Dung middens, also known as dung hills, [1] are piles of dung that mammals periodically return to and build up. [2] They are used as a form of territorial marker. A range of animals are known to use them including steenbok, [3] hyrax, [4] and rhinoceros. [5] Other animals are attracted to middens for a variety of purposes, including finding food and locating mates. [5] Some species, such as the dung beetle genus Dicranocara of the Richtersveld in South western Africa spend their whole lifecycle in close association with dung middens. [5] Dung middens are also used in the field of paleobotany, which relies on the fact that each ecosystem is characterized by certain plants, which in turn act as a proxy for climate. [6] Dung middens are useful as they often contain pollen which means fossilized dung middens can be used in paleobotany to learn about past climates. [7] [8] [9]
The common hippopotamus has been known to use dung middens as a social tool. The middens are created and maintained by bulls to mark territorial boundaries. [10] To mark their scent upon a midden, the bull will approach the midden in reverse and simultaneously defecate and urinate on the mound, using its tail to disperse, or paddle, the excrement. [11] This action is called dung showering and thought to assert dominance. The middens, usually several feet across, are constantly maintained during the bulls' travels in the night and day. [12]
Dung-midden production is also observed in the white and black rhinoceroses. The middens are shown to provide cues as to the age, sex, and reproductive health of the producer. [13] Some of the middens can be 65 feet across. Dung beetles are frequently found in these middens and lay their eggs within the mounds. Their presence and activity in the middens also aid in pest and parasite control. [14] Unlike the hippopotamus, rhino dung middens are shared between individuals that are not necessarily related.
White rhino middens are distinguished by a black color and a primarily grass composition whereas black rhino middens tend to be brown and contain more twigs and branches, a product of the distinct diets. [15]
Midden formation in insects was first observed in black garden ants, Lasius niger. The middens created by the ants are called "kitchen middens" and are composed of food scraps, ant corpses, and other detritus. [16] A reason for the behavior has yet to be determined though it is thought to serve as a feeding ground for larvae.
The dry bush weasel lemur and southern gentle lemur are known to construct middens. It is thought that these act primarily as communal latrines and communication tools, signaling dominance and other social cues, for families spread over large tracts of land. [17]
Hyrax, or Procavia, are small herbivorous mammals from across the African continent and normally inhabit in rock shelters, not typically wandering more than 500 meters from their shelter for fear of predation. These organisms use fixed dung middens for urinating and defecation, often under overhanging rocks in protected areas. Layers of dung are quickly hardened and sealed by Hyraceum, creating mainly horizontal middens. [18]
Middens created by antelopes, as well as other herbivores, play an important role by providing nutrients to certain areas of land. It has been described that duiker and steenbok antelopes defecate in exposed sites, generally on sandy soil, thus enriching the nutrient-deficient areas, as well as depositing plant seed there. [19]
Many gazelle species use middens (see also Animal latrine) for activities related to territory maintenance, advertisement and olfactory communication. [20] Due to the investment required to maintain a midden, it is likely that middens would not be randomly placed throughout the environment, but rather would be distributed on different landmarks. Placing middens on conspicuous sites could attract the attention of hunters and provide the hunters with information about the location and activity of their prey. A group of researchers examined midden selection and use by mountain gazelles ( Gazella gazelle) in central Saudi Arabia and hypothesized that if middens are used for territorial or communication purposes, then they would tend to be placed at the largest trees in the immediate area. Additionally, if mountain gazelle midden selection and use was predictable, then this would corroborate poachers' claims that gazelles are easy to hunt because of their predictable behavior. [20] Ultimately it was found that midden size and the freshness of newly deposited feces could inform poachers about the gazelles' rates of midden use and potentially which middens are used more often. It was also found that middens are important communication centers for the mountain gazelles, and they are used by both sexes and by gazelles of various ages. [20]
The widespread presence of dung midden use throughout the animal kingdom is coupled with a distinct variation in how dung middens are used from species to species. Dung midden use has been implicated in the context of both intraspecific markers of territory, [21] [20] sexual availability, [22] and a part of anti-parasite behavior, [23] but also as an essential part of the ecosystem, with interspecies interactions between the creators and users of dung midden piles. [24] In some cases, it has been found that midden piles are the focal points of grazing lawns, not the other way around, as demonstrated by high frequency of grazing when old middens are present. [25]
Territory or home-range maintenance is found in many species of animals as a way to divide resources, including food and mates. [26] Often markers are employed to define such territories, and dung middens are one form of the markers employed. An example of dung midden use for territorial marking is found in the mountain gazelle, in which latrines/dung middens are found in the home-range cores and serve as a concentrated area to repel intruders while facilitating communication amongst the members of the female group. [21] This method of dung midden use is distinct from other species such as the Thornson's gazelle and the Günther's dik-dik, both of which use dung middens as peripheral territory markers instead. [27] [28]
