The mule is the offspring of a male donkey
(jackass) and a female horse (mare). The opposite
cross-a female donkey (jenny) bred to a male
horse (stallion)-produces a hinny. A mule has a
donkey's large head and long ears, the body of a
horse, and an asslike tail. Its voice is a bray that is
somewhat different than that of the
ass. Some mules are quite large: as
much as sixteen hands (sixty-four
inches) at the withers.
Mules are strong and durable.
They are more surefooted and can
bear heavier loads than either the
horse or the donkey. This is a good example
of hybrid vigor or heterosis: the
tendency of hybrids to be larger and
more durable than their parent species.
It is often said that a mule is
smarter than a horse because a horse
may overeat and "lounder" (become
ill fromovereating) if given unlimited
access to grain, but a mule will not.
Mules are almost always infertile, apparently
due to differing numbers of
chromosomes in the gametes of the
horse and the donkey.
Mules in History
Mules were essential in transport for at least three thousand years, from ancient times until the invention of the steam engine and the building of railroads. Mules can be ridden but were used mostly in mule teams or mule trains to pull wheeled vehicles in both peace and war. For example, the twenty-mule teams of Death Valley, California, hauled two wagons loaded with borax plus a water wagon with a combined weight of over twenty-seven tons. Wild populations of equids have been greatly reduced by humans through hunting and habitat destruction, some to the point of extinction. Domestic horses, donkeys, and mules, however, have thrived for thousands of years in association with humankind. Despite being largely replaced by mechanical power, domestic equids are still common.
Family: Equidae (horses)
Genus and species: E.asinus bred with Equus caballus
Geographical location: Mules were introduced to wide areas of Europe, Asia, Africa, and later to both North and South America
Habitat: Mules are well-adapted to hot, dry deserts
Gestational period: 11.5 months
Life span: Twenty to twenty-five years on average
Special anatomy: Long ears dissipate heat; broad single toe (hoof) on each foot is an adaptation for running; capable of digesting large quantities of low-protein fodder
Copyright © 2014 Animalia Life | All rights reserved