Afrosoricida -- Tawny Tenrecs and Golden Moles
Origins
Afrosoricida means "looking like African shrews". The name of this order could be made a bit more exciting considering it has got 21 species of golden moles, a multitude of tenrecs and even creatures called otter shrews. However, that is neither here nor there. We do know that this group is a recently branched order that used to belong in Insectivora, among other shrews, hedgehogs and the like. Why the split then, a reader might ask? I mean tenrecs look very like hedgehogs with smaller quills, really. There are a couple of good reasons. One is that these creatures are zalambdodont(cool word, yes?). You see, we mammals are really classified according to our teeth structures and being zalambdodont really means that the upper molars have one major cusp as opposed to three in other placental mammals. So it's not really as cool as it sounds. The other major reason is that these creatures have a cloaca. All that means is that their pee and poo come out from the same place. Gross, yes ? Eww, even! However, this feature is shared by birds and reptiles so that shows this order seems to be a truly ancient group of mammals. They are said to have arisen around the Cretaceous era ( 70 million years ago) in Africa, migrated to Madagascar, and have hung in there adapting well to all the different niches that have presented themselves. The animals in this order are very closely related to aardvarks and sengis.
Physical Characteristics
Apart from the obvious cloacal opening and the teeth structure, tenrecs tend to be small animals varying from 4cm to 39 cm in length. There is no pronounced body type since they have evolved to take over the insect-eating niche in Madagascar. However, based on the niche occupied, they look like shrews, hedgehogs or otters. There coat can vary from smooth to spiny and the coloration of the fur is generally dirt brown. Most species are also nocturnaland have poor eyesight. However, their whiskers are rather senstive and they can detect very minute vibrations in the ground to locate their prey.
Geographic Distribution
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Tenrecs are an amazing example of speciation in isolated ecologial niches. Very much like the marsupials in Australia, many types of Tenrecs have colonized Madagascar and have radiated into niches occupied by rats, hedgehogs and even ant-eaters. These amazing creatures are found mostly in forest habitats but some species also inhabit arid regions in Madagascar. Their relatives, the golden moles live in the Namib desert, swimming in the sands, snacking on insects and generally having a merry old time. The only tenrecs left in mainland Africa are the otter shrews that live in the jungles of Congo and occupy the niche that an otter would.
Reproduction
Tenrecs have relatively long pregnancies(8 weeks) when compared to other insectivores like shrews(4 weeks). The size of a litter varies with each species depending on the type of climate and the lack or abundance of food. One species called the tailless tenrec can have the largest litter next to the naked mole rat. They can have upto 32 young!! Now that is one crowded nest or nursery.
Feeding Habits
This order is largely fond of insects and other invertebrates. Some of the larger species can dig into amphibians once in a while and aquatic species indulge in crayfish too. However, there is very limited specialization in eating habits otherwise.
Families within Afrosoricida
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