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Nursing and weaning are behaviors that are central to the growth of offspring and success of mammal populations. The duration of nursing and timing of weaning are essential elements of a species' life history, but they are also somewhat plastic; weaning age increases during intervals of drought or other dietary stress. Thus, weaning age provides a proxy for nutritional stress in an extinct population, provided there is a way to determine weaning age for long-dead individuals. In growth records of proboscidean tusks, stable isotope compositions have been used to investigate nursing and weaning, but a taxon-specific framework for interpreting isotope data has been lacking. Here, we present results of a longitudinal study of stable isotopes in a nursing dam-calf pair of captive African elephants. The data include behavioral observations and hair growth rates, as well as stable isotope ratios in elephant feed and drinking water, in plasma and milk from the dam, and in tail hair from both individuals. Serial changes in the stable isotope ratios of nitrogen (δ15N), carbon (δ13C), oxygen (δ18O), and hydrogen (δ2H) reflect the transitions from placental nutrition in utero to exclusive nursing immediately after birth, and then to final weaning when the calf was six years old. Three of the four isotope systems reveal enrichment in the calf with respect to the dam prior to parturition and all show this relative enrichment during early nursing. At the end of nursing, final weaning was marked by changes in two of the systems: the convergence of dam and calf δ13C records and the abrupt onset of relative depletion in calf 15N following a year of elevated δ15N in both individuals. These patterns provide criteria for recognizing records of nursing and weaning contained in fossil tusks, providing grounds for assessing stress in prehistoric populations.

Natural resource rules exist to manage resources and the people that interact with them. These rules often fail because people do not comply with them. Decisions to comply with natural resource rules often are based on attitudes about legitimacy of rules and the perceived risks of breaking rules. Trust in agencies promulgating rules in part may determine perceptions of legitimacy of the rule, and in turn depends on individuals’ trust in different agency actors. The purpose of this research was to explore the relationship between fishing rule noncompliance and trust in scientists, a key group within management agencies. We interviewed 41 individuals in one rural fishing community in the Brazilian Pantanal from April to August, 2016, to assess (1) noncompliance rates, (2) noncompliance-related attitudes, and (3) the relationship between trust in scientists and noncompliance decisions in the region. We found that among study participants, noncompliance was common and overt. Trust in scientists performing research in the region was the best predictor of noncompliance rate with a fishing rule (nonparametric rank correlation ρ = −0.717; Probit model pseudo-R2 = 0.241). Baseline data from this research may help inform future interventions to minimize IUU fishing and protect the Pantanal fishery. Although our results are specific to one community in the Pantanal, trust in scientists is potentially an important factor for compliance decisions in similar situations around the world. These results build not only on compliance theory but also speak to the important role that many scientists play in the geographic areas in which they conduct their research.

A partial carcass of an adult woolly mammoth (Mammuthus primigenius) found in 2012 on Maly Lyakhovsky Island presents a new opportunity to retrieve associated anatomical, morphological, and life history data on this important component of Pleistocene biotas. In addition, we address hematological, histological, and microbiological issues that relate directly to quality of preservation. Recovered by staff from North-Eastern Federal University in Yakutsk, this individual is a relatively old female preserving soft tissue of the anteroventral portion of the head, most of both fore-quarters, and the ventral aspect of much of the rest of the body. Both tusks were recovered and subjected to computed tomographic analysis in which annual dentin increments were revealed as cycles of variation in X-ray attenuation. Measurements of annual increment areas (in longitudinal section) display a pulsed pattern of tusk growth showing cycles of growth rate variation over periods of 3-5 years. These intervals are interpreted as calving cycles reflecting regular shifts in calcium and phosphate demand for tusk growth vs. fetal ossification and lactation. Brown liquid associated with the frozen carcass turned out to include remains of hemolyzed blood, and blood samples examined microscopically included white blood cells with preserved nuclei. Muscle tissue from the trunk was unusually well preserved, even at the histological level. Intestinal contents and tissue samples were investigated microbiologically, and several strains of lacticacid bacteria (e.g., Enterococcus faecium, Enterococcus hirae) that are widely distributed as commensal organisms in the intestines of herbivores were isolated. (C) 2017 Elsevier Ltd and INQUA. All rights reserved.

Two female woolly mammoth neonates from permafrost in the Siberian Arctic are the most complete mammoth specimens known. Lyuba, found on the Yamal Peninsula, and Khroma, from northernmost Yakutia, died at ages of approximately one and two months, respectively. Both specimens were CT-scanned, yielding detailed information on the stage of development of their dentition and skeleton and insight into conditions associated with death. Both mammoths died after aspirating mud. Khroma's body was frozen soon after death, leaving her tissues in excellent condition, whereas Lyuba's body underwent postmortem changes that resulted in authigenic formation of nodules of the mineral vivianite associated with her cranium and within diaphyses of long bones. CT data provide the only comprehensive approach to mapping vivianite distribution. Three-dimensional modeling and measurement of segmented long bones permits comparison between these individuals and with previously recovered specimens. CT scans of long bones and foot bones show developmental features such as density gradients that reveal ossification centers. The braincase of Khroma was segmented to show the approximate morphology of the brain; its volume is slightly less (∼2,300 cm3) than that of neonate elephants (∼2,500 cm3). Lyuba's premaxillae are more gracile than those of Khroma, possibly a result of temporal and/or geographic variation but probably also reflective of their age difference. Segmentation of CT data and 3-D modeling software were used to produce models of teeth that were too complex for traditional molding and casting techniques.