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1.
Clin Transl Oncol ; 23(3): 628-637, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32691365

RESUMO

BACKGROUND: Management of WHO grade II gliomas (LGG) can include a combination of observation, surgery, radiotherapy (RT), and chemotherapy; however, optimal management remains unclear in regards to RT. OBJECTIVE: The current study seeks to investigate the usage of RT in LGG and its effect on survival outcomes. METHODS: Patients with diagnosis codes specific for LGG were queried from the National Cancer Database (NCDB) during the years 2004-2016. Kaplan-Meier curves with log-rank testing, univariate and multivariate Cox regression analysis, and comparisons of estimated 3- and 7-year survival were performed to investigate the effect of RT on overall survival. RESULTS: 19,382 patients with LGG were identified with histologically confirmed disease. Kaplan-Meier testing demonstrated RT impacted survival in patients undergoing biopsy or no surgery (p < 0.0001), no chemotherapy (p < 0.0001), and in regimens with early RT (p < 0.0001) and high-dose RT (p < 0.0001). Cox multivariate regression demonstrated RT and age less than 40 (HR 0.93, 95% CI 0.89-0.97, p = 0.001), no chemotherapy (HR 0.82, 95% CI 0.77-0.87, p < 0.001), and astrocytoma histology (HR 0.72, 95% CI 0.66-0.79, p < 0.001) were associated with improved survival. 3-year survival of RT versus non-RT groups showed increased survival rates for age less than 40 years (+ 5.7%, p < 0.0001), no surgery or biopsy (+ 8.1%, p < 0.0001), no chemotherapy (+ 10.3%, p < 0.0001), mixed glioma (+ 6.7%, p < 0.0001), astrocytoma (+ 7.1%, p < 0.0001), and in regimens with early RT (+ 7.6%, p < 0.0001) and high-dose RT (+ 4.7%, p < 0.0001). CONCLUSION: This nationwide analysis of LGG patients found that RT was associated with improved survival outcomes in patients less than 40 years of age, with histology subtypes of astrocytoma and mixed glioma, undergoing biopsy or no surgery, and in regimens with early RT and high-dose RT.


Assuntos
Astrocitoma/radioterapia , Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Oligodendroglioma/radioterapia , Adulto , Fatores Etários , Astrocitoma/mortalidade , Astrocitoma/patologia , Astrocitoma/cirurgia , Biópsia , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Feminino , Glioma/mortalidade , Glioma/patologia , Glioma/cirurgia , Humanos , Estimativa de Kaplan-Meier , Masculino , Gradação de Tumores , Oligodendroglioma/mortalidade , Oligodendroglioma/patologia , Oligodendroglioma/cirurgia , Análise de Regressão , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
2.
Anim Cogn ; 22(4): 471, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28887811

RESUMO

Great apes give gestures deliberately and voluntarily, in order to influence particular target audiences, whose direction of attention they take into account when choosing which type of gesture to use. These facts make the study of ape gesture directly relevant to understanding the evolutionary precursors of human language; here we present an assessment of ape gesture from that perspective, focusing on the work of the "St Andrews Group" of researchers. Intended meanings of ape gestures are relatively few and simple. As with human words, ape gestures often have several distinct meanings, which are effectively disambiguated by behavioural context. Compared to the signalling of most other animals, great ape gestural repertoires are large. Because of this, and the relatively small number of intended meanings they achieve, ape gestures are redundant, with extensive overlaps in meaning. The great majority of gestures are innate, in the sense that the species' biological inheritance includes the potential to develop each gestural form and use it for a specific range of purposes. Moreover, the phylogenetic origin of many gestures is relatively old, since gestures are extensively shared between different genera in the great ape family. Acquisition of an adult repertoire is a process of first exploring the innate species potential for many gestures and then gradual restriction to a final (active) repertoire that is much smaller. No evidence of syntactic structure has yet been detected.


