What is a hyena
Pro Research Analysisby
Searched over 200M research papers
Consensus Meter
Understanding Hyenas: Ecological and Social Diversity
Introduction to Hyenas
Hyenas belong to the family Hyaenidae, which includes only four living species: the aardwolf (Proteles cristata), the striped hyena (Hyaena hyaena), the brown hyena (Parahyaena brunnea), and the spotted hyena (Crocuta crocuta). Despite their limited number, hyenas exhibit remarkable ecological and social diversity, surpassing even larger families like canids and felids.
Evolutionary Background and Distribution
Hyenas are the last remnants of a once diverse family that peaked during the Late Miocene (12–6 million years ago) with at least 24 species. These ancient hyenas included both robust, bone-cracking forms and dog-like species in terms of appearance and feeding ecology. Today, hyenas are found only in Africa and the Middle East, occupying a variety of habitats such as deserts, montane forests, and open savannas.
Ecological Niches and Social Structures
Modern hyenas fill a wide array of ecological niches, ranging from specialized insectivores like the aardwolf to large predators like the spotted hyena. Their social structures are equally diverse, ranging from monogamous pairs to large, complex groups. All hyena species are largely nocturnal and have a distinctive sloping body profile due to their shorter hind legs. They communicate through erecting their manes and tails, facial expressions, and chemical signals from anal scent glands.
Conservation Status and Challenges
Striped Hyena
The striped hyena is one of the largest carnivores in forest and grassland ecosystems across Africa and Asia but is currently threatened throughout its range. In Nepal, the distribution of striped hyenas has significantly decreased, especially outside National Parks, confining them to lowlands and hill areas of western and central Nepal. Conservation efforts are crucial, particularly outside protected areas, to ensure their survival.
Brown Hyena
The brown hyena is the rarest of the four extant species, with an estimated population size of fewer than 10,000 individuals worldwide, and is listed as Near Threatened by the IUCN. Genetic studies reveal extremely low genetic diversity in brown hyenas, likely due to a continuous decline in effective population size that began around 1 million years ago and accelerated towards the end of the Pleistocene. Despite this low genetic diversity, there is no evidence of inbreeding in captive individuals, suggesting the existence of several potential subpopulations within the species.
Conclusion
Hyenas are a fascinating group of carnivores with a rich evolutionary history and diverse ecological roles. However, their survival is threatened by habitat loss and declining population sizes. Conservation efforts must be tailored to address the specific needs of each species to ensure their continued existence.
Sources and full results
Most relevant research papers on this topic