Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Anthony B. Rylands is active.

Publication


Featured researches published by Anthony B. Rylands.


Journal of Human Evolution | 1989

Sympatric Brazilian callitrichids: The Black Tufted-Ear Marmoset, Callithrix kuhli, and the Golden-headed Lion Tamarin, Leontopithecus chrysomelas

Anthony B. Rylands

Abstract This report describes a study of Callithrix kuhli and Leontopithecus chrysomelas, sympatric in a remnant forest of the Atlantic coast of Brazil. Quantitative observations of two groups were carried out for three months each during 1980. Information on the activity budgets, activity heights and feeding and ranging behavior is compared to examine ecological differences between the species. C. kuhli gouges tree trunks to obtain exudates, forages for animal prey in a foliage-gleaning fashion and takes smaller prey in the lower levels of the forest. They occupy small home ranges, approximately 10 ha, centred on a principal exudate tree. Within their range they have access to fewer sources of fruits than L. chrysomelas, which occupies large ranges of approximately 40 ha, L. chrysomelas uses the upper levels of the forest to forage in a more manipulative fashion at specific sites, such as epiphytic bromeliads, where they take generally larger prey. C. kuhli uses dense vegetation for sleeping sites whereas L. chrysomelas uses tree holes.


American Journal of Primatology | 1996

Habitat and the evolution of social and reproductive behavior in callitrichidae

Anthony B. Rylands

The numerous remarkable traits characterizing the ecology and behavior of callitrichids have inspired considerable research and discussion of the flexible mating system (cases of monogamy, polygyny, and polyandry), cooperative breeding, reproductive inhibition by dominant females, rapid reproductive rate, significance of dietary differences (gum feeding, frugivory, and insectivory), and demographics and social characteristics of the four genera, Cebuella, Callithrix, Saguinus, and Leontopithecus. The majority of functional explanations evaluate costs, benefits, and alternative strategies but do not address the critical selective forces that led to the behaviors in the first place. In this paper, it is argued that Callithrix and Saguinus evolved to occupy a small insectivore/frugivore niche in secondary growth forest patches (gaps arising from tree falls), and other successional forests and edge habitats; that Cebuella evolved to occupy a gum‐feeding/insectivore niche in inundated forest; and that Leontopithecus is above all a small animal predator/frugivore and a mature forest genus. The keys to explanations concerning the evolution of the social and reproductive systems of these animals lie in an understanding of the resource base in these different habitats. Finally, it should be remembered that studies of callitrichids have in the main part been carried out in habitats highly altered by human activities (especially the Brazilian Atlantic forest, home to marmosets and lion tamarins) and are not the environments in which their social and breeding behavior evolved.


Folia Primatologica | 1997

Conservation of Neotropical Primates: Threatened Species and An Analysis of Primate Diversity by Country and Region

Anthony B. Rylands; Russell A. Mittermeier; Ernesto Rodríguez-Luna

Primates are important indicators for tropical forests as a fundamental component in the establishment of strategies for biodiversity conservation in biomes, regions and countries. Priority setting at


Primates | 2000

Feeding behavior of Geoffroy's marmoset (Callithrix geoffroyi) in an Atlantic forest fragment of South-eastern Brazil

Marcelo Passamani; Anthony B. Rylands

We report on the diet and feeding behaviour of a group of Geoffroys marmosets (Callithrix geoffroyi) in an Atlantic forest fragment in south-eastern Brazil, studied during the period February 1993 to Januaray 1994. Major food categories were gums (68.6%) fruits (15%), and small animal prey (invertebrates 14.6% and vertebrates 0.8%). Dietary changes were observed between the wet and dry seasons, although they were not statistically significant. Insects and gums were consumed throughout the year but fruits were more prevalent in the diet in the wet season. Plant species exploited for their gums includedInga stipularis, followed byAcacia paniculata, Paulinia carpopodia, andBauhinia angulosa. Chemical analysis of the gum of the four species most used all presented high values for carbohydrates and crude proteins. Fruits of an unidentified species of Myrtaceae (sp. 2) were consumed the most. Animal prey consisted mainly of insects, arachnids, snails, and in three cases, lizards and frogs, with orthopterans being the most prevalent insect prey. This study demonstrates thatC. geoffroyi efficiently exploits resources typically available in secondary and disturbed forest habitat. The main threat to the species is forest destruction, degradation, and fragmentation, but the management of small forest fragments may be an effective corservation strategy.


Folia Primatologica | 1997

Geographic Distribution of the Golden-Headed Lion Tamarin, Leontopithecus chrysomelas: Implications for Its Management and Conservation

Luiz Paulo de S. Pinto; Anthony B. Rylands

The geographic distribution and conservation status of the golden-headed lion tamarin, Leontopithecus chrysomelas, were studied during a survey carried out through an area of about


International Journal of Primatology | 1998

Scientific Nomenclature of the Red Howlers from the Northeastern Amazon in Brazil, Venezuela, and the Guianas