Olfactory communication through dung middens can also indicate sexual availability to conspecifics. In white rhino dung, a mixture of volatile organic compounds present signal the defecator's sex and age class, and depending on whether they are a male or female, also indicate the male territorial status or female oestrous state. [22] Furthermore, dung middens act as a communication center for white rhino groups since the species practices communal defecation, allowing for these signals to easily reach potential mates. [22]
Dung with high parasite loads are a significant source of fecal-oral transmitted parasites, which impose a high cost on individual fitness in wild ungulates. [29] [30] Quantifying studies of parasite loads in dung midden piles of free ranging dik-dik found that nematode concentrations were elevated in the vicinity of middens in comparison to single fecal-pellet groups or dung-free areas. [23] Further feeding experiments found that the dik-diks tend to avoid the areas around dung middens when feeding, implying selective defecation and selective foraging where fecal avoidance could play a part in anti-parasite behavior in this species. [23]
Termites are usually viewed as both herbivores and decomposers when present within an ecological community. In some cases, they are the link between mammalian consumers and the microbial decomposers that perform the final breaking down of organic matter within the local cycle of nutrients. A case of this relationship between termites and mammalian dung middens is observed in South Africa, between the endemic blesbok and harvester termites. [31] The blesbok have been observed to deliberately place dung middens when they are in the vicinity of the harvester termite mounds. It has been suggested that this could be due to the fact that termite mounds are built on ground where the surrounding is cleared. This allows the blesboks greater ability to detect predators if foraging in the area, and termite presence in the vicinity could be an indicator of richer resources available from recycling of nutrients. Since decomposers such as termites increase the quality of the surrounding vegetation for foraging, this suggests that there is a positive evolutionary feedback within this interaction, with both participants in this interaction providing resources for the other. [24] [31]
Pollen that becomes fossilized in dung midden can provide information about the climate and environment during the time period when it was fossilized. This provides researchers with a better understanding of what historical environmental changes may have occurred leading up to the biodiversity and present day environment of various places.
Fossilized hyrax (small herbivorous mammals resembling rodents but more closely associated with elephants and manatees) dung has been found in a rock shelter on the Brandberg Mountain in Namibia, has been found to possess fossilized pollen. Radiocarbon dating places it between 30,000 years ago to modern times, making it the first evidence of pollen from the Late Pleistocene in south-western Africa. The pollen is preserved by layers of dung that are piled upon each other and sealed by urine. The dung found from this time is that of the family Asteraceae, a family not known to be found in Namibia or deserts. This suggests that climate in this area may have been tropical during this time, but it is also hypothesized that the spores were spread either aromatically or aquatically from another location.
In an earlier Brandberg Mountain sample from 17,000 years ago, Stoebe pollen was found in dung. There is also the presence of fern-spores indicating a moist climate during that time. This moisture would most likely be from melting and evaporating glaciers and not heavy rain. [32]
Sources of midden as old as 6,000 years ago can also be used to view the climate through the presence of certain pollen and the attributed rainfall necessary for those plants to be present and flowering. However, the changing presence of some plants can also be due to erratic conditions such as grazing and human interference by Nomadic people. Although, this is not thought to explain all of the aridity and variation of the area at certain times. The presence of certain flowering plants during the mid-Holocene that require more moisture leads to a conclusion of increased summer rainfall. This also accounts for the seasonal variability as many of plants found in the dung do not rely upon winter rain. [18]
Much is unknown about the origins of the unique biodiversity in the Namib desert. It has an arid climate and granitic substrate, which does not favor the preservation of organic material that would typically help provide insight into the history of the biodiversity. [33] Common artifacts typically used to study environmental conditions such as lake or swamp deposits, caves, river systems, or dune-fields do not exist. [33] Thus it has been difficult to understand the history of the Namib desert. Through the use of dung middens found in various parts of the desert, researchers are able to reconstruct the paleoenvironmental conditions. Specifically, fossilized hyrax dung in shallow cave shelters contains fossilized pollen and dust which contains information on the vegetation that was consumed by the hyrax. Pollen data can provide information on the vegetation during different time periods, and using this data the changes in moisture levels in desert areas such as the desert northwest of Namibia can be determined. [34]
While the pollen and dust in the dung provides information on the types of vegetation that previously existed, it is also important to use radiocarbon dating for information on the era that the dung is from. In a town in South Africa, researchers found conflicting data about the time period the dung midden they were studying was from. The initial researchers failed to consider the impact of local radiocarbon concentrations that were higher than usual due to the testing of nuclear arms. [35] Through pollen analysis, radiocarbon dating, and considering the history of radiocarbon levels in the atmosphere, dung middens are able to provide useful information about the historical environment of dry and arid places such as the Namib desert.
The rock hyrax, also called dassie, Cape hyrax, rock rabbit, and coney, is a medium-sized terrestrial mammal native to Africa and the Middle East. Commonly referred to in South Africa as the dassie, it is one of the five living species of the order Hyracoidea, and the only one in the genus Procavia. Rock hyraxes weigh 4–5 kg (8.8–11.0 lb) and have short ears.
