There are two families in the Order Lagomorpha - the hare-shaped animals:
- Family Leporidae: the 58 species of rabbits and hares in 11 genera
occur in a wide range of habitats - woods, forests, swamps, deserts,
mountains, grass-lands, the snow-covered artic and, most importantly
agricultural lands - throughout the world.
- Family Ochotonidae: the 29 species of guinea pig-like,
pikas belonging to the genus Ochotona live in rocks in mountainous areas and in burrows
in alpine meadows, steppes or semi-desert in Central Asia, China
and Western North America.
Lagomorphs have long, soft fur. Their ears are large, and eyes are set high on their heads, giving them a wide field of vision. The neck is weak but flexible, allowing them to turn their heads more than rodents.
Lagomorphs are no more closely related to rodents than to any other Order
of Mammals, in spite of certain marked similarities
in their dentition and diet.
|All lagomorphs are herbivores living mostly on grasses. Their cheek
teeth are adapted for grinding their abrasive food and they have two pairs
of characteristic incisors:|
- a front pair of continuously growing, functional incisors
- a second pair of peg-like, non-functional, incisors.
The dental formula of rabbits and hares is: I2/1; C0/0; P3/2; M3/3.
The dental formula of pikas is: I2/1; C0/0; P3/2; M2/3.
All have a diastema between the incisors and cheek teeth.
Lagomorphs have special adaptations to help obtain nutrients from a
diet comprising large quantities of grasses.
- Bacteria in the caecum, a large blind sac between the small
and large intestines, help digest cellulose.
- Some nutrients produced by digestion in the
caecum are absorbed into the blood stream.
- Other nutrients, e.g. vitamin B12, cannot
be absorbed and are passed out in the soft, black viscuous
- The caecal pellets are eaten directly
from the anus and mixed with
other food in the stomach.
- The nutrients the pellets contain
are absorbed as the food passes through the gut for the second time.
- Waste from food digested in the small intestine turns into
hard pellets, that are not eaten.
- Lagomorphs have only one opening - the cloaca - for both the anus and the urnio genital tract.
We have specimens of the European rabbit and European hare. Although these
European lagomorphs are not under threat, many less well known rabbits
and hares are threatened due to the destruction of their habitats.
Both rabbits and hares have long-limbs, especially hares, and are adapted to moving
rapidly over open ground. They have long ears, an elongated nasal region,
and a white underside to the tail. Although physically rather similar,
the two groups have some very marked differences in behaviour,
physiology and reproductive strategies. Rabbits are varied and classified into 10 genera; hares are
classed together in the genus Lepus.
- Rabbits run for cover when threatened.
- Young rabbits, or kittens, are altricial: they are born naked or with little fur,
blind and helpless.
- The kittens are kept in nests, within burrows or dense cover.
- Mother rabbits only visit their young to feed them once every 24 hours; sealing
the nests in between visits to protect the young from predators.
- Hares lie up in scrapes or forms in open country; when disturbed, they run away from danger.
- Young hares or leverets are precocial: they are born at an advanced stage,
with fur, open eyes and well co-ordinated movements.
- Hares give birth in a nest, but the leverets young soon scatter,
hiding during the day and only coming together for a short period at dusk
to take a hurried meal of milk
from their mother.
RABBITS AND HARES
Both rabbits and hares are solitary creatures for the most part.
The sociable nature of the European rabbit, which lives in stable territorial
groups in burrows in warrens, is exceptional. Only a few other rabbit
species dig burrows; others use burrows made by other mammalian species.
Rabbits and hares are major sources of food for carnivorous mammals
and birds and have a number of adaptations to ensure
they maintain large populations. They reach sexual maturity early
and the females
- have short gestation periods and large litters;
- their eggs are shed in response to copulation (not cyclically);
- can conceive immediately they have given birth.
Although highly successful reproductive strategies have turned
some species, including the European rabbit, into significant agricultural
pests, lagomorphs, especially the European rabbit, have proved very
useful to humans for food and fur.