Elephant shrews were once considered to be part of the mammalian order Insectivora but were separated into their own order, the Macroscelidea, because they have several important anatomical differences from normal insectivores that indicate they are not closely related at all. Elephant shrews get their common name from their elongated, trunk-like snouts. However because they are not related to shrews, many biologists are now calling them Sengi instead, which is the Bantu word for their kind. They are small animals, ranging from mouse to rat size and all fifteen described species are endemic to Africa. They have long hind legs which enable them to jump kangaroo-like when they are disturbed. They live on a diet of insects and are usually active at dusk and dawn (crepuscular) although the Giant sengi (weighing in at a massive half a kilo) is diurnal.
Sengi belong to an ancient group of animals that evolved in Africa long before the ‘typical’ African wlldlife, such as lions, zebras, antelope and wildebeast made their appearance. One hundred million years ago, the Afrotheria, were the dominant mammalian life forms in Africa and were evolving into a strange variety of animals that superficially look nothing at all alike: elephants and hyraxes, sea cows and dugongs, sengi and aardvaarks, tenrecs and golden moles.Tenrecs made it to Madagascar, elephants made it to India and beyond, while dugongs and sea cows eventually migrated as far away as Australia and the Americas. But the Sengi never left Africa. Eventually the dominance of the African landscape passed to the newcomers who arrived from Eurasia about 25 million years ago: the eutherian carnivora and ungulates. Although reduced in diversity by the competition, the elephants, hyraxes and sengi remained. Today only about 80 species of Afrotherians survive worldwide: 3 species of elephants, four species of dugongs, one aardvaark, six hyraxes, 15 sengis, 21 golden-moles, and 30 tenrecs have been described by science.
Sengi are monogamous and the pair defend their territory vigorously: the female chasing away other females while the male chases away other males. They recognise each other by smell which is their primary sense although they also have large eyes and ears. The female makes a nest for her young which she raises on her own. They mark their territories with scent glands and as well as sniffing out these scents, they use their noses to search for such prey as spiders, ants and termites, crickets, worms and other invertebrates.
Sengi live in a wide variety of African habitats but are not found in the Sahara or the West African rainforests. The most vulnerable species is the black and rufous giant elephant shrew which is found in the forests of Tanzania and Kenya. These forests are being cut down for human habitation and farms and this is severely reducing the habitat for this species. Other sengi are also becoming less common due to human-caused habitat destruction. These are small species but because of their uniqueness and their connections to the Ancient Afrotheria, they should be conserved just as much as their vulnerable cousins, the elephants, aardvaarks, hyraxes and dugongs. It would be a shame to lose these animals that have survived for so long because of the activities of humans.
References
http://www.angelfire.com/mo2/animals1/mammal/elephantshrew.html
http://www.biodiversityexplorer.org/mammals/macroscelidea/index.htm
http://nationalzoo.si.edu/Animals/SmallMammals/fact-elephantshrew.cfm
