Discriminating the effects of phylogenetic hypothesis, tree resolution and clade age estimates on phylogenetic signal measurements.

Understanding how species traits evolved over time is the central question to comprehend assembly rules that govern the phylogenetic structure of communities. The measurement of phylogenetic signal (PS) in ecologically relevant traits is a first step to understand phylogenetically structured community patterns. The different methods available to estimate PS make it difficult to choose which is most appropriate. Furthermore, alternative phylogenetic tree hypotheses, node resolution and clade age estimates might influence PS measurements. In this study, we evaluated to what extent these parameters affect different methods of PS analysis, and discuss advantages and disadvantages when selecting which method to use. We measured fruit/seed traits and flowering/fruiting phenology of endozoochoric species occurring in Southern Brazilian Araucaria forests and evaluated their PS using Mantel regressions, phylogenetic eigenvector regressions (PVR) and K statistic. Mantel regressions always gave less significant results compared to PVR and K statistic in all combinations of phylogenetic trees constructed. Moreover, a better phylogenetic resolution affected PS, independently of the method used to estimate it. Morphological seed traits tended to show higher PS than diaspores traits, while PS in flowering/fruiting phenology depended mostly on the method used to estimate it. This study demonstrates that different PS estimates are obtained depending on the chosen method and the phylogenetic tree resolution. This finding has implications for inferences on phylogenetic niche conservatism or ecological processes determining phylogenetic community structure.

[Who requests voluntary interruption of pregnancy?]. / Qui demande l'IVG?

PIP: The sense that abortion is the last resort for women placed in a distress situation by the continuation of the pregnancy should be preserved. No woman requesting abortion regards it as trivial, and postabortal depressions are more common than the banalization of the procedure might imply. Reasons for terminating the pregnancy are usually among the following: breakup of the couple, a recent loss, advanced age of existing children, emigration, or material difficulty. The psychological situation of pregnant adolescents is confused and sad, mixing the normal difficulties of adolescents with the affective problems of pregnancy and perhaps family problems as well. Pregnancy to an adolescent can symbolically represent a lack, a competition, or a selfpunishment; it can function as a proof of femininity, or a means of informing the parents of the girl's sex life. Pregnancy and abortion are experienced differently by adult women, who at a certain age feel a strong drive to realize the wish for maternity. Nevertheless, some women suffer a permanent conflict between the desire to have and the desire not to have children. Adult women may desire pregnancy, even accidental pregnancy, to prove their fertility, relive their own childhood, reassure themselves about menopause, fill a lack, or for numerous other reasons apart from wanting a child. Voluntary abortion can be defined as a strong unconscious desire for pregnancy tied to a conscious rejection of maternity. Interviews with women requesting abortions disclose the numerous conflicts that may exist with a maternal image, with the woman's own body, in the case of a recent loss, or at the breakup of a marriage. Studies have shown that the ambience in which the abortion is performed is of overwhelming importance for the later attitude of the woman; personnel involved should avoid adding to the trauma already experienced by the woman by making her feel guilty.^ieng