Patagium

As patagium ( patagium ), also flight or Gleitmembran is called serving as a wing skin (with or without supporting structures ) in vertebrates.

Wing membranes have been developed in all five classes of vertebrates, but emerged only in two classes real membrane airmen who were capable of active flapping flight: in mammals, the bats ( Chiroptera ) and, in geological past, in reptiles, the pterosaurs ( Pterosauria ). In the other recent and fossil species, the membrane is used for passive slide or parachute flight, as the extended jump from tree to tree or from the tree to the ground, which is often supported by fluttering movement. These species can not actively determine the direction, height and duration of the flight.

The structures from which wing membranes were formed, and their location on the body are different depending on the type.

Mammals

In mammals, there are three body areas where a flight membrane can be formed:

• The flight neck skin ( Propatagium ) extends between neck and forelimb.
• The arm or flank wing membrane ( Plagiopatagium ) pulls along the side of the body between the front and hind.
• The tail wing membrane ( Uropatagium ) extends from the tail to the hind limb.

These sections of the wing membrane are present in mammals as follows:

• Giant slide ( Dermoptera ): Pro-, Plagio and Uropatagium
• Flying Squirrel ( Pteromyinae ): Plagiopatagium; Pro- and Uropatagium very small
• Thorn tail squirrel ( Anomaluridae ): Plagio and Uropatagium
• Gleitbeutler ( Petauridae ): haired Plagiopatagium

Especially with the Fledertieren ( Chiroptera ) comes to pro, Plagio and Uropatagium a fourth body area added: Between her highly elongated metacarpal and finger bones, a large part of the total flight skin is stretched. This is called the Dactylopatagium ( " finger flight skin") or Chiropatagium ( " hand wing membrane "). When the giant gliders flying membrane is between the fingers and toes, although also present, among them makes the Chiropatagium but only a small proportion of the total flight skin.

The fruit bats ( Megachiroptera ) the Uropatagium is only a narrow strip of skin on the hind legs, because they have no or only a very short tail.

In birds, wing membranes brace the different parts of the bird's wing together, fill in the spaces between the bones and limit the wing core forwards and backwards. Most important are the front wing membrane, the rear wing membrane and the large Randligamend between elbows and metacarpal bones.

By feathers the wing area is further enlarged. The flight feathers are the largest feathers on the wing and are divided according to insertion site in primaries and secondaries. A connective tissue band keeps it in the correct position. They grab each other like roof tiles.

Reptiles

Flying Dragons ( Draco; Agamidae ) are gliders and have lateral skin flaps, which are spanned with extended fins, while the rest are the wing membranes folded. Due to the flattened body also the aerodynamic properties are improved, while the tail serves as a rudder. In this way they can slide up to eight meters.

Bonefish

Flying fish ( Exocoetidae ) fast to. Due to short, quick strokes with the extended at the bottom of the tail fin out of the water and sailing with the large, wing-like expandable pectoral fins usually one meter, with favorable updrafts also to almost 10 meters high above the water surface Already more than 200 million years ago lived in the Palaeotethys, in the area of ​​today's Mediterranean Sea and the Alps, the Thoracopteridae a family slippery fish bones and the oldest known slippery fish. In the fossil record, the much wider pectoral fins and the extended base of the caudal fin are clearly visible.

Amphibians

Between the fingers and toes of the authentics rowing frogs ( Rhacophorus ) from Southeast Asia, a Gleitmembran clamped on. This will spread out after take-off and allows sliding from tree to tree. Thus, the animals can change their habitat energy saving and avoiding the dangerous ground region or escape predators.