Dormouse

A dormouse is a small rodent belonging to the family Gliridae.

These animals live in Africa, Asia, and Europe. They are mostly nocturnal, which means they are active at night. Most species are arboreal and are very good at climbing trees. They have excellent hearing and use various vocalizations to signal to one another. Dormice are omnivores that eat berries, flowers, fruits, insects, and nuts. They are unique among rodents because they lack a cecum. A cecum is a part of the gut used by other species to ferment vegetable matter.

One of the most famous traits of the dormouse is its hibernation. This is a long period of dormant sleep. In temperate zones, dormice can hibernate for six months or even longer. This happens if the weather does not become warm enough to wake them. To prepare for this, they accumulate body fat during the summer. This fat provides the nourishment they need to survive the long sleep. Sometimes, they wake up for brief periods to eat food they stored nearby.

There are 28 living species of dormice today. These species are divided into nine different genera. About half of these living species belong to the African genus Graphiurus. Most dormice are quite small in size. Their bodies usually measure between 7 and 20 centimeters in length. Their weight typically ranges from 30 to 150 grams. In the wild, these animals can live for as long as five years.

The life cycle of a dormouse begins with small, helpless young. They are born without hair and are quite vulnerable. Their eyes do not open until about 18 days after they are born. Dormice generally breed once or sometimes twice each year. A typical litter contains an average of four young. The gestation period, or the time the mother carries the young, lasts 22 to 24 days. Most dormice become sexually mature after they finish their first hibernation.

History shows that dormice have been around for millions of years. The earliest known genus is Eogliravus, which lived in France during the Early Eocene. This was approximately 48 to 41 million years ago. Dormice were uniform during the Eocene but diversified during the Oligocene. This was between 34 and 23 million years ago. Their ability to hibernate may have emerged during this specific time. By the late Early Miocene, about 17 million years ago, they reached an apex of diversity. At that time, there were 18 genera and 36 species in Europe alone.

During the Miocene, dormice were the dominant group of rodents in Europe. As time passed, their diversity began a continual decline. However, there was a new period of speciation during the middle Pliocene. This was largely driven by the diversification of the African genus Graphiurus. Some dormice even experienced insular gigantism. This happened when they were isolated on Mediterranean islands during the Pliocene and Pleistocene. The largest of these was the genus Leithia from Sicily and Malta. These extinct dormice were as large as a rabbit.

Humans have had many interesting relationships with these rodents. In ancient Rome, the edible dormouse was considered a delicacy. Romans ate them as savory appetizers or as desserts with honey and poppy seeds. They even used a special enclosure called a glirarium to raise and fatten them. In modern times, some people in Slovenia and Croatia still view them as a delicacy. During the Elizabethan era, people believed dormouse fat could induce sleep. Today, some people keep them as exotic pets. The woodland dormouse is the most common species in the pet trade.

Taxonomists classify the Gliridae family into three subfamilies. These include Glirinae, Graphiurinae, and Leithiinae. The Glirinae subfamily includes the Japanese dormouse and the European edible dormouse. The Graphiurinae subfamily contains the African dormice. The Leithiinae subfamily includes groups like the garden dormice and the Chinese dormouse. Understanding these classifications helps scientists track how these small animals have changed over millions of years.