bluuebunny/crossref_metadata_2025_split huggingface dataset:
Location effects of social partner on experimental foraging in the squirrel monkey
Authors: Andrews Michael W. , Rosenblum Leonard A. 
Published: June 2005

AbstractThe effect of social context on experimental foraging in squirrel monkeys (Saimiri sciureus) was investigated. The 12 subjects comprised six pairs in which strong social preference and attraction had been demonstrated during observations of a stable group. Individuals were first trained to discriminate spatially separated rich and poor foraging bins containing 75% and 25% of the food items, respectively, with their partners restrained equidistant from the two bins. The monkeys invested an average of 75.5% of their foraging time in the rich bin. Each individual was then tested with its partner restrained in different locations relative to the bins to determine the effect of partner proximity on foraging patterns. Foraging efficiency at the start of a session was enhanced when the partner was restrained adjacent to the rich bin compared to restraint away from this bin. Over an entire foraging session, however, all conditions providing partner accessibility were similar in yielding enhanced foraging efficiency compared to partner absence. Little time was spent in close physical proximity to the partner under any condition. It is suggested that accessibility of the social partner, rather than close physical proximity, has an important influence on the foraging squirrel monkey. © 1995 Wiley‐Liss, Inc.
Behavioral characterization of sleep in stumptail macaques (Macaca arctoides) in exterior captivity by means of high‐sensitivity videorecording
Authors: Muñoz‐Delgado Jairo , Luna‐Villegas Gustavo , Mondragón‐CeballoS Ricardo , Fernández‐Guardiola Augusto 
Published: June 2005

AbstractThere are reasons to consider incomplete the description of sleep in many non‐human primate species. Recording animals by highly sensitive videos to obtain detailed descriptions of nighttime behavior and evidence of muscle activity while in a resting posture, seems a promising approach to the non‐invasive study of sleep in non‐human primates. The present work describes the use of ultrasensitive videocameras to record and analyze spontaneous nighttime behaviors in captive non‐human primates. Its main purpose is to emphasize the utility of videorecordings to analyze nighttime behavior. A heterosexual group of nine stumptail macaques (M. arctoides) was studied. It was possible to identify resting postures: immobility or lying on the floor as well as sleep movements and behavioral signs of sleep. This procedure permits recognition of each animal individually and the data suggest that videorecordings, among other techniques available, may be a useful, non‐invasive method to study sleep. © 1995 Wiley‐Liss, Inc.
Correlates of molt in golden lion tamarins (Leontopithecus rosalia)
Authors: Dietz James M. , Baker Andrew J. , Allendorf Terilyn D. 
Published: June 2005

AbstractIn this paper we describe the timing and correlates of molt for a native population of golden lion tamarins (Leontopithecus rosalia). We conducted 820 examinations of 267 adult tamarins over a 7.75 year period to determine the annual molting cycle in this population. Dorsal molt was an annual event for most individuals in the study population; however, 10% of sampled individuals apparently molted twice in a 12 month period. Duration of molt was estimated at 5–6 weeks. The proportion of samples in which tamarins were in molt was significantly greater during the wet season than the dry season and positively correlated with mean monthly precipitation and minimum temperature but not tamarin births, suggesting an environmental component to timing of molt. We found no sex differences in the occurrence of molt during wet or dry seasons. However, the relative frequency of samples in molt was significantly less for gravid females than for nongravid females. In four polygynous groups, socially dominant females gave birth before subordinate females, and younger reproductive females completed molt before older reproductive females. © 1995 Wiley‐Liss, Inc.
Fecal steroid analysis of ovarian cycles in free‐ranging baboons
Authors: Stavisky Ronda , Russell Elizabeth , Stallings Joy , Smith E. O. , Worthman Carol , Whitten Patricia L. 
Published: June 2005

