Reproductive ecology of dipsadine snakes, with emphasis on South American species

A relatively large amount of variation occurs in the reproductive ecology of tropical snakes, and this variation is generally regarded as being a consequence of seasonality in climate and prey availability. In some groups, even closely related species may differ in their reproductive ecology; however, in others it seems to be very conservative. Here we explore whether characters related to reproduction are phylogenetically constrained in a monophyletic group of snakes, the subfamily Dipsadinae, which ranges from Mexico to southern South America. We provide original data on reproduction for Leptodeira annulata, Imantodes cenchoa, and three species of Sibynomorphus from southern, southeastern and central Brazil, and data from literature for other species and populations of dipsadines. Follicular cycles were seasonal in Atractus reticulatus, Dipsa, albifrons, Hypsiglena torquata, Leptodeira maculata, L. punctata, Sibynomorphus spp. and Sibon sanniola from areas where climate is seasonal. In contrast, extended or continuous follicular cycles were recorded in Dipsas catesbyi, D. neivai, Imantodes cenchoa, Leptodeira annulata, and Ninia maculata from areas with seasonal and aseasonal climates. Testicular cycles also varied from seasonal (in H. torquiata) to continuous (in Dipsa,5 spp., Leptodeira annulata, L. maculata, N. maculata, and Sibynomorphus spp.). Most dipsadines are small (less than 500 rum SVL), and females attain sexual maturity with similar relative body size than males. Sexual dimorphism occurred in terms of SVL and tail length in most species, and clutch size tended to be small (less than five eggs). Combat behavior occurs in Imantodes cenchoa, which did not show sexual size dimorphism. Reproductive timing, for both females and males, varied among species but in general there were no differences between the tribes of Dipsadinae in most of the reproductive characteristics, such as mean body size, relative size at sexual maturity, sexual size and tail dimorphism, duration of vitellogenesis or egg-carrying in oviducts.

Some reflections on South-East Asian export industrialization

Includes bibliography

Committee on South-South cooperation: provisional agenda

Includes bibliography

Committee on South-South cooperation: annotated provisional agenda

Includes bibliography

Committee on South-South cooperation: provisional agenda

Includes bibliography

Committee on South-South cooperation: annotated provisional agenda

Includes bibliography

Committee on South-South Cooperation: provisional agenda, 29 August 2012

Spanish version available

Committee on South-South Cooperation: annotated provisional agenda, 29 August 2012

Spanish version available

The impact of external sector developments on Caribbean economic performance, 1983-1988

Includes bibliography

Report of the first meeting of the Presiding Officers of the Committee on South-South Cooperation

Spanish version available

Report of the second meeting of the Presiding Officers of the Committee on South-South Cooperation

Spanish version available

The tourist cruise industry and its impact on South America

The global tourist cruise industry has been experiencing sustained growth for quite some time; the industry's future prospects are promising, due to good profitability and a reduction in costs achieved thanks to use of ever larger ships, which are making this new form of tourism accessible to more and more people.South American destinations have been visited by a wide range of cruise operators, reflecting the expansion of this industry worldwide; it is necessary that players in the industry take advantage of this opportunity to provide services that employ substantial numbers of people and develop port facilities in order to meet the requirements of ships and tourists alike, thereby heading off competition from other routes.