Flying squirrel

Assapan ( Glaucomys volans )

The Flying Squirrel ( Pteromyini ) are a tribe of squirrels ( Sciuridae ). Between their front and hind legs, a sliding skin that acts like a paraglider when they jump from one branch spans. Although they can not really fly, they are also called flying squirrels.

Features

The sliding skin is stretched to the wrist by a crescent-shaped bone; from here it goes to the ankle of the hind leg. The tail is always long, broad and bushy and serves as a control. In this way, flying squirrel distances up to 50 m can travel. The Riesengleithörnchen in individual cases and under favorable conditions even 450 m were measured. Before landing, flying squirrels turn their body axis, so that they are perpendicular to the ground and slow down with the help of spread wide sliding skin. With wide curved body and tail abstehendem the flying squirrel land with all fours on the pad, which is their goal. Flying squirrels can change with the help of her tail even in flight direction.

The gliding has evolved several times independently among mammals. There are other groups slippery animals that are not related to the flying squirrel. These animals have developed in convergent evolution very similar lifestyles as the flying squirrel include the gliders, the Zwerggleitbeutler that Riesengleitbeutler, the giant gliders and mandrel tail squirrel.

All flying squirrels have sharp claws that enable them to secure climbing. They have five toes on the front feet and four on the hind legs. The head is round and not pointed. The large eyes are evidence of the nocturnal lifestyle.

Way of life

Flying squirrels are forest dwellers. You meet them never in open landscapes, as they could not take advantage of their gliding here. Mostly they are crepuscular and nocturnal. They climb quickly in the trees, but can perform no long jumps as the tree squirrels; and on the ground they are very awkward, since the sliding skin hindered in the movements. The food is, as with other squirrels with nuts and fruits, by the way insects are eaten.

A nest is usually built occasionally in a tree hollow, even in the branches. In this nest they sleep and raise their young. The life span can be 13 years for some species, but is usually shorter. Through its lubricity succeeds flying squirrels often to escape tree-dwelling predators such as martens, but they are against birds of prey and owls at a disadvantage. In Southeast Asia, the Maskeneule has really specialized in the hunting of flying squirrels.

Dissemination

Although flying squirrels live in North America, Europe and northern Asia, the focus of their range is clearly on East and Southeast Asia. Especially in the Indonesian archipelago, there is a remarkable diversity of species; many of these species are poorly understood.

System

External system

Belonging to the family of the Flying Squirrel Squirrel is undisputed. In older classifications were performed as a family in which they were compared with all the other squirrels, which as a collective group of " earth and tree squirrels " ( Sciurinae ) are combined. While even some Kladistiker it thought possible long that both taxa are monophyletic sister groups, this was doubted by others.

Steppan, Storz and Hoffmann came in 2003 in their DNA analysis to conclude that the earth and tree squirrels are a paraphyletic taxon and the flying squirrel would have resulted from this. Flying squirrels and tree squirrels (including red squirrels ) form on their studies, a common clade; herein are the flying squirrel, the sister group of the tree squirrels. The monophyly of the flying squirrel has been demonstrated in the study.

Internal system

The following genera are distinguished:

• Riesengleithörnchen ( Petaurista )
• Namdapha flying squirrel ( Biswamoyopterus )
• Black Flying Squirrel ( Aeromys )
• Felsgleithörnchen ( Eupetaurus )
• Real flying squirrels ( Pteromys )
• New World flying squirrels ( Glaucomys )
• Kashmir Flying Squirrel ( Eoglaucomys )
• Horseshoe flying squirrel ( Hylopetes )
• Zwerggleithörnchen ( Petinomys )
• Furrows tooth flying squirrel ( Aeretes )
• Complex tooth flying squirrel ( Trogopterus )
• Haarfuß flying squirrel ( Belomys )
• Smoke Grey Flying Squirrel ( Pteromyscus )
• Kleinstgleithörnchen ( Petaurillus )
• Horsfield flying squirrel ( Iomys )

The relationships of the genera among themselves were largely unknown until Thorington, Pitassy and Jansa 2002 published their extensive phylogenetic analyzes. According to this study, the Flying Squirrel in four clades can be grouped, named as Trogopterus group Petaurista group Hylopetes - Petinomys group and Glaucomys group. The following cladogram shows the relationships between the " groups " and classes is:

Pteromyscus

Belomys

Trogopterus

Aeromys

Eupetaurus

Pteromys

Aeretes

Petaurista

Petinomys

Hylopetes

Petaurillus

Eoglaucomys

Glaucomys

Iomys

The genus Biswamoyopterus was not involved in the study, so that their position is unclear in this system.

Fossil history

The oldest fossil Flying Squirrel genus Oligopetes lived in the early Oligocene in Europe. However, this finding was associated only because of dental features the flying squirrel, so that some paleontologists doubt whether it has actually traded a real flying squirrel.

Without a doubt, are occupied flying squirrel since the Miocene of Eurasia and North America. Extinct genera of flying squirrels are:

• Petauristodon, Miocene, North America
• Miopetaurista, Miocene to Pliocene, North America and Eurasia
• Aliveria, Miocene, Europe
• Shuanggouia, Miocene, Asia
• Blackia, Miocene to Pliocene, Europe and North America
• Forsythia, Miocene, Europe
• Albanensis, Miocene, Eurasia
• Meinia, Miocene, Asia
• Pliopetaurista, Miocene to Pleistocene, Eurasia
• Pliosciuropterus, Miocene to Pliocene, Europe
• Parapetaurista, Miocene, Asia
• Petauria, Pleistocene, Europe

In addition, some of the recent genera are fossil evidence. The oldest of the extant genera seem to be Hylopetes that is proven since the Miocene in Asia. The genus of the Real flying squirrel fossil is known since the Pliocene.

Nomenclature

The valid scientific name of flying squirrel is Pteromyini. Occasionally one also applies to the designation Petauristinae. This was coined in the 1940s, as was thought Pteromys for a synonym of Petaurista and so logically renamed the whole group. Meanwhile, there is no longer any doubt as to the validity of the name Pteromys, so coined by Johann Friedrich von Brandt Pteromyini name should be used.