Assuntos
Comunicação Animal , Gestos , Hominidae , Idioma , Filogenia , Agressão , Animais , Atenção , Evolução Biológica , Humanos
3.
Behav Ecol Sociobiol ; 71(6): 96, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28596637

RESUMO

ABSTRACT: We describe the individual and combined use of vocalizations and gestures in wild chimpanzees. The rate of gesturing peaked in infancy and, with the exception of the alpha male, decreased again in older age groups, while vocal signals showed the opposite pattern. Although gesture-vocal combinations were relatively rare, they were consistently found in all age groups, especially during affiliative and agonistic interactions. Within behavioural contexts rank (excluding alpha-rank) had no effect on the rate of male chimpanzees' use of vocal or gestural signals and only a small effect on their use of combination signals. The alpha male was an outlier, however, both as a prolific user of gestures and recipient of high levels of vocal and gesture-vocal signals. Persistence in signal use varied with signal type: chimpanzees persisted in use of gestures and gesture-vocal combinations after failure, but where their vocal signals failed they tended to add gestural signals to produce gesture-vocal combinations. Overall, chimpanzees employed signals with a sensitivity to the public/private nature of information, by adjusting their use of signal types according to social context and by taking into account potential out-of-sight audiences. We discuss these findings in relation to the various socio-ecological challenges that chimpanzees are exposed to in their natural forest habitats and the current discussion of multimodal communication in great apes. SIGNIFICANCE STATEMENT: All animal communication combines different types of signals, including vocalizations, facial expressions, and gestures. However, the study of primate communication has typically focused on the use of signal types in isolation. As a result, we know little on how primates use the full repertoire of signals available to them. Here we present a systematic study on the individual and combined use of gestures and vocalizations in wild chimpanzees. We find that gesturing peaks in infancy and decreases in older age, while vocal signals show the opposite distribution, and patterns of persistence after failure suggest that gestural and vocal signals may encode different types of information. Overall, chimpanzees employed signals with a sensitivity to the public/private nature of information, by adjusting their use of signal types according to social context and by taking into account potential out-of-sight audiences.

4.
Anim Cogn ; 20(4): 755-769, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28502063

RESUMO

Great apes give gestures deliberately and voluntarily, in order to influence particular target audiences, whose direction of attention they take into account when choosing which type of gesture to use. These facts make the study of ape gesture directly relevant to understanding the evolutionary precursors of human language; here we present an assessment of ape gesture from that perspective, focusing on the work of the "St Andrews Group" of researchers. Intended meanings of ape gestures are relatively few and simple. As with human words, ape gestures often have several distinct meanings, which are effectively disambiguated by behavioural context. Compared to the signalling of most other animals, great ape gestural repertoires are large. Because of this, and the relatively small number of intended meanings they achieve, ape gestures are redundant, with extensive overlaps in meaning. The great majority of gestures are innate, in the sense that the species' biological inheritance includes the potential to develop each gestural form and use it for a specific range of purposes. Moreover, the phylogenetic origin of many gestures is relatively old, since gestures are extensively shared between different genera in the great ape family. Acquisition of an adult repertoire is a process of first exploring the innate species potential for many gestures and then gradual restriction to a final (active) repertoire that is much smaller. No evidence of syntactic structure has yet been detected.


Assuntos
Comunicação Animal , Gestos , Hominidae , Animais , Humanos , Idioma , Filogenia
5.
Am J Otolaryngol ; 36(4): 547-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25749259