Anthony B. Rylands; Douglas Brandon-Jones

Cytogenetic and morphological studies have begun to reexamine the taxonomy of the red howlers Alouatta seniculus which live throughout the northern and western Amazon basin, in the Guianas, and from northern Colombia and Venezuela, south to Bolivia. We briefly review the current state of knowledge of the taxonomy and distributions of red howlers, in particular, that of the Guianan subspecies. Recently, two names have been applied to populations from this region, Simia straminea Humboldt, 1812, and Alouatta macconnelli Elliot, 1910. Allen (1911, 1916) unquestioningly accepted the validity of A. macconnelli from the Guyana coast, but most subsequent taxonomic revisions (Cruz Lima, 1945; Cabrera, 1957; Husson, 1978) have synonymized it with S. straminea. Tate (1939) and Hill (1962) listed Alouatta seniculus macconnelli, but both doubted its validity. Nevertheless, recent cytogenetic and morphological studies, without due consideration of the taxonomic history of the two scientific names, have led to the resurrection of A. macconnelli, as distinct from S. straminea. The use of the name Alouatta macconnelli has evidently arisen from a cursory reading of Hill (1962) or an uncritical interpretation of his provisional subspecific distribution map or both. There are also contradictory interpretations of a reciprocal translocation as indicating that Simia straminea and Alouatta macconnelli are separate species (Bonvicino et al., 1995) or the same subspecies (Sampaio et al., 1996). Doubts about the type locality of Simia straminea Humboldt, 1812, as given by Hill (1962), led us to research its original description and to conclude that Simia straminea is a synonym of Alouatta caraya and therefore unavailable for Alouatta seniculus. Before A. macconnelli is accepted as the next available name for the Guianan red howlers, however, we advocate a thorough review of Guianan, Venezuelan, and Colombian red howler subspeciation, with due consideration for the taxonomic status of Mycetes auratus and Mycetes laniger Gray, 1845. We note that Alouatta guariba (Humboldt, 1812) is a senior synonym of Alouatta fusca (Saint-Hilaire, 1812).


Archive | 1996

Translations of Chapter Summaries

Laura Cancino; Anthony B. Rylands; Horacio Schneider; Alfred L. Rosenberger; Gustavo Ab da Fonseca; Yuri L. R. Leite; Gustavo Russell A. Mittermeier; Stephen F. Ferrari; Maria Aparecida Lopes; Marilyn A. Norconk; Robert W. Sussman; Jane E. Phillips-Conroy; Michael L. Power; Brian J. Stafford; Andrew J. Baker; Benjamin B. Beck; James M. Dietz; Devra G. Kleiman; Lesa C. Davis; H. Kátia; M. Corrêa; Paulo E. G. Coutinho; Leslie J. Digby; Claudio E. Barreto; Anne Savage; Charles T. Snowdon; Humberto Giraldo; Paul A. Garber; Francine L. Dolins; Susan M. Ford

Analise cladistica das sequencias dos genes Epsilon-globin a e IRBP fornece informacāe complementar importante para urn esboco das principais linhas da filogenia dos macacos do Novo Mundo. As abordagens morfologicas e de genetica molecular sao razoavelmente consistentes com as evidencias disponiveis atraves do reg istro fossil , significando que as formas modernas fornecem uma boa base para o desenvolvimento de uma classificācao dos platirrineos, e que o entendimento das relacōes entre fosseis podem ser facil itados com a inclusao dos generos viventes nas analises. Os estudos moleculares e morfologicas fortalecem a ideia de tres grandes grupos modernos, possivelmente divergindo num intervalo de tempo relativamente curto . Considerando as discordâncias nos estudos da sistematica de platirrineos nas ultimas decadas - a correta localizacoo filogenetica de Cebus, Saimiri, Aotus e Callicebus - a cornbina#x00E7;oo das evidencias colocam Callicebus definitivamente como parente dos pitecineos. Elas reforcam tambem a ligacoo entre Saimiri e os calitriquineos, o elo entre Cebus e Saimiri, e sua associacoo com calitriquineos como uma linhagem monofiletica do grupo dos «cebideos». Os dados de DNA divergem, porem, com a colocacoo de Aotus como uma linhagem basal desse agrupamento, urn achado inconsistente com as evidencias morfologicas. A analise de DNA tambem aponta a necessidade de uma reconsideracoo da taxonomia do genero Callitrhix, que talvez noo seja monofiletica. Os dados confirmam parcialmente o padroo de ramificacoo do clade dos atelideos, posicionando Alouatta como a linhagem mais velha. Problemas que permanecem dentro dos calitriquineos e atelineos incluem: 1)os afinidades precisas entre os atelineos, Lagothrix, Ateles e Brachyt eles; e 2) a sequencia de ramificacoo dentre os calitriquineos, i.e., Callithrix/Cebuella, Leontopithecus , Saguinus e Callimico.


Conservation Biology | 2005

The fate of the amazonian areas of endemism

José Maria Cardoso da Silva; Anthony B. Rylands; Gustavo A. B. da Fonseca


Archive | 1994

Livro vermelho dos mamíferos brasileiros ameaçados de extinçao

Gustavo A. B. da Fonseca; Anthony B. Rylands; Cláudia M. R. Costa; Ricardo Botnfim Machado; Yuri L. R. Leite


Archive | 2005

Os corredores ecológicos das florestas tropicais do Brasil

José Márcio Ayres; Gustavo A. B. da Fonseca; Anthony B. Rylands; Helder L. Queiroz; Luiz Paulo de S. Pinto; Donald Masterson; Roberto B Cavalcanti

Collaboration


Dive into the Anthony B. Rylands's collaboration.

Top Co-Authors

Avatar

Russell A. Mittermeier

State University of New York System

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Luiz Paulo de S. Pinto

Universidade Federal de Minas Gerais

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Katrina Brandon

Conservation International

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Stephen F. Ferrari

Universidade Federal de Sergipe

View shared research outputs
Top Co-Authors

Avatar

Yuri L. R. Leite

Universidade Federal do Espírito Santo

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge