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Complex ecological pressures affect the social dynamics of many primate species, but it is unclear how they affect primate speciation. Molecular tools are often used to answer questions about the evolutionary histories and social systems of primates. Mitochondrial DNA (mtDNA), in particular, is frequently used to answer many of these questions, but because it is passed from mothers to offspring it reveals only the histories of females. In many species, including chimpanzees, females generally disperse from their natal groups while males are philopatric, and thus differences in dispersal patterns likely leave different signatures in the genome. We previously analyzed samples from 187 unrelated male and female chimpanzees in Nigeria and Cameroon using 21 autosomal microsatellites and mtDNA sequences. Here, we examine the contributions of males and females in shaping the genetic history of these chimpanzees by genotyping a subset of 56 males at 12 Y-chromosome microsatellites. We found that Y-chromosome population structure differed from the results of analysis of mtDNA haplotypes. The results also revealed that males in rainforest habitats (Guinean and Congolian rainforests) are more closely related to one another than those inhabiting the savanna-woodland mosaic ecotone in central Cameroon. In contrast, the pattern of female relatedness did not differ across habitats. We hypothesize that these differences in population structure and patterns of relatedness among males in different habitat types may be due to differences in the community dynamics of chimpanzees in the ecotone vs. rainforests, and that these factors contribute to making Cameroon an engine of diversification for chimpanzees. Broadly, these results demonstrate the importance of habitat variation in shaping social systems, population genetics, and primate speciation.  相似文献   
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Many of the threats to bottlenose dolphins are anthropogenic factors including overfishing, high‐speed boats, chemical runoff, and noise pollution. Having a thorough understanding of the behavior and behavioral patterns of these animals can help with conservation plans to protect this species. This study examined the behavioral states and behavioral events of Atlantic bottlenose dolphins (Tursiops truncatus) in the Mississippi Sound. The behavioral states exhibited by dolphins within the Sound were found to vary by both season and time of day. Dolphins socialized more during the spring and spent more time feeding in the fall. Feeding was highest early in the morning and decreased throughout the day, while socializing occurred at low levels in the morning and increased in the early afternoon. Two distinct forms of social behavior and multiple feeding strategies were exhibited by dolphins within the Sound. Results suggest that certain percussive behavioral events may be used to communicate motivation during transitional behavioral states. These results demonstrate the need for a more complete understanding of dolphin behavior that will facilitate the conservation of this species.  相似文献   
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《Current biology : CB》2022,32(1):74-85.e4
Download : Download video (38MB)  相似文献   
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《Endocrine practice》2019,25(1):69-101
Abbreviations: A1C = hemoglobin A1C; AACE = American Association of Clinical Endocrinologists; ACCORD = Action to Control Cardiovascular Risk in Diabetes; ACCORD BP = Action to Control Cardiovascular Risk in Diabetes Blood Pressure; ACE = American College of Endocrinology; ACEI = angiotensin-converting enzyme inhibitor; AGI = alpha-glucosidase inhibitor; apo B = apolipoprotein B; ARB = angiotensin II receptor blocker; ASCVD = atherosclerotic cardiovascular disease; BAS = bile acid sequestrant; BMI = body mass index; BP = blood pressure; CCB = calcium channel blocker; CGM = continuous glucose monitoring; CHD = coronary heart disease; CKD = chronic kidney disease; DKA = diabetic ketoacidosis; DPP4 = dipeptidyl peptidase 4; eGFR = estimated glomerular filtration rate; EPA = eicosapentaenoic acid; ER = extended release; FDA = Food and Drug Administration; GLP1 = glucagon-like peptide 1; HDL-C = high-density-lipoprotein cholesterol; HeFH = heterozygous familial hypercholesterolemia; LDL-C = low-density-lipoprotein cholesterol; LDL-P = low-density-lipoprotein particle; Look AHEAD = Look Action for Health in Diabetes; NPH = neutral protamine Hagedorn; OSA = obstructive sleep apnea; PCSK9 = proprotein convertase subtilisin-kexin type 9 serine protease; RCT = randomized controlled trial; SU = sulfonylurea; SGLT2 = sodium-glucose cotransporter 2; SMBG = self-monitoring of blood glucose; T2D = type 2 diabetes; TZD = thiazolidinedione  相似文献   
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To improve the welfare of nonhuman animals under professional care, zoological institutions are continuously utilizing new methods to identify factors that lead to optimal welfare. Comparative methods have historically been used in the field of evolutionary biology but are increasingly being applied in the field of animal welfare. In the current study, data were obtained from direct behavioral observation and institutional records representing 80 individual animals from 34 different species of the order Carnivora. Data were examined to determine if a variety of natural history and animal management factors impacted the welfare of animals in zoological institutions. Output variables indicating welfare status included behavioral diversity, pacing, offspring production, and infant mortality. Results suggested that generalist species have higher behavioral diversity and offspring production in zoos compared with their specialist counterparts. In addition, increased minimum distance from the public decreased pacing and increased offspring production, while increased maximum distance from the public and large enclosure size decreased infant mortality. These results have implications for future exhibit design or renovation, as well as management practices and priorities for future research.  相似文献   
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