RESUMO

PURPOSE: Esthesioneuroblastoma is an uncommon malignancy of the head and neck for which there is no defined treatment protocol. The purpose of this study is to report our experience with the treatment and patterns of failure of this disease. METHODS AND MATERIALS: From 1994 to 2012, 37 previously unreported patients with esthesioneuroblastoma were evaluated, and 32 eventually treated for cure at 2 academic medical centers. All patients were staged with Kadish criteria. The mean and median follow-ups were 96.1 and 76.5 months respectively (range 6-240 months). RESULTS: The Kadish stage was A in 6 patients, B in 13 patients, and C in 13 patients. Four patients were initially treated with concurrent chemo-radiation therapy. Twenty-eight patients were treated with primary surgery. Two (2) underwent open medial maxillectomy and 26 underwent craniofacial resection (open - 17, endoscopic - 9). Three patients received curative surgical resection only. Seven patients failed either within the cranial axis or distantly, 6 of the 7 are dead of disease, 10-194 months following initial treatment. Six patients had isolated neck recurrences, 4/6 were salvaged with neck dissection and additional chemo-radiation and remain alive 30-194 months following initial treatment. Estimated overall survival rate at 10 years was 78% based on Kadish and T stages. CONCLUSION: In this retrospective analysis of 32 patients, Kadish stage C and stage T3/T4 tumors were associated with worse outcome. Total radiation dose of 60 Gy, margin status, patient age, were not found to have significant prognostic value.


Assuntos
Estesioneuroblastoma Olfatório/terapia , Cavidade Nasal , Recidiva Local de Neoplasia/terapia , Neoplasias Nasais/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Intervalo Livre de Doença , Estesioneuroblastoma Olfatório/diagnóstico , Estesioneuroblastoma Olfatório/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Estadiamento de Neoplasias , Neoplasias Nasais/diagnóstico , Neoplasias Nasais/mortalidade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Falha de Tratamento , Estados Unidos/epidemiologia
7.
Anim Cogn ; 8(2): 114-21, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15871038

RESUMO

This experiment investigated whether domestic pigs can remember the locations of food sites of different relative value, and how a restricted retrieval choice affects their foraging behaviour. Nine juvenile female pigs were trained to relocate two food sites out of a possible eight in a spatial memory task. The two baited sites contained different amounts of food and an obstacle was added to the smaller amount to increase handling time. On each trial, a pig searched for the two baited sites (search visit). Once it had found and eaten the bait, it returned for a second (relocation) visit, in which the two same sites were baited. Baited sites were changed between trials. All subjects learnt the task. When allowed to retrieve both baits, the subjects showed no preference for retrieving a particular one first (experiment 1). When they were allowed to retrieve only one bait, a significant overall preference for retrieving the larger amount emerged across subjects (experiment 2). To test whether this preference reflected an avoidance of the obstacle with the smaller bait, 15 choice-restricted control trials were conducted. In control trials obstacles were present with both baits. Pigs continued to retrieve the larger bait, indicating they had discriminated between the two food sites on the basis of quantity or profitability and adjusted their behaviour accordingly when the relocation choice was restricted. This suggests for the first time that domestic pigs have the ability to discriminate between food sites of different relative value and to remember their respective locations.


Assuntos
Comportamento Apetitivo , Aprendizagem por Associação , Comportamento Alimentar/psicologia , Percepção Espacial , Sus scrofa/psicologia , Animais , Feminino
8.
Philos Trans R Soc Lond B Biol Sci ; 358(1431): 529-36, 2003 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-12689378

RESUMO

Non-human great apes appear to be able to acquire elaborate skills partly by imitation, raising the possibility of the transfer of skill by imitation in animals that have only rudimentary mentalizing capacities: in contrast to the frequent assumption that imitation depends on prior understanding of others' intentions. Attempts to understand the apes' behaviour have led to the development of a purely mechanistic model of imitation, the 'behaviour parsing' model, in which the statistical regularities that are inevitable in planned behaviour are used to decipher the organization of another agent's behaviour, and thence to imitate parts of it. Behaviour can thereby be understood statistically in terms of its correlations (circumstances of use, effects on the environment) without understanding of intentions or the everyday physics of cause-and-effect. Thus, imitation of complex, novel behaviour may not require mentalizing, but conversely behaviour parsing may be a necessary preliminary to attributing intention and cause.