AbstractThis paper reports field and laboratory tests of serial sampling, solid phase extraction, and microradioimmunoassay methods for the collection, preservation, and analysis of fecal steroids. The field study was conducted in a troop of 87 yellow baboons (Papio cynocephalus) in the Tana River Primate Reserve, Kenya. Serial samples of four focal females and opportunistic sampling of 18 additional females over 22 days of sampling yielded a total of 62 samples, X = 3.1 ± 0.4/day, demonstrating the feasibility of regular field collection and extraction. Estradiol and progesterone concentrations in the field‐extracted samples exhibited high recovery and statistically significant correlations (P < 0.05) with concentrations in the lab‐extracted samples, suggesting that solid phase extraction could provide a useful alternative to freezing in sites where electricity or liquid nitrogen is not available. Tests of microradioimmunoassays demonstrated that these assays were sensitive, accurate, and precise when applied to the assay of fecal extracts, providing estimates of ovarian steroids that varied significantly with reproductive state. The demonstration that testosterone could be accurately and reliably assayed in fecal extracts suggests that these techniques also could be applied to the study of male reproductive function. Parallels between fecal profiles of cycling and pregnant baboons with patterns reported for serum steroids in baboons suggest that fecal steroids might be useful in distinguishing amenorrhea from early pregnancy in free‐ranging baboons as well as in species lacking external indices of reproductive state. © 1995 Wiley‐Liss, Inc.
Sleeping habits of brown capuchin monkeys (Cebus apella) in French Guiana
Authors: Zhang Shu‐Yi 
Published: June 2005

AbstractSleeping habits of brown capuchin monkeys (Cebus apella) were studied during 19 months in French Guiana. High forest, covering 89% of the 355 ha home range of the studied group, was the only vegetal formation used for sleeping. The sleeping‐focused area of 94 ha, located in the center of the home range, was more frequently used for daily activities. Twenty‐six percent of the individuals spent the night in patawa palms, which account for only 0.62% of the plants of diameter at breast height ≥ 16.1 in the 43 1 ha quadrats used for sleeping. Three major factors seem to affect the preference of patawas as sleeping trees: security, comfort, and social contact. © 1995 Wiley‐Liss, Inc.
Development and social dominance among group‐living primates
Authors: Pereira Michael E. 
Published: June 2005

AbstractOrganisms are integrated systems whose physical and behavioral components codevelop and coevolve. Ontogenetic requirements in one domain are satisfied in part by prior or concurrent developments in another. This work explores how characteristic growth patterns in two primate groups interact with ecological, social, and other life‐history constraints to promote the development of particular systems of agonistic relationship. First, the markedly size‐dimorphic savanna baboons are contrasted with relatively nondimorphic macaques, where the pubertal growth capacity of males, relative to that of females, is comparatively modest. In baboons and other dimorphic Papionines, maturing males can be expected to invest more heavily in successful feeding competition, and known variation in the ontogeny of male‐female dominance relations is well explained by this prediction. Data from five of the best‐known species, for example, suggest that the female inclination to promote offspring dominaxice over male peers before puberty diminishes with increases in relative male size and growth potential at puberty. Potential mechanisms for the development of this pattern are discussed. Next, ontogenies are considered for ringtailed lemurs, a highly social, monomorphic prosimian primate in which seasonal scheduling of growth causes a large proportion of adult size to be achieved before weaning. In this species, daughters invariably develop strong alliances with their mothers, and pubertal females must overturn adults in dominance to remain in large natal groups. Despite life‐history parallels between ringtails and the focal Papionines, the lemurs do not collaborate agonistically in ways that ensure matrilineal “inheritance” of dominance status, as seen in the monkeys. Body weight and individual fighting ability appear to determine dominance relations among infants, and asymmetries established before weaning typically remain stable until sexual maturation. Anatomical and behavioral data suggest that low visual acuity prevents ringtailed lemurs from developing a system of agonistic intervention that could stabilize adult dominance hierarchies and mediate rank inheritance. In any case, failure to promote the dominance of close kin is argued to have influenced life‐history evolution in ringtailed lemurs extensively, including aspects of growth, reproductive biology, and social structure. These analyses identify foci for future research and illustrate the importance of bidirectional effects and feedback in the development and evolution of primate life histories and behavior. © 1995 Wiley‐Liss, Inc.
Neonatal weight in gibbons (Hylobates spp.)
Authors: Geissmann Thomas , Orgeldinger Mathias 
Published: June 2005

