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A brief story of sengis, or elephant shrews

Posted by Z Dental Group - June 15th, 2013

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Darren Naish is a scholarship writer, technical editor and palaeozoologist (affiliated with a University of Southampton, UK). He mostly works on Cretaceous dinosaurs and pterosaurs yet has an zealous seductiveness in all things tetrapod. His publications can be downloaded during darrennaish.wordpress.com. He has been blogging during Tetrapod Zoology given 2006. Check out a Tet Zoo podcast during tetzoo.com!

Nature Blog Network

Follow on Twitter @TetZoo.


Darren Naish is a scholarship writer, technical editor and palaeozoologist (affiliated with a University of Southampton, UK). He mostly works on Cretaceous dinosaurs and pterosaurs yet has an zealous seductiveness in all things tetrapod. His publications can be downloaded during darrennaish.wordpress.com. He has been blogging during Tetrapod Zoology given 2006. Check out a Tet Zoo podcast during tetzoo.com!

Nature Blog Network

Follow on Twitter @TetZoo.

A brief story of sengis, or elephant shrews





Zanj elephant termagant (Rhynchocyon petersi); picture by Joey-Makalintal, protected underneath a Creative Commons Attribution 2.0 Generic license.

Macroscelideans – a elephant shrews or sengis – are an exclusively African organisation of animalivorous placental mammals, famous for their long, mobile snouts [adjacent picture of a rhynchocyonine sengi by Joey Makalintal]. They have prolonged tails, proportionally lengthen limbs, and operation in distance from 10 to 30 cm, and from 50g to over 500g. Digital rebate and elongate, mostly fused, distal prong segments are in gripping with mostly saltatorial habits: sengis are rapid runners, yet also skilful during leaping when avoiding obstacles and predators. Limb bone fragments of hoary taxa are identical to a analogous tools of vital taxa and advise that hoary forms were identical in locomotor abilities. Close kin of vital class (some belonging to a same genera, such as Rhynchocyon) are famous from a Miocene onwards, with molecular time information indicating that aridification events in Africa gathering diversification events within a crown-clade (Douady et al. 2003).





Reconstructed skull of a Early Miocene myohyracine Myohyrax oswaldi (after Patterson 1965).

Paleogene macroscelideans were some-more different yet nothing are represented by generally good remains. The oldest taxa go to a Middle and Late Eocene organisation Herodotiinae, recognizable due to molariform top fourth premolars, a far-reaching mesial cingulum on a top molars and other dental characters. Herodotiines seem to be a sister-group to a clade that contains all other macroscelideans. Within this latter clade, Metoldobotes from a Oligocene seems to be sister-taxon to a Rhynchocyoninae + Myohyracinae + Macroscelidinae clade (Tabuce et al. 2001). Metoldobotes is a biggest hoary macroscelidean nonetheless reported, yet even it was usually somewhat incomparable than a biggest vital class (Patterson 1965). Metoldobotes resembles vital sengis in tooth form yet has some-more bulbous tooth cusps. Its enlarged, procumbent reduce third tooth possesses a lingual slit of different duty (to my knowledge, nobody has nonetheless suggested that it was a vicious sengi that used that slit to broach venom! Tooth grooves are widespread in mammals and other tetrapods and are frequently separate to a prolongation or participation of venom).





Lower jaw of Mylomygale spiersi from a Pleistocene of South Africa, from Patterson (1965). The find site of this citation was – according to Broom – “about half a mile to a north of a cavern that yielded a Taungs man-ape skull”.

Among a some-more engaging of hoary sengis is Mylomygale of Pliocene Africa. This taxon has large, complex, strikingly rodent-like impertinence teeth and was roughly positively a rodent-like herbivore. The Miocene myohyracines (like Myohyrax, illustrated above) were outwardly hyrax-like and were primarily suspicion to be hyraxes. Like hyraxes, their molariform teeth prove that they were browsing herbivores though, again, a biggest taxa were substantially usually somewhat incomparable than a largest vital sengis.

Traditional anatomical hypotheses associated macroscelideans with Archonta, Eulipotyphla or Glires. These due relations were always cryptic in perspective of a vaguely ‘ungulate-like’ form of macroscelidean teeth and prong skeleton (Simons et al. 1991). Their stream inclusion within Afrotheria and tighten to several Paleogene taxa traditionally personal as condylarths does make some-more sense.

For prior Tet Zoo articles on afrotherians, see…

Refs – -

Douady, C. J., Catzeflis, F., Raman, J., Springer, M. S. Stanhope, M. J. 2003. The Sahara as a vicariant agent, and a purpose of Miocene climatic events, in a diversification of a mammalian sequence Macroscelidea (elephant shrews). Proceedings of a National Academy of Sciences 100, 8325-8330.

Patterson, B. 1965. The hoary elephant shrews (family Macroscelididae). Bulletin of a Museum of Comparative Zoology, Harvard University 133, 295-335.

Simons, E. L., Holroyd, P. A. Bown, T. M. 1991. Early tertiary elephant-shrews from Egypt and a start of a Macroscelidea. Proceedings of a National Academy of Sciences 88, 9734-9737.

Tabuce, R., Coiffait, B., Coiffait, P.-E., Mahboubi, M. Jaeger, J.-J. 2001. A new classification of Macroscelidea (Mammalia) from a Eocene of Algeria: a probable start for elephant-shrews. Journal of Vertebrate Paleontology 21, 535-546.


About a Author: Darren Naish is a scholarship writer, technical editor and palaeozoologist (affiliated with a University of Southampton, UK). He mostly works on Cretaceous dinosaurs and pterosaurs yet has an zealous seductiveness in all things tetrapod. His publications can be downloaded during darrennaish.wordpress.com. He has been blogging during Tetrapod Zoology given 2006. Check out a Tet Zoo podcast during tetzoo.com!

Nature Blog Network

Follow on Twitter @TetZoo.

The views voiced are those of a author and are not indispensably those of Scientific American.


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  1. 1. llewelly 2:11 pm 06/15/2013

    Elephant shrews: More closely associated to elephants than to shrews.

    It is engaging that 3 of 6 afrotherian orders have really long, supportive noses. (The other 3 afrotherian orders also have prolonged supportive noses, yet maybe not scarcely so among mammals. )


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