Assuntos
Comportamento Imitativo , Animais , Comportamento Animal/fisiologia , Gorilla gorilla , Intenção , Comportamento Social
9.
Anim Cogn ; 4(3-4): 347-61, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24777525

RESUMO

The manipulative actions of mountain gorillas Gorilla g. beringei were examined in the context of foraging on hard-to-process plant foods in the field, in particular those used in tackling thistle Carduus nyassanus. A repertoire of 72 functionally distinct manipulative actions was recorded. Many of these actions were used in several variants of grip, finger(s) and movement path, both by different individuals and by the same individual at different times. The repertoire appears somewhat greater than that observed in comparable studies of monkeys, but a far more striking difference is found in the use of differentiated actions in concert. Mountain gorillas routinely and frequently deal with problems that involve: (1) bimanual role differentiation, with the two hands taking different roles but synchronized in time and space, and (2) digit role differentiation, with independent control of parts of the same hand used for separate purposes at the same time. The independent control that allows these abilities, so crucial to human manual constructional ability, is apparently general in African great apes. Role differentiation, between and within the hand, is evidently a primitive characteristic in the human arsenal of skills.

10.
J Comp Psychol ; 114(1): 13-21, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10739308

RESUMO

Lateral preference was examined in spontaneous feeding actions in 2 troops of wild vervet monkeys (Cercopithecus aethiops). Processing of 4 foods (termites, leaf shoots, sugarcane, and fruit) was studied. Actions included unimanual reaching to moving objects, operating from an unstable posture, and coordinated bimanual processing. Between 19 and 31 subjects were available, according to the task. In 2 tasks, laterality of 2 independent stages was measured separately, giving 6 measures in all. On 4 of these measures, most monkeys were ambipreferent, and only a few showed significant hand preferences. Only for termite feeding and detaching material from fruits did the majority show significant lateralization; no tasks elicited exclusive use of 1 hand. Preference appeared labile, because in 2 tasks, population trends reversed with increasing age. No population trends to left or right were found; instead, these monkeys showed ambilaterality, with lateralization associated with task complexity.


Assuntos
Chlorocebus aethiops/psicologia , Comportamento de Escolha , Comportamento Alimentar , Lateralidade Funcional , Animais , Animais Selvagens , Feminino , Preferências Alimentares/psicologia , Masculino
11.
In Vitro Cell Dev Biol Anim ; 35(6): 357-63, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10476924

RESUMO

Embryonic development is determined by preset intrinsic programs and extrinsic signals. To explore the possibility that transcription factors are present at the onset of development, preparations of yolk, albumin, and blastoderm from unfertilized and fertilized white Leghorn chicken eggs were screened by a panel of 16 transcription factor antibodies with Western blot techniques. Yolk was positive for 13 transcription factors, whereas blastoderm was positive for 10, and albumin was positive for 5. In yolk, several transcription factors, GATA-2, E2F-1, MyoD, and TFIID, were developmentally regulated. These results indicate that intracellular yolk and extracellular albumin contain transcription factors which presumably influence early chick embryonic development from prefertilization to the late blastoderm stage. Thus, the utility of preset maternal transcription factors within yolk and albumin complement maternally derived mRNA to determine the early development of the zygote.


Assuntos
Albuminas/química , Blastoderma/química , Gema de Ovo/química , Fatores de Transcrição/análise , Animais , Embrião de Galinha
12.
Behav Brain Sci ; 21(5): 667-84; discussion 684-721, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10097023