AbstractNeonatal and birth weights of gibbons have mostly been reported for single individuals, and larger samples (n = 2–8) have apparently been published for only two species of gibbons (Hylobates lar and H. syndactylus). In addition, a critical examination of the few published neonatal weights of gibbons shows that several of them should not be used. Neonatal weights are here defined as weights taken on infants up to seven days old, whereas birth weights include only those taken on the day of birth. This paper presents neonatal weights for six representative species of gibbons (H. lar, H. leucogenys, H. moloch, H. muelleri, H. pileatus, H. syndactylus) and some of their hybrids. Most of our data stem from surviving animals that were subsequently hand‐reared and include 80 infants, thus making the previously available dataset 5 times larger. Our neonatal weights fall roughly into three different classes: neonates of the lar group (about 390 g, n = 27), the concolor group (about 510 g, n = 7), and the siamang (about 540 g, n = 46). This grouping corresponds not only to taxonomic units within the hylobatids, but also to grouping of gibbons by adult body weight. No weight difference between males and females is evident in our sample, and hybrids of the lar group do not appear to differ in weight from pure species. True birth weights (i.e., weights recorded on the day of birth) are available for only a few individuals. These weights are, on average, 7% higher than neonatal weights, but the difference is not statistically significant. Additional samples of neonatal weights suggest that infants that die on the day of birth weigh, on average, 17% less, twins weigh 29% less, and infants born by Cesarean section weigh 19% more than our reference sample of neonates. © 1995 Wiley‐Liss, Inc.
Drinking tools of wild chimpanzees at Bossou
Authors: Sugiyama Yukimaru 
Published: June 2005

AbstractUse of drinking tools by wild chimpanzees (Pan troglodytes) and the context in which the tools were used were studied at Bossou, Republic of Guinea, West Africa. During the middle to late dry season and early wet season liquids are available occasionally in the holes of trees. Chimpanzees drank water or sap using a leaf (or fiber) as a sponge or spoon. When the chimpanzees were on the ground, they tended to use one of a few kinds of soft, hairless leaves, if they were available nearby. Females, particularly juveniles and adolescents, were thought to be the main users of the drinking tool. In a few episodes, a tool set was used to procure liquid. Once a chimpanzee used a stick to push a leaf sponge into a water hole and to pull it out from the hole. In addition, three chimpanzees used a pestle to squeeze sap from an oil‐palm tree before using a fiber sponge. © 1995 Wiley‐Liss, Inc.
Urine and fecal sample collection on filter paper for ovarian hormone evaluations
Authors: Shideler S. E. , Munro C. J. , Johl H. K. , Taylor H. W. , Lasley B. L. 
Published: June 2005

AbstractA practical method for collecting, storing, and transporting liquid biological samples in a dry state for subsequent hormone metabolite analyses is presented. This method employs the use of ordinary filter paper strips that imbibe liquid samples. Samples taken up by the filter paper were allowed to dry and were retained at ambient conditions in capped vials for up to 5 years prior to analysis. Examples presented in the present report include urine samples from human and nonhuman primates as well as solubilized fecal samples from nonhuman primates. Hormone metabolite analysis of the paper‐stored samples provided data that were comparable to the results obtained from analyses of the original liquid samples. One year of storage had no effect on hormone concentration. Five years of storage resulted in concentrations that were quantitatively less but qualitatively similar to the concentrations obtained by direct analysis of the initial samples. These data demonstrate the versatility and reliability of paper as a matrix for biological samples that may provide a more convenient approach for collecting and transporting samples collected in the field. © 1995 Wiley‐Liss, Inc.
Homo erectus: Ancestor or evolutionary side branch?
Authors: Rightmire G. Philip 
Published: June 2005

