subterranian life

LIFE BELOW: SUBTERRANEAN MAMMALS AND INSECTS
What do all these animals have in common? They all spend a significant part of their lives underground.
Did you know that more organisms live below the ground than above?
All these animals and insects have evolved special adaptations for living underground
Natural Encounters Animal ExhibitsThere are many species of animals such a ground squirrels, chipmunks, marmots, burrowing owls, shrews, kit fox, and prairie dogs that have burrows underground, but these mammals spend nearly their entire lives underground living in tunnels and chambers they have constructed to fit their special needs
Naked Mole RatsThey are short – they are ugly – and they are totally naked! Well, not totally naked. Naked mole rats actually have tiny hairs on their feet as well as “whiskers” on their face. This mammal is unusual in that their body temperature changes with their surroundings. They do not create enough heat or have enough fat to maintain a constant body temperature.
Live in a eusocial system just like bees and termites. This means they live in a group with one breeding female called the queen and a breeding male. The colony then has individuals that have very special roles such as workers which help gather the food, care for the young, and dig the tunnels and defend the burrows
Naked mole rats have the strongest jaw muscle for a mammal their size
Their small eyes are nearly sightless, but their hearing is excellent, as is their sense of smell
Diet consists of underground parts of plants and tubers
They obtain all the water they need through their food and do not drink
They practice coprophagy, which means they reingest their feces, which allows them to maximize their uptake of nutrients from their food
A queen can produce a litter every 80 days! Each litter can contain as many as 15 pups with a maximum of 27! This is the largest average litter size for any known mammal
Naked mole rats are found in Africa in parts of Kenya, Ethiopia, and Somalia
Damaraland Mole Rats
This species is one of the largest truly subterranean mammals, although the dune mole rat of South Africa can be nearly twice as large as the damaralands
The damaraland mole rats eusocial system does not go the extremes of the naked mole rats whose system is made up of a queen, breeding males, workers, and soldiers much like that of an ant colony. These colonies do have a breeding male and female but when a colony becomes too large, individuals will leave the group to begin colonies in other areas
Damaraland mole rats occur in the African countries of Zambia, western Zimbabawe, Botswana, and Namibia
They seem to locate their food simply by “blind luck” within their tunnels by stumbling across it. This is only beneficial to colonial animals, which have more members out searching for food
Due to their poor eyesight, they can sense vibrations and air currents within the tunnels. With the addition of an excellent sense of smell, this helps them safely move through their tunnel systems which also include, food, nesting, and latrine chambers
Many insect societies live underground, coming to the surface to forage for food.
Honey-pot AntsThey are adapted to arid areas of the world where rainfall is unpredictable. During times of abundance, workers, called repletes, can act as living food jars by clinging to the ceilings of underground cavities and storing honey in their abdomens. These repletes will swell into berry-like spheres up to eight times their body weight. When food is scarce, the repletes can regurgitate the honey back to workers in the colony to sustain them until the next rain.
Further reading for both children and adults:
The Naked Mole Rat Mystery: Scientific Sleuths at Work by Gail Jarrow and Paul Sherman. 1996 Lerner Publications
The Biology of the Naked Mole rat by Paul Sherman and Jennifer Jarvis. 1991 Princeton University Press
African Mole Rats: Ecology and Eusociality by Nigel Bennett and Chris Faulkes. 2000 Cambridge University Press