The dorcas gazelle, also known as the ariel gazelle, is a small and common gazelle. The dorcas gazelle stands about 55–65 cm at the shoulder, with a head and body length of 90–110 cm and a weight of 15–20 kg. The numerous subspecies survive on vegetation in grassland, steppe, wadis, mountain desert and in semidesert climates of Africa and Arabia. About 35,000–40,000 exist in the wild.
The mountain gazelle, also called the true gazelle or the Palestine mountain gazelle, is a species of gazelle that is widely but unevenly distributed.
The rhim gazelle or rhim, also known as the slender-horned gazelle, African sand gazelle or Loder's gazelle, is a pale-coated gazelle with long slender horns and well adapted to desert life. It is considered an endangered species because fewer than 2500 are left in the wild. They are found in Algeria, Egypt, Tunisia and Libya, and possibly Chad, Mali, Niger, and Sudan.
The dama gazelle, also known as the addra gazelle or mhorr gazelle, is a species of gazelle. It lives in Africa, in the Sahara desert and the Sahel. A critically endangered species, it has disappeared from most of its former range due to overhunting and habitat loss, and natural populations only remain in Chad, Mali, and Niger. Its habitat includes grassland, shrubland, semi-deserts, open savanna and mountain plateaus. Its diet includes shrubs, herbs, grasses, leaves, shoots, and fruit.
Paleolimnology is a scientific sub-discipline closely related to both limnology and paleoecology. Paleolimnological studies focus on reconstructing the past environments of inland waters using the geologic record, especially with regard to events such as climatic change, eutrophication, acidification, and internal ontogenic processes.
The Arabian gazelle(Gazella arabica) is a species of gazelle from the Arabian Peninsula. There are approximately 5,000 – 7,000 mature individuals in the wild.
The steenbok is a common small antelope of southern and eastern Africa. It is sometimes known as the steinbuck or steinbok.
The Yotvata Hai-Bar Nature Reserve is a 3,000-acre (12 km2) breeding and reacclimation center administered by the Israel Nature Reserves & National Parks Authority, situated in the Southern Arava near Yotvata.
Grant's gazelle is a relatively large species of gazelle antelope, distributed from northern Tanzania to South Sudan and Ethiopia, and from the Kenyan coast to Lake Victoria. Its Swahili name is swala granti. It was named for a 19th-century British explorer, James Grant.
The southern tree hyrax, also known as the southern tree dassie, is a species of mammal in the family Procaviidae. The southern tree hyrax is mainly found in the south central eastern side of Africa.
The tree hyrax or tree dassie is a small nocturnal mammal native to Africa. Distantly related to elephants and sea cows, it comprises the four species in the genus Dendrohyrax, one of only three genera in the family Procaviidae, which is the only living family within the order Hyracoidea.
Hyraceum is the petrified and rock-like excrement composed of both urine and feces of the rock hyrax and closely related species.
The Eritrean coastal desert ecoregion is a harsh sand and gravel strip along the southern part of the coast of Eritrea and the Red Sea coast of Djibouti. This coast is of ecological importance as a channel for the mass migration of birds of prey.
The Grand Bara, Bara Wein or Bada Wein, is a desert in southern Djibouti. It consists of large areas of sand flats, with sparse, semi-desert and desert grasses and scrub vegetation. A road built in 1981 passes through the area, connecting the capital Djibouti City with the south. Prior to the arrival of the French, the extremely arid interior was inhabited primarily by the Issa Somali. Runners make their way across the Grand Bara Desert during the Annual Grand Bara 15K race.
Animal latrines are places where wildlife animals habitually defecate and urinate. Many kinds of animals are highly specific in this respect and have stereotyped routines, including approach and departure. Many of them have communal, i.e., shared, latrines.
Elands Bay Cave is located near the mouth of the Verlorenvlei estuary on the Atlantic coast of South Africa's Western Cape Province. The climate has continuously become drier since the habitation of hunter-gatherers in the Later Pleistocene. The archaeological remains recovered from previous excavations at Elands Bay Cave have been studied to help answer questions regarding the relationship of people and their landscape, the role of climate change that could have determined or influenced subsistence changes, and the impact of pastoralism and agriculture on hunter-gatherer communities.
Michael Edward MeadowsFAAS FRSSAf is a British-South African Emeritus Professor of physical geography at the Department of Environmental and Geographical Sciences, University of Cape Town.
A rock hyrax midden is a stratified accumulation of fecal pellets and a brown amber-like a urinary product known as hyraceum excreted by the rock hyrax and closely related species.
Gruta del Indio is a rock shelter located in Rincón del Atuel, Southern Mendoza, Argentina. The site is located 28 km south of the town of San Rafael at around 660m above sea level. Significant excavations suggest the coexistence of humans and mega-fauna, possibly contributing to existing theories of humans acting as major predators were large contributors to the extinction of such creatures.
Dung midden : Pile of droppings that grows through consistent returns. Used as a territory marker in connection with scent-marking.
{{cite journal}}
: CS1 maint: multiple names: authors list (link){{cite journal}}
: CS1 maint: multiple names: authors list (link)