RESUMO

To explain social learning without invoking the cognitively complex concept of imitation, many learning mechanisms have been proposed. Borrowing an idea used routinely in cognitive psychology, we argue that most of these alternatives can be subsumed under a single process, priming, in which input increases the activation of stored internal representations. Imitation itself has generally been seen as a "special faculty." This has diverted much research towards the all-or-none question of whether an animal can imitate, with disappointingly inconclusive results. In the great apes, however, voluntary, learned behaviour is organized hierarchically. This means that imitation can occur at various levels, of which we single out two clearly distinct ones: the "action level," a rather detailed and linear specification of sequential acts, and the "program level," a broader description of subroutine structure and the hierarchical layout of a behavioural "program." Program level imitation is a high-level, constructive mechanism, adapted for the efficient learning of complex skills and thus not evident in the simple manipulations used to test for imitation in the laboratory. As examples, we describe the food-preparation techniques of wild mountain gorillas and the imitative behaviour of orangutans undergoing "rehabilitation" to the wild. Representing and manipulating relations between objects seems to be one basic building block in their hierarchical programs. There is evidence that great apes suffer from a stricter capacity limit than humans in the hierarchical depth of planning. We re-interpret some chimpanzee behaviour previously described as "emulation" and suggest that all great apes may be able to imitate at the program level. Action level imitation is seldom observed in great ape skill learning, and may have a largely social role, even in humans.


Assuntos
Comportamento Imitativo/fisiologia , Aprendizagem/fisiologia , Animais , Comportamento Animal/fisiologia , Humanos , Ratos , Percepção Social
13.
Folia Primatol (Basel) ; 68(3-5): 254-64, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9360309

RESUMO

In a field experiment, tape-recorded vocalizations of spider monkeys (Ateles geoffroyi) were played back to investigate whether individuals were able to discriminate between group members and strangers. Monkeys responded remarkably similarly in the two cases, with no significant difference found between the numbers of calls given by an individual, or the types of call given. However, a group was more likely to give some vocal reaction when hearing a stranger's call than when hearing one from an individual of their own community. Further, the only instances in which agonistic territorial behaviours occurred were in reaction to strangers' playbacks. No significant effects on the response given were produced by the sex of the caller, the location and time of day of the broadcast, the size of the subgroup hearing the call or the activity in which they were involved. These results are discussed with respect to acoustic, social and ecological factors that may lead to the apparent lack of vocal discrimination of strangers within the community range.


Assuntos
Cebidae/psicologia , Discriminação Psicológica , Comportamento Social , Vocalização Animal , Animais , Animais Selvagens , Percepção Auditiva , Cebidae/fisiologia , Ecologia , Feminino , Audição , Libéria , Masculino , Gravação em Fita
14.
Pediatr Neurosurg ; 23(4): 182-6; discussion 186-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8835207

RESUMO

A retrospective analysis of 100 children followed at Children's Memorial Hospital, Chicago, who underwent surgery for a spinal lipoma was performed. The mean follow-up was 5 years. We found that an operation performed during the 1st year of life with the goal of untethering the spinal cord and debulking the spinal lipoma was safe and effective, whereas a cosmetic (nonuntethering) procedure always led to delayed postoperative deterioration (symptomatic tethered cord). Of the infants that presented with motor, urologic or orthopedic symptoms, 39% improved, 58% stabilized, while 3% worsened as a result of surgery. No asymptomatic infant deteriorated postoperatively and 93% of these children remained symptom-free at follow-up (mean follow-up was 44 months). The overall outcome of infants after untethering procedures in this study was significantly better than the natural history of spinal lipomas. Several risk factors were identified that may predispose children to delayed postoperative deterioration: an initial cosmetic procedure; the presence of preoperative symptoms, and the presence of a lipomyelomeningocele.


Assuntos
Lipoma/congênito , Neoplasias da Medula Espinal/congênito , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/cirurgia , Feminino , Seguimentos , Humanos , Lactente , Lipoma/diagnóstico , Lipoma/cirurgia , Masculino , Meningomielocele/diagnóstico , Meningomielocele/cirurgia , Exame Neurológico , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Espinha Bífida Oculta/diagnóstico , Espinha Bífida Oculta/cirurgia , Neoplasias da Medula Espinal/diagnóstico , Neoplasias da Medula Espinal/cirurgia , Resultado do Tratamento
15.
Am J Primatol ; 37(2): 127-141, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-31936945

