Common mole rat (Cryptomys hottentotus)

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African animals, Molerats, Bathyergidae, Cryptomys hottentotus, Common mole rat

Scientific Name: Cryptomys hottentotus
Common Name: Common mole rat
Distribution: Common mole rats are found in south-western Cape Province of South Africa.
Description: The fur is thick and is composed of many different colours, including a white spot on the head. Many of the physical features of mole rats are suited to an underground lifestyle. The body is cylindrical and the appendages are short. This shape allows the animal to burrow effectively. Long sensory hairs called vibrissae stand out from the pelage over the body. Mole rats have chisel-like incisors used for digging. The eyes are very reduced.
Difference in Sex:  In each colony, the reproductive male and female are the largest individuals. The rest of the colony members exhibit a sexually dimorphic pattern of size where the males are larger than the females.
Average Weight: 50 to 130 g.
Habitat: Common mole rats live in the soil of grassy open plains.
Habits: Common mole rats live an entirely subterranean life. They dig extensive tunnel systems, one tunnel system, which contained 10 adult and 3 young, measured 1 km in length. The tunnels are dug mostly through compact soils but occasionally sandy soil is used. The tunnel systems are primarily a product of the search for food, but they also provide sites for food storage, nesting and waste disposal.
Common mole rats are social creatures, living in family units of up to 14 individuals. Each colony has one reproductive pair, which are usually the largest female and male in the group. The other individuals in the group are workers. The creation of a caste system of workers and reproducers is an example of asocial animal behaviour. The dominance hierarchy in a common mole rat colony is described as linear. The breeding male is at the top of the hierarchy, followed by the breeding female. For the rest of the colony males are dominant to females, and dominance is related to body mass.
The worker category is divided into two groups of animals, the "workers" and the "casual workers". The worker group usually consists of smaller sized mole rats that have been newly recruited to the colony. These mole rats do 15-20% more work than the second group, the casual workers. The casual worker group is comprised of larger, older mole rats.
Main feeding time:
Size: Body length of common mole rats ranges from 10.5 to 16.5 cm long and tail length from 1.2 to 3.8 cm.
Number of young at birth: 2-5 young, each weighing 8-9 grams.
Diet: Common mole rats are herbivorous, eating mainly geophytes, plants with underground storage organs, and grass rhizomes. They also consume large quantities of fibres, found in the roots of many plants.
Interesting facts: