Ducker
Ducker | ||||||||||||
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Blue duiker ( Philantomba monticola ) |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Cephalophini | ||||||||||||
Blyth , 1863 |
The duikers (Cephalophini; common in southern Africa known as duikers ) are a tribe of horn-bearers native to Africa . They are small, forest-dwelling antelopes . Although they are largely unknown, they are a very biodiverse taxon .
features
The smallest species are no larger than a hare, but the largest can be larger than a deer . The length of the head body varies between 60 and 170 cm, the shoulder height between 40 and 80 cm, and the weight between 3.5 and 80 kg, depending on the species. The tail measures about 5 to 10 cm. The coloration varies between species. Often the top is colored in a shade of brown, while the bottom is significantly lighter. Some species have yellowish or reddish shimmering fur, and the zebra sugar has a zebra-like stripe pattern. Both sexes (genus Cephalophus ) or only the males (genera Philantomba and Sylvicapra ) have horns. These start a little further back and are short and directed backwards. In some species they are completely covered by the hair on the head. There is a clearly thickened frontal bone on the skull , which is partly ossified and serves as a ram. In addition, the brain skull is greatly enlarged compared to other bovids.
distribution
All species live in Africa south of the Sahara, and here mostly in the tropical rainforests of West and Central Africa. Here they lead such a hidden way of life that new, previously unknown species are still being discovered. Those species that do not live in the rainforest also seek protection from thick bushes. You never see Ducker in the open savannah. Some species can be found in the mountains up to an altitude of 3500 m.
Way of life
The low level of awareness of the duikers is certainly due to the fact that they can hardly be observed in the wild, as they are mainly nocturnal, always stay in the area of as dense, impassable tangle of plants as possible and are also very shy. At the slightest disturbance, they flee through the undergrowth. Her name, which is derived from the Afrikaans word duiker and means " duiker ", is also related to this.
The food is grass, leaves, fruits, tubers and flowers. At least the crown duiker has been observed to occasionally eat insects, frogs, small birds, mice and carrion; other species are believed to behave in the same way, which is quite unusual for a ruminant.
Duckers live solitary or in pairs. Both males and females behave very aggressively towards their peers. On the borders of the own districts there are often fights that are fought with the little horns. The females give birth to a single young after a gestation period of 120 days.
Systematics
Internal systematics of the duiker according to Johnston et al. 2012
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There are currently 41 known species, which are divided into three genera:
- Tribus Cephalophini Blyth , 1863
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- Genus Sylvicapra Ogilby , 1837
- Senegalese duiker ( Sylvicapra coronata ( Gray , 1842))
- Crown duiker ( Sylvicapra grimmia ( Linnaeus , 1758))
- Sahel crown duiker ( Sylvicapra pallidor Schwarz , 1914)
- Genus Philantomba Blyth , 1840
- East Africa blue duiker ( Philantomba aequatorialis ( Matschie , 1892))
- Angola blue duiker ( Philantomba anchietae ( Bocage , 1879))
- Zimbabwean blue duiker ( Philantomba bicolor ( Gray , 1863))
- Congo blue duiker ( Philantomba congica ( Lönnberg , 1908))
- Malawi blue duiker ( Philantomba hecki ( Matschie , 1897))
- Zambia blue duiker ( Philantomba defriesi ( Rothschild , 1904))
- Tanzanian blue duiker ( Philantomba lugens ( Thomas , 1898))
- Maxwell duiker ( Philantomba maxwelli ( CH Smith , 1827))
- Bioko blue duiker ( Philantomba melanorhea ( Gray , 1846))
- Blue duiker or Cape blue duiker ( Philantomba monticola ( Thunberg , 1789))
- Simpson's blue duiker ( Philantomba simpsoni ( Thomas , 1910))
- Verheyen-Ducker ( Philantomba walteri Colyn, Hulselmans, Sonet, Oudé, De Winter, Natta, Nagy & Verheyen , 2010)
- Genus Cephalophus C. H. Smith , 1827
- Zanzibar duiker ( Cephalophus adersi Thomas , 1918)
- Uëlle white-bellied duiker ( Cephalophus arrheni Lönnberg , 1917)
- Brooke duiker ( Cephalophus brookei Thomas , 1903)
- Petersducker ( Cephalophus callipygus Peters , 1876)
- Congo black- backed duiker ( Cephalophus castaneus Thomas , 1892)
- White-legged thickener ( Cephalophus crusalbum Grubb , 1978)
- Eastern yellow-bridged duiker ( Cephalophus curticeps Grubb & Groves , 2001)
- Black- backed duiker ( Cephalophus dorsalis gray , 1846)
- Elgon black- fronted duiker ( Cephalophus forsteri St. Leger , 1934)
- Harvey's red duiker ( Cephalophus harveyi ( Thomas , 1893))
- Kenyan black- forehead duiker ( Cephalophus hooki St. Leger , 1934)
- Itombwe black- fronted duiker ( Cephalophus hypoxanthus Grubb & Groves , 2001)
- Jentink duiker ( Cephalophus jentinki Thomas , 1892)
- Johnston Ducker ( Cephalophus johnstoni Thomas , 1901)
- Lestrade duiker ( Cephalophus lestradei Grubb & Groves , 1974)
- White-bellied duiker ( Cephalophus leucogaster Gray , 1873)
- Natal red duiker ( Cephalophus natalensis A. Smith , 1834)
- Black duiker ( Cephalophus niger gray , 1846)
- Black- fronted Thucker ( Cephalophus nigrifrons Gray , 1871)
- Ogilby Ducker or Fernando Po Ducker ( Cephalophus ogilbyi ( Waterhouse , 1838))
- Ruwenzori black- forehead duiker or Ruwenzoriducker ( Cephalophus rubidus Thomas , 1901)
- Red-flanked duiker ( Cephalophus rufilatus Gray , 1846)
- Yellow-bridged duiker ( Cephalophus silvicultor ( Afzelius , 1815))
- Abbott duiker ( Cephalophus spadix true , 1890)
- Weyns duiker ( Cephalophus weynsi Thomas , 1901)
- Zebra sugar ( Cephalophus zebra ( Gray , 1838))
The systematics of the duiker is complex and not undisputed among zoologists. The genus Philantomba , which includes the very small blue duiker, was partially listed as a subgenus of Cephalophus . Peter Grubb and Colin Peter Groves then recognized Philantomba as independent in a study in 2001 and, according to their morphological investigations, placed the genus next to Sylvicapra . At the same time a molecular genetic analysis was published in which Philantomba formed the sister group to Cephalophus - Sylvicapra , which supported Philantomba's own genus character regardless of the exact phylogenetic position . The study also found three lines of development within Cephalophus . The first includes the giant duiker, which includes the jentink duiker ( Cephalophus jentinki ) and the black- backed duiker ( Cephalophus dorsalis ), the second is the West African red duiker with the St. Peter's duiker ( Cephalophus callipygus ) and the ogilby duiker ( Cephalophus ogilbyi ) and the third, the East African red duiker, such as the natal red duiker ( Cephalophus natalensis ) and the black forehead duiker ( Cephalophus nigrifrons ). Another genetic study from 2012 largely confirmed this result. However, she also showed that neither the Zanzibar duiker ( Cephalophus adersi ) nor the zebra duiker ( Cephalophus zebra ) can be precisely assigned to one of these three groups. As a further result, Sylvicapra turned out to be the sister group of the giant duikers and thus embedded more deeply in the genus Cephalophus than originally assumed, whereby the latter is to be regarded as paraphyletic . As a result, it is discussed whether the various red duiker species should be excluded from Cephalophus ; Cephalophorus was proposed as an alternative genus name for them . Leucocephalophus is also being discussed as a new genus for the Zanzibar duiker and Cephalophula for the zebra duiker. The general family relationships of the duikers identified in the work in 2001 and 2012 are supported by another genetic analysis from 2019.