AbstractControversies in paleoanthropology wax and wane, but substantial interest is currently focused on Homo erectus. This species has traditionally been regarded as a member in good standing of the human family, where it is placed as an evolutionary intermediate between earlier Homo habilis and later Homo sapiens. Recently, however, some workers have questioned whether the species exists at all. If its populations have been transformed slowly toward the modern condition, and if continuity with living people can be demonstrated in many geographic regions, then any separation of Homo erectus from Homo sapiens must be largely arbitrary. In that case, only one species should be recognized and this slowly changing lineage would have to be called Homo sapiens. Other paleontologists adopt a different view, arguing that Homo erectus is not only anatomically distinctive but also restricted in its geographic distribution. They claim that the fossils from Java and China are so specialized in appearance that they cannot lie in the mainstream of human evolution. Homo erectus, strictly defined as limited to the Far East, probably went extinct without issue. If so, more modern populations must have evolved from another source, perhaps one outside of Asia altogether.
VNTRs in review
Authors: Harding Rosalind M. 
Published: June 2005

AbstractIn the last decade the study of human genetic variation has made a quantum leap from the analysis of protein and antigen intermediaries to the investigation of DNA itself.1 The DNA double helix codes genetic information as a sequence of four different nucleotides: adenine (A), guanine (G), cytosine (C), and thymine (T). Nucleotides are nitrogenous bases that bind the complementary strands of the double helix, giving rise to the use of base pairs (bp) as a unit of DNA length. So far so good. Within the human genome there are DNA sequences that do not code for proteins and that consist of short runs of nucleotides, say GTGGACAGG, repeated in tandem hundreds, or even thousands of times. This particular sequence, known as MS1 for minisatellite 1, is found on human chromosome 1 at a locus called D1S7. Although it is old news that there are a lot of repetitive DNAs in the human genome, it is new and very interesting to find that many repetitive DNA loci have arrays of different numbers of repeats in different individuals. These loci are referred to as VNTRs, shorthand for “variable numbers of tandem repeats” or, more flippantly for “very nasty types of repeat.” The finding of hundreds of VNTR loci distributed across all chromosomes exposes a richness of genetic diversity for anthropologists studying human evolutionary history.
Intentional deception in primates
Authors: de Waal Frans B. M. 
Published: June 2005

AbstractDeception can be defined as the projection, to one's own advantage, of an inaccurate or false image of knowledge, intentions, or motivations. A great many scientists have reported the use of deception by nonhuman primates. Their accounts have been based on observations of primates in close contact with people, in captive groups, and in the wild. Qualitative descriptions are presented along with experimental evidence for the phenomenon. The accumulated evidence is quite suggestive, implying sophisticated cognitive mechanisms, particularly in the great apes. Primates not only suppress or hide certain signals, but also project false images or seem to react to nonexisting external events to redirect another's attention. The predominantly descriptive evidence needs to be complemented by experiments on the possibility of attribution and intentional manipulation of other individuals' mental states.
Cannibalism in prehistoric Europe
Authors: Villa Paola 
Published: June 2005

AbstractThe key argument for the identification of prehistoric cannibalism is provided by analysis of close similarities in the treatment of human and animal remains. Such analysis requires precise data on depositional context, meticulous excavation records, detailed bone modification studies, a relatively large sample of human and animal postcranial bones, and data on local mortuary practices. With the exception of Fontbrégoua Cave, these necessary conditions are lacking at all Stone Age European sites where it has been hypothesized that cannibalism occurred. The alternative hypothesis of secondary burial practices has been proposed informally for some sites and, in a more formal and detailed way, for Krapina and Fontbrégoua. However, this hypothesis does not have a higher probability, is not justified by current data, and uses ethnographic analogies to prop up interpretations of materials for which contextual data are missing or have been neglected. At Fontbrégoua, cannibalism remains the simplest and most plausible explanation of the evidence; at Krapina and other sites the available evidence is insufficient to prove either secondary burial or cannibalism.
Why do female primates have such long lifespans and so few babies?orLife in the slow lane
Authors: Charnov Eric L. , Berrigan David 
Published: June 2005

