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Additional Tithonian and Berriasian ammonites from the Vaca Muerta Formation in Pampa Tril, Neuquén Basin, Argentina

Parent H., Schweigert G., Scherzinger A., Garrido A. C.

Volumina Jurassica

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2017

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Vol. 15, no 1

139--154

EN

The ammonite fauna of the Tithonian–Berriasian of the Vaca Muerta Formation in Pampa Tril has been recently described in detail. New important specimens and additional information are presented in this paper. The phyletic evolution of Choicensisphinctes, passing from C. platyconus to C. erinoides is confirmed, as well as the sexual dimorphic correspondence of this latter with C. mendozanus. A microconch of the genus Krantziceras is described for the first time. New specimens of Substeueroceras koeneni identical to the paralec¬totype, along with material already described from the koeneni Hz. (Koeneni Zone), point to the fixation of this horizon as the type horizon of the species. New specimens of Subthurmannia boissieri from the Damesi Zone match clearly the range of variation of this species in Spain, thus providing an element for time-correlation with the Tethyan standard scale. Additional material from the internispinosum alpha Hz. confirms the origin of W. internispinosum from C. proximus by the inception of an evolutionary innovation in the juvenile ontogeny.

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Local Ecotypes of Roe Deer Populations (Capreolus capreolus L.) in Relation to Morphometric Features and Fur Colouration in the Centre of the Iberian Peninsula

Horcajada-Sánchez F., Barja I.

Polish Journal of Ecology

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2016

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Vol. 64, nr 1

113--124

EN

The extent of the area occupied by populations of roe deer and the diversity of environments in which it lives, determine the existence of different local forms or ecotypes. In order to characterize the populations of the Guadarrama Mountains in the centre of the Iberian Peninsula we examined the morphology and fur colouration of 154 roe deer (Capreolus capreolus) based on their body size, age and sex. To determine the age of roe deer, we analyzed tooth cementum layers (incisor I1) to observe the growth lines. The remaining individual data (body size, sex and fur colouration) were obtained in the field, from animals hunted in the study area. In adult individuals, the average body weight in males was significantly higher than in females, being these weight ranges similar to those of the Iberian Peninsula and the rest of Europe. Body measurements were positively related to individuals age, but only significant differences in body girth were found between males and females. The analysis of fur colouration of dead specimens showed a high variability with four different ecotypes during the summer coat and not significant differences were found in the body size between individuals with different summer coats. The morphological parameters described in the roe deer of the Guadarrama Mountains do not correspond with the latitudinal gradient as it was indicated for other Spanish populations. However, the existence of Pleistocene refuges in the central mountains of the Iberian Peninsula seems to have provided a high variety of ecotypes in relation to fur colouration in the populations of Guadarrama Mountains.

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Effects of site conditions on sexual dimorphism and sex ratio in lowland populations of Aruncus sylvestris Kostel. (Rosaceae)

Marciniuk J., Marciniuk P., Rymuza K.

Polish Journal of Ecology

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2010

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Vol. 58, nr 2

249-257

EN

Studies on sexual dimorphism in reference to vegetative features and on the sex ratio in different environmental conditions were carried out in lowland populations of dioecious species Aruncus sylvestris. It was shown that female individuals of Aruncus sylvestris produced higher flowering shoots, longer inflorescences, more leaves and longer and broader leaves than the male ones. All listed differences were statistically significant. In populations of Aruncus sylvestris growing in optimum ecological conditions (fertile and wet soil, half-light) the sex ratio M/F is close to 1:1. Changes of ecological conditions along the gradient of fertility, habitat moisture (estimated by the types of phytocoenoses) and intensity of solar radiation caused marked drift of sex structure towards the male domination. Light intensity was the crucial factor for the sex ratio in studied populations. Populations growing in half-light showed sex ratio M/F [is approximately equal to] 1:1 irrespective of habitat. Those growing in shade and in full light showed significant shift to male dominance. The largest deviation from 1:1 sex ratio (M/F [is approximately equal to] 1.0:0.2) was observed in extremely unfavorable habitat conditions (full sun irradiance, dry soil, strong competition from Elymus repens (L.) Gould). Obtained results demonstrated that female individuals of Aruncus sylvestris had markedly higher habitat requirements compared with the male ones.