How the duikers stand in the horn-bearer system has long been a matter of debate. It used to be common practice to put the duiker at the beginning of a horn-bearer system; as they were believed to be very similar to the earliest horn-bearers of the Miocene , they were considered a very original branch. Later, in 1992, Alan W. Gentry referred her to the side of the cattle (Bovinae) on the basis of morphological investigations , while others assumed an intermediary position between the Bovinae and the Antilopinae . First genetic studies revealed a close relationship to the Reduncini , so the reedbuck ( Redunca ) and waterbuck ( Kobus ), as well as a close position to the was hartebeest (Alcelaphini) proposed. More recent molecular genetic studies group the duiker together with the clip jumpers (Oreotragini) and the small ram ( Neotragus ). The reason for the sometimes very different assignments is the numerous similarities and deviations of the duikers with regard to their genes and anatomy.
Tribal history
From a phylogenetic point of view, the duikers are relatively young. The molecular genetic studies suggest that it originated in the Upper Miocene , which is consistent with the development of other forest-dwelling hornbeams, such as the bushbuck . The genus Philantomba split off from the trunk line around 7.55 million years ago, and the division into the giant duiker and Sylvicapra took place around half a million years later. The separation of the East and West African red duikers did not occur until the Pliocene , about 3.53 million years ago. The strong diversification of the red duiker, but also of the other lines, is possibly a result of the frequently changing climatic conditions in the subsequent Pleistocene . During the cold maxima of the Ice Ages, drier conditions prevailed in Africa, as a result of which open landscapes expanded and the forests were pushed back. The closed forest belt in West and Central Africa frayed and individual populations were isolated. This ultimately led to allopatric speciation.
Duckers' fossil records are relatively rare. Individual isolated teeth and mandibular fragments come from Laetoli in Tanzania. A horn cone was also reported, but it could also belong to another antelope form. The finds are almost four million years old. Further finds came to light in Koobi Fora in Kenya and are at the transition from the Pliocene to the Pleistocene. In addition, some remains were recovered in Makapansgat in South Africa, including individual mandibular fragments and a horn cone. Another upper jaw fragment was registered from Taung , also South Africa. Both sites show a similar age in the transition from the Pliocene to the Pleistocene. All finds so far have been made for the genus Cepahlophus .
Threat and protection
Although the yellow-bridged duiker, the Maxwell's duiker, the black-backed duiker and the red-flanked duiker are currently still very widespread, their populations continue to decline in most areas of their distribution areas. This is due to the deforestation of tropical forests, which significantly reduces the duiker's habitat. Although most duikers can survive in the forest-like secondary vegetation, there is hunting pressure on wild animals, not least because the tender meat of the duiker is valued as a food. By contrast, they are spared from recreational and trophy hunters.
The IUCN lists the Zanzibar duiker as critically endangered and the Jentink duiker, Abbot duiker, and zebra duiker as critically endangered or endangered.
literature
- Colin Groves and Peter Grubb: Ungulate Taxonomy. Johns Hopkins University Press, 2011, pp. 1–317 (SS 108–280)
- Colin P. Groves and David M. Leslie Jr .: Family Bovidae (Hollow-horned Ruminants). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 2: Hooved Mammals. Lynx Edicions, Barcelona 2011, ISBN 978-84-96553-77-4 , pp. 751-774
- Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (Eds.): Mammals of Africa Volume VI. Pigs, Hippopotamuses, Chevrotain, Giraffes, Deer and Bovids. Bloomsbury, London, 2013, pp. 220-301
- Ronald M. Nowak: Walker's Mammals of the World. 2 volumes. 6th edition. Johns Hopkins University Press, Baltimore MD et al. 1999, ISBN 0-8018-5789-9 .
- Don E. Wilson, DeeAnn M. Reeder (Eds.): Mammal Species of the World. A Taxonomic and Geographic Reference. 2 volumes. 3rd edition. Johns Hopkins University Press, Baltimore MD et al. 2005, ISBN 0-8018-8221-4 .