AbstractA major goal of life history studies is to identify and explain features of the life history of individual species that follow broad rules across many groups of organisms, features that are characteristic of particular phylogenetic lineages, and features that are specific adaptations, to local ecological situations. In recent years we have developed a general theory of life history that interrelates many aspects of ontogeny and reproduction across a wide range of organisms. Contrasted to most other mammals, primates have long average adult lifespans and few babies per year for their adult body size. This new theory suggests that these aspects of life history follow directly from the fact that primates have slow individual growth rates. This slow growth rate is thus the basic phenomenon that needs explanation to understand primate slowness.
Diamonds in the desert: The discovery of Otavipithecus namibiensis
Authors: Conroy Glenn C. , Pickford Martin , Senut Brigitte , Mein Pierre 
Published: June 2005

AbstractThe mountains and deserts of Namibia hide many treasures—diamonds, gold, uranium, strategic minerals. But on the afternoon of June 4, 1991, we were searching Namibia's mountains for a rarer kind of stone, fossilized evidence of human evolution in southern Africa. What we found instead was the rarest “diamond” of all, one that no one had ever seen before on the African continent south of equatorial East Africa. What we found was incontrovertible evidence that prehuman “apes” were living in southern Africa millions of years before Australopithecus roamed the veld.
DNA and recent human evolution
Authors: Stoneking Mark 
Published: June 2005

AbstractThe study of recent human evolution, or the origin of modern humans, is currently dominated by two theories. The recent African origin hypothesis holds that there was a single origin of modern humans in Africa about 100,000 years ago, after which these humans dispersed throughout the rest of the world, mixing little or not at all with nonmodern populations. The multiregional evolution hypothesis holds that there was no single origin of modern humans but, instead, that the mutations and other traits that led to modern humans were spread in concert throughout the old world by gene flow, leading to genetic continuity among old world populations during the past million years. Although both of these theories are based on observations stemming from the fossil record, much discussion and controversy during the past six years has focused on the application and interpretation of studies of DNA variation, particularly mitochondrial DNA (mtDNA). The past year, especially, has brought new data, interpretations, and controversies. Indeed, I initially resisted writing this review, on the grounds that new information would be likely to render it obsolete by the time it was published. However, now that the dust is starting to settle, it seems timely to review various investigations and interpretations and where they are likely to lead. While the focus of this review is the mtDNA story, brief mention is made of studies of nuclear DNA variation (both autosomal and Y‐chromosome DNA) and the implications of the genetic data with regard to the fossil record and our understanding of recent human evolution.
Life history theory and evolutionary anthropology
Authors: Hill Kim 
Published: June 2005

AbstractLife‐history theory has been developed in biology to explain the variation in timing of fertility, growth, developmental rates, and death of living organisms, as well as events directly tied to these parameters. The theory is useful in explaining variations in age‐specific human fertility and mortality patterns, as well as understanding how the human life course evolved to patterns so divergent from those that characterize our close primate relatives. Surprisingly, this same theory can also be used to explain why people often ignore the long‐term consequences of behaviors that produce short‐term gain.
Hominoid trichotomy: A molecular overview
Authors: Bailey Wendy J. 
Published: June 2005

AbstractThe subject of this review is an issue that was hotly debated even before the emergence of molecular data into the field of primate systematics. It is an understatement to say that dissenting opinions exist as to whether the chimpanzee (Pan) or gorilla (Gorilla) is the closest relative of humans (Homo) or whether, in fact, a three‐way split in an ancestral population resulted in three separate lineages that are evolutionarily equidistant. The purpose of this review is to introduce the novice to the problems and methodologies of molecular phylogenetic analysis and to summarize the studies that have applied this approach in attempting to resolve the human‐African ape trichotomy. The intent is to present the contribution of each study to the resolution of higher primate relationships.