Kangaroos, rat

Rodent species differ in their ability to smell buried seeds those from arid climates perform better than species from mesic climates. Specifically, Panamint kangaroo rats, Dipodomys panamintinus, from arid and semiarid areas of the Great Basin Desert in North America were the only species that found deep caches... 

Ord s kangaroo rat Dipodomys ordii Green plants Injected 6-MBOA 6-MBOA on rolled barley in field Reproduces after rainfall Increased uterus mass More pregnant females Rowsemitt and O Connor, 1989... 

Randall, J. A. (1986). Preference for estrous female urine by male kangaroo rats (Dipodomys spectabilis). Journal of Mammalogy 67,736-739. 

Webster, D. B. (1973). Audition, vision, and olfaction in kangaroo rat predator avoidance. 

The metabolic water formed by oxidation of foods and stored fats is actually enough to allow some animals in very dry habitats (gerbils, kangaroo rats, camels) to survive for extended periods without drinking water. 

Desert rodents lead the most water-independent life of all vertebrates. Kangaroo rats can so reduce their evaporation that they are able to maintain water balance on only metabolic water. Other species survive on only meiabolic water plus free water in air-dry seeds. Respiratory water loss is reduced by cool nasal mucosal surfaces, which condense water from warm air coming from the lungs, before it can be expired. Skin impermeability involves a physical vapor barrier in the epidermis, pins unknown physiological factors. 

Sounds produced by humans can also interfere with the ability of animals to communicate. Such interference can inhibit an animaPs ability to protect itself, to find food, and to live a normal life. For example, ships emit low-frequency sounds that interfere with whale communications. Other human noises can frighten whales away from their normal migration routes. In the desert, kangaroo rats Dipodomys spp.) exposed to the roar of a dune buggy lose their ability to hear snakes approaching. Japanese quail (Coturnix Coturnix Japonicd) have to call much louder than usual when they live in a noisy environment. Sooty terns (Sterna fuse at a) have been observed to abandon their nests when jets create sonic booms. Intense bursts of noise have also caused condors (Gymnogyps californianus) to abandon their nests. 

Reynolds, H. G. and Glendening, G. E. (1949). Merriam kangaroo rat as a factor in mesquite propagation on southern Arizona rangelands. /. Roio c Manage. 2, 193- 197. 

Mazrimas J.A. and Hatch F. T. (1972). A possible relationship between satellite DNA and the evolution of kangaroo rat species (genus Dipodomys). Nature New Biol. 240 102-105. 

Krutch, J. W. The Voice of the Desert. New York Morrow, 1975. [Chapter 7, The Mouse That Never Drinks, is a description, primarily from a naturalist s point of view, of the kangaroo rat, but it does make the point that metabolic water is this animal s only source of water.]... 

A kangaroo rat converts some of its waste nitrogen to uric acid. 

These animals do not make urea rather, they convert all their waste nitrogen to uric acid (Figure 23.17), the concentrated white solid so familiar in bird droppings. Some desert mammals, such as the kangaroo rat, which never drinks water but rather lives off metabolic water, also convert some of their waste nitrogen to uric acid to conserve the water used in urine. 

Paglia D. 1968. Hematopathologic surveys of kangaroo rats (Dipodomys microps) populating plutonium contaminated regions of the Nevada test site. Health Phys 15 493-498. 

Brown Norway rat, Rattus norvegicus, 337 Cotton rat, Sigmodon hispidus, 692 Desert woodrat, Neotoma lepida, 803 Heermann s kangaroo rat, Dipodomys heermanni, 803... 

Kangaroo rat, Dipodomys spp., 786, 803,806 Laboratory white rat, Rattus sp., 194, 275, 280, 288, 555, 566, 643, 864, 885 Morrow Bay kangaroo rat, Dipodomys heermanni morroensis, 806 Roof rat, Rattus rattus, 693,694 Rhinoceros, black, Diceros bicornis, 744 Rockchuck, Ochotona spp., 211... 

Comment An average adult ingests 2 L of water daily and eliminates 2.4 L. The extra 0.4 L is produced in the metabolism of foodstuffs, such as oxidation of glucose. The desert rat (kangaroo rat), on the other hand, apparently never drinks water. It survives on its metabolic water. 

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