RESUMO

Primate cognition is believed to have adapted during evolution in response to complexity, stemming from either social or environmental challenges. Arguments favoring one or another domain as the predominant spur to increased intelligence have been proposed on the basis of the inherent complexity of problems facing primates and the sophistication of their observed behavioral response. A review of recent findings shows that cognitive differences between primates are well revealed by naturally posed problems. Current evidence shows a sensitivity to fine social distinctions in haplorhine primates, associated with complex social manipulations and neocortical enlargement, compared to strepsirhines. Several aspects of foraging behavior also suggests cognitive sophistication in various primates. Depth of understanding, however, is greater in great apes than in monkeys; this applies to both spheres, social (e.g., comprehending mental states) and nonsocial (e.g., comprehending physical mechanism and hierarchical organization of behavior). The increased representational understanding in great apes is not associated either with more manipulative social actions or with neocortical enlargement, compared to monkeys. This evidence supports theories of a social origin of cognition for those aspects shared by monkeys and apes but not for the unique qualitative differences of great apes. Task complexity is difficult, perhaps impossible, to measure or compare across domains; any such comparison would certainly be premature at present for primates. Behavioral skill, though in principle simpler to compare, is at present difficult to assess when there is no common currency of theory-building. With the aim of encouraging comparisons of data from laboratory and field and from social and technical problems, a preliminary exploration is made with a notation derived from artificial intelligence; this is shown to be capable of representing theories of complex behavior in both social and technical domains. © 1995 Wiley-Liss, Inc.

16.
Neurosurgery ; 35(2): 321-6; discussion 326, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7969844

RESUMO

Two cases of chronic spinal cord abscess are reported, and the relevant literature is reviewed with emphasis on the last 20 cases. Presentation, cause, modern diagnostic testing, operative findings, treatment choices, and prognosis are all discussed. Significant changes in the presentation, management, and outcome in these more recent cases are emphasized.


Assuntos
Abscesso/diagnóstico , Doenças da Medula Espinal/diagnóstico , Abscesso/cirurgia , Idoso , Antibacterianos , Terapia Combinada , Quimioterapia Combinada/uso terapêutico , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Medula Espinal/patologia , Medula Espinal/cirurgia , Doenças da Medula Espinal/cirurgia
17.
Folia Primatol (Basel) ; 61(1): 1-20, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8144106

RESUMO

Information on the chemical composition of baboon foods from the Laikipia Plateau, Kenya, is presented. Despite some differences in methods, results of analyses performed on the same foods at different sites were found to be extremely consistent, encouraging the view that meaningful intra- and interspecific comparisons of diet selection are feasible. Contrary to assumptions in the literature, no relationship between the abundance of food types and their chemical composition was found, nor was the foliage eaten by the baboons found to be a low-quality or high-fibre item in comparison with fruits and storage organs. Emphasis is placed on the need for caution in the use of simplistic dietary taxonomies which imply phytochemical and ecological homogeneity within broad food categories. Comparisons between three species revealed marked differences in the chemical composition of their diets; in particular, baboon diets were found to be higher in protein and lower in fibre than those of either lowland gorillas or Malaysian leaf monkeys, and differences in condensed tannin levels were also found. The relationship between these differences and the socio-ecology of the three species is discussed.


Assuntos
Ração Animal/análise , Dieta , Papio/fisiologia , Plantas Comestíveis/química , Alcaloides/análise , Ração Animal/normas , Animais , Gorduras na Dieta/análise , Fibras na Dieta/análise , Proteínas Alimentares/análise , Feminino , Abastecimento de Alimentos , Masculino , Valor Nutritivo , Fenóis/análise , Plantas Comestíveis/classificação , Taninos/análise , Água/análise
18.
Cortex ; 27(4): 521-46, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1782788

