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The analysis of the lower jaws of 265 wild boars, including 143 piglets and 122 yearlings, harvested in Zielonka Game Investigation Centre showed that farrowing took place most often in March (43.3%), February (23.8%), April (17.5%) and January (11.2%). Piglets were also born in May, June and July. The percentages for yearlings were a little different.
In order to investigate the most appropriate sampling to assess habitat effects on red deer, we analysed body mass, diastema length and length of the posterior part of the lower jaw of red deer females Cervus elaphus (Linnaeus 1758) in five study areas of the Ardennes (Belgium). Canonical discriminant analysis indicated that the female deer from the 5 study areas could be distinguished from each other on the basis of their body mass, diastema length and posterior length of the lower jaw. Body mass was the most correlated with the first canonical variable, while diastema length and posterior length of the lower jaw were less although significantly correlated. Age- -specific comparisons of means indicated that variations in body mass, diastema length and posterior length of the lower jaw of yearlings and > 4-year-old females were the most effective to separate the different populations and hence were good indices of respectively short and long term variations in environmental conditions. Univariate comparison of means suggested that posterior length of the lower jaw of yearlings could be a valuable alternative to body weight as an indice of habitat quality. The Von Bertalanffy growth equation with to fixed was used to assess the effect of habitat on asymptotic body mass and asymptotic jaw length and on the growth coefficients. The asymptotic values for body mass and jaw length were significantly higher where the habitat conditions appeared to be most favourable. In the poorest habitat, the growth of body mass and jaw length appeared slower, suggesting that female red deer, in this poorer habitat, could partially compensate their lower development as calves and yearlings by a longer growth period; however, only the growth coefficient of the posterior length of the lower jaw differed significantly from that of the best habitat.
The holotype of the brachyopoid temnospondyl Hadrokkosaurus bradyi, represented by a right lower jaw ramus, is re−examined based upon new data and revision of various morphological features. Additional fragmentary jaw material referred to this species is briefly described. Prominent features are a large postsymphyseal foramen that is anteriorly open, and prearticular and surangular buttresses for support of the articular. Brachyopoid characters include a long and robust postglenoid area formed by surangular and prearticular, anterior and posterior keels on at least some marginal dentary teeth, and subtriangular outline of the adductor fossa in dorsal view. Five features of the holotype ramus, long thought to be at odds with its brachyopoid or temnospondyl nature, are critically re−evaluated. A phylogenetic analysis of lower jaw characters in temnospondyls retrieves most of the clades found in more comprehensive data sets, but the statistical node support is low. Brachyopoids are monophyletic, with Hadrokkosaurus emerging as their most basal taxon.
Partially preserved temnospondyl mandibles from the Late Permian–Early Triassic Buena Vista Formation of Uruguay are referred to the basal stereospondyl taxon Mastodonsauridae. These represent the earliest known members of this group for South America. In most cases, this assignment was based on the characteristic morphology of the postglenoid (= postarticular) area of the lower jaw together with the presence of a hamate process. Comparisons with basal mastodonsaurids indicate that the Uruguayan specimens are phenetically similar to Gondwanan and Laurasian Early Triassic taxa, such as Watsonisuchus, Wetlugasarus, and Parotosuchus. Nevertherless, they display some characters which have not previously been described in Mesozoic temnospondyls. The Permo−Triassic Uruguayan mastodonsaurids support a Gondwanan origin for the group, an event which probably occurred sometime during the latest Permian.
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