, Arctocephalus galapagoensis. Behavioral Ecology and Sociobiology. 19, 157-164 (1986).
Trillmich, Fritz. “Maternal investment and sex-allocation in the Galapagos fur seal, Arctocephalus galapagoensis”. Behavioral Ecology and Sociobiology 19.3 (1986): 157-164.
Volltext(e)
Access Level
OA Open Access
Zuletzt Hochgeladen
1970-01-01T00:00:00Z

Export

Markieren/ Markierung löschen
Markierte Publikationen

Open Data PUB

Suchen in

Google Scholar