RESUMO

Manual dexterity of 44 wild gorillas of all ages and both sexes was investigated on six naturally acquired feeding tasks of varied logical structure, which included multi-stage and bimanually coordinated procedures. At least 400 min observation of feeding per animal, and analysis at the level of bouts rather than individual actions, can be expected to produce statistically robust results; 22 years background data allowed effects of genealogy and injury to be investigated. Five tasks elicited very strong hand preferences in most animals (weakest on the simplest task), while one was usually performed with a strategy in which left and right hands were used symmetrically; the preferences were fully established at 3 years old. Preferences were highly correlated within each of two sets of tasks, but between the two sets there was no correlation across animals in direction or strength of preference. No population trends towards left or right handers were found in either set of tasks, or both sets pooled; distributions were U-shaped and approximately symmetric, with a slight bias towards right-handed fine manipulation in one set of tasks. Processing efficiency was only slightly greater with the preferred hand, and similar in left- and right-handed animals. Neither direction nor strength of hand preference showed a tendency to run in families, but females showed greater strength of preference. Major injury masked strong hand preference, but injuries could not account for the overall distribution of preference; instead this may reflect inbreeding. Feedback acting on initially random hand choices, and imitation at the "program" level rather than slavish copying of acts, are proposed to account for the results.


Assuntos
Lateralidade Funcional/fisiologia , Gorilla gorilla/fisiologia , Desempenho Psicomotor/fisiologia , Envelhecimento/fisiologia , Animais , Comportamento Alimentar/fisiologia , Feminino , Traumatismos da Mão/psicologia , Masculino , Estações do Ano , Caracteres Sexuais
19.
Philos Trans R Soc Lond B Biol Sci ; 334(1270): 187-95; discussion 195-7, 1991 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-1685577

RESUMO

As large-bodied savannah primates, baboons have long been of special interest to students of human evolution: many different populations have been studied and dietary comparisons among them are becoming possible. Baboons' foraging strategies can be shown to combine high degrees of flexibility and breadth with selectivity. In this paper we develop and test multivariate models of the basis of diet selection for populations of montane and savannah baboons. Food selection is positively related to protein and lipid content and negatively to fibre, phenolics and alkaloids. Seasonal changes in dietary criteria predicted by these rules are tested and confirmed. Although nutritional bottlenecks occur at intervals, a comparison between long-term nutrient intakes in four different populations indicates convergence on lower degrees of variation than exist in superficial foodstuff profiles.


Assuntos
Dieta , Preferências Alimentares , Papio/fisiologia , Aclimatação , África Austral , Animais , Proteínas Alimentares , Frutas , Geografia , Plantas , Estações do Ano , Zea mays
20.
Am J Primatol ; 20(4): 313-329, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-32075347

RESUMO

Instead of close and differentiated relationships among adult females, the accepted norm for savanna baboons, groups of Drakensberg mountain baboons (Papio ursinus) showed strong affiliation of females towards a single male. The same male was usually the decision-making animal in controlling group movements. Lactating or pregnant females focused their grooming on this "leader" male, producing a radially patterned sociogram, as in the desert baboon (P. hamadryas); the leader male supported young animals in the group against aggression and protected them against external threats. Unlike typical savanna baboons, these mountain baboons rarely displayed approach-retreat or triadic interactions, and entirely lacked coalitions among adult females. Both groups studied were reproductively one-male; male-female relationships in one were like those in a unit of a hamadryas male at his peak, while the other group resembled the unit of an old hamadryas male, who still leads the group, with a male follower starting to build up a new unit and already monopolizing mating. In their mountain environment, where the low population density suggests conditions as harsh for baboons as in deserts, adults in these groups kept unusually large distances apart during ranging; kin tended to range apart, and spacing of adults was greatest at the end of the dry, winter season. These facts support the hypothesis that sparse food is responsible for convergence with hamadryas social organization. It is suggested that all baboons, though matrilocal, are better categorized as "cross-sex-bonded" than "female bonded".

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