Elizabeth Erhart

Texas State University | TxSt · Department of Anthropology

Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs,...

Dietary data are used to categorize species diets, but these categorizations do not take into account the mutability of food resources in time or space, the level of interspecific competition in various communities as these resources change, nor the dietary flexibility of species. In this study, we assess the diets of three sympatric species, Eulem...

Closely related primate species sometimes exhibit diverse reproductive strategies. By comparing sympatric congeners, we can begin to elucidate the evolutionary processes shaping this extensive variation. Red-bellied lemurs (Eulemur rubriventer) and red-fronted lemurs (Eulemur rufifrons) are sympatric in parts of the eastern rainforests of Madagasca...

We present findings from 25 years of studying 13 species of sympatric primates at Ranomafana National Park, Madagascar. Long-term studies have revealed that lemur demography at Ranomafana is impacted by climate change, predation from raptors, carnivores, and snakes, as well as habitat disturbance. Breeding is seasonal, and each species (except Eule...

Although some conservationists accept that not all species can be saved, we illustrate the difficulty in deciding which species are dispensable. In this article, we examine the possibility that the integrity of a forest relies on its entire faunal assemblage. In Madagascar, one faunal group, the lemurs, accounts for the greatest biomass and species...

Most studies that examine the influence of climatic change on flora and fauna have focused on northern latitudes; however, there is increasing recognition that tropical regions are also being affected. Despite this, regions such as Madagascar, which are rich in endemic biodiversity but may have low adaptive capacity to climatic change, are poorly r...

Sterck and colleagues (Behaviour 134:749–774, 1997) focused attention on the evolutionary ecology of female social relationships within and between groups and proposed a model that distinguishes 4 categories of female relationships, which correspond to particular types of intra- and intergroup competition. They emphasized literature on haplorhines...

Eulemur fulvus rufus has been described as having stable multi-male/multi-female groups, a male-biased sex ratio, and female philopatry. However, in a 16-year study of this subspecies we documented a great deal of demographic change as several groups permanently fissioned, some groups disappeared, and new groups formed. We split the dataset into tw...

A variety of anthropoids travel efficiently from one food source to another, although there is disagreement over how this is accomplished over large-scale space. Mental maps, for example, require that animals internally represent space, geometrically locate landmarks, use true distance and direction, and generate novel shortcuts to resources. Alter...

Madagascar ranks as one of the world's top extinction hotspots because of its high endemism and high rate of habitat degradation. Global climate phenomena such as El Nino Southern Oscillations may have confounding impacts on the island's threatened biota but these effects are less well known. We performed a demographic study of Propithecu...

In this study, we compare the behavioral development of captive male vervet monkeys (Chlorocebus pygerythrus) and Sykes' monkeys (Cercopithecus albogularis) to male hybrids of these species. Focal animal sampling sessions were conducted on the study subjects from birth to 90 months of age. Behavioral categories (affiliative, approach, play, sexual,...

Although many Malagasy lemurs are thought to be female dominant and to have female feeding priority, to date the relationship between these behaviors has been rigorously established only in Lemur catta, and other ways that females might achieve feeding priority have not been examined closely. Erhart and Overdorff [International Journal of Primatolo...

Coordination of primate group movements by individual group members is generally categorized as leadership behavior, which entails several steps: deciding where to move next, initiating travel, and leading a group between food, water sources, and rest sites. Presumably, leaders are able to influence their daily foraging efficiency and nutritional i...

Infanticide might be described as a reproductive strategy employed by anthropoid primate males when they immigrate into new groups. But infanticide has rarely been observed in wild prosimian primates. For the Malagasy lemurs this may reflect one or more of the following: strict breeding seasons; relative monomorphism in canine tooth and body size;...

Our objective in this study was to evaluate whether a group of paternally related, subadult baboons (Papio cynocephalus) would preferentially interact with kin or nonkin when they had been raised apart from kin other than their mothers. Subjects and their mothers were removed from the breeding group and placed in alternate housing within 24 h after...

My aim in this study was to provide preliminary data on population density, habitat use and grouping patterns of the two primate species (black howler monkey and black-handed spider monkey) living in the eastern edge of the Montes Azules Biosphere Reserve, Chiapas, Mexico. There is limited information on the behavioral ecology of the study species,...