Individual evidence
- ↑ a b Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume VI. Pigs, Hippopotamuses, Chevrotain, Giraffes, Deer and Bovids. Bloomsbury, London, 2013, pp. 220-301
- ^ A b c Anne R. Johnston and Nicola M. Anthony: A multi-locus species phylogeny of African forest duikers in the subfamily Cephalophinae: evidence for a recent radiation in the Pleistocene. BMC Evolutionary Biology, 12, 2012, p. 120 ( [1] )
- ↑ Colin P. Groves , David M. Leslie Jr .: Family Bovidae (Hollwow-horned Ruminants). In: Don E. Wilson, Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 2: Hooved Mammals. Lynx Edicions, Barcelona 2011, ISBN 978-84-96553-77-4 , pp. 751-774.
- ↑ Bettine Jansen van Vuuren and Terence J. Robinson: Retrieval of Four Adaptive Lineages in Duiker Antelope: Evidence from Mitochondrial DNA Sequences and Fluorescence in Situ Hybridization. Molecular Phylogenetics and Evolution 20 (3), 2001, pp. 409-425
- ↑ a b Alexandre Hassanin, Frédéric Delsuc, Anne Ropiquet, Catrin Hammer, Bettine Jansen van Vuuren, Conrad Matthee, Manuel Ruiz-Garcia, François Catzeflis, Veronika Areskoug, Trung Thanh Nguyen and Arnaud Couloux: Pattern and timing of diversification of Cetartiodactyla (Mammalia , Laurasiatheria), as revealed by a comprehensive analysis of mitochondrial genomes. Comptes Rendus Palevol 335, 2012, pp. 32-50
- ^ Colin Groves: Current taxonomy and diversity of crown ruminants above the species level. Zitteliana B 32, 2014, pp. 5-14
- ↑ Taghi Ghassemi-Khademi and Kordiyeh Hamidi: Re-evaluation of Molecular Phylogeny of the Subfamily Cephalophinae (Bovidae: Artiodactyla); with Notes on Diversification of Body Size. Jordan Journal of Biological Sciences 12 (5), 2019, pp. 637-647
- ^ Alan W. Gentry: The subfamilies and tribes of the family Bovidae. Mammal Review 22 (1), 1992, pp. 1-32
- ^ Maria V. Kuznetsova and Marina V. Kholodova: Molecular Support for the Placement of Saigaand Procaprain Antilopinae (Artiodactyla, Bovidae). Journal of Mammalian Evolution 9 (4), 2002, pp. 271-280
- ↑ Manuel Hernández Fernández and Elisabeth S. Vrba: A complete estimate of the phylogenetic relationships in Ruminantia: a dated species-level supertree of the extant ruminants. Biological Review 80, 2005, pp. 269-302
- ↑ Fayasal Bibi: A multi-calibrated mitochondrial phylogeny of extant Bovidae (Artiodactyla, Ruminantia) and the importance of the fossil record to systematics. BMC Evolutionary Biology 13, 2013, p. 166
- ^ Eva V. Bärmann and Tim Schikora: The polyphyly of Neotragus - Results from genetic and morphometric analyzes. Mammalian Biology 79, 2014, pp. 283-286
- ↑ Yoshan Moodley and Michael W. Bruford: Molecular Biogeography: Towards an Integrated Framework for Conserving Pan-African Biodiversity. PlosOne 5, 2007, p. E454 ( [2] )
- ^ Alan W. Gentry: Bovidae. In: Terry Harrison (Ed.): Paleontology and Geology of Laetoli: Human Evolution in Context: Volume 2: Fossil Hominins and the Associated Fauna. Springer Science, 2011, pp. 363-465
- ^ LH Wells and HBS Cooke: Fossil Bovidae from the limeworks quarry Makapansgat, Potgietersrus. Palaeontologia Africana 4, 1956, pp. 1-55
- ^ Robert Broom: On the fossil remains associated with Australorpithecus Africanus. South African Journal of Science 31, 1934, pp. 471-480
- ^ Alan W. Gentry: Bovidae. In: Lars Werdelin and William Joseph Sanders (eds.): Cenozoic Mammals of Africa. University of California Press, Berkeley, Los Angeles, London, 2010, pp. 741-796