Forehead weapon carrier

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Forehead weapon carrier
Gauntlet (oryx gazella)

Gauntlet ( oryx gazella )

Systematics
Class : Mammals (mammalia)
Subclass : Higher mammals (Eutheria)
Superordinate : Laurasiatheria
Order : Artiodactyla (Artiodactyla)
Subordination : Ruminants (ruminantia)
without rank: Forehead weapon carrier
Scientific name
Pecora
Flower , 1883
Familys

The forehead weapon bearers (Pecora) are a taxon (a systematic group of creatures) within the artifacts .

features

The forehead armament

The eponymous feature are the forehead weapons. These are mostly outgrowths of the frontal bone , which are built differently depending on the family. However , they are absent in two genera, the musk deer and the water twist .

  • The deer (Cervidae) are characterized by antlers that grow from cone-shaped bones ("rose bushes"). It consists of bone substance and is shed and newly formed every year after the mating season.
  • The hornbeams (Bovidae), on the other hand, have horns made of horny substance , which are usually retained for a lifetime. The skin that covers the bone cone sheds horny cells, which eventually thicken into a hard horny sheath. The oldest horn layers move further and further towards the horn tip and at least the outer part of the horn is hollow. With the exception of the four-horned antelope , all horn carriers have two horns.
  • In the case of the fork-horned bearers (Antilocapridae), the horns are formed similarly to those of the horned bearers, but in contrast, the horn sheaths are shed annually.

The forehead weapons can be used for showing off, fighting for mating privilege and also for defense. In almost all cases they are sexually dimorphic , that is, larger in males than in females. In some species, such as almost all deer, some forest goats and the okapi , the females lack forehead armament.

Other specifications

The height of the forehead weapon carriers varies considerably. Some representatives such as the bucks or pudus are very small, in contrast to cattle or giraffes can weigh more than a ton. As artifacts , the forehead weapon bearers share the characteristics of this group, the relatively immobile feet with two or four toes, which are used for rapid locomotion. They are ruminants , so they have a four-chambered stomach, which is used to better utilize the plant food.

Distribution and way of life

Forehead weapon carriers are widespread almost worldwide, they occur in America , Eurasia and Africa . They are pure herbivores and often live in hierarchically structured groups. Some representatives (such as domestic cattle , domestic sheep and domestic goats ) have achieved worldwide importance as domestic animals, others have been distributed worldwide as park and hunting animals, but still others have been pushed to the brink of extinction by hunting and habitat destruction .

Systematics

The forehead weapon bearers are the sister group of the deer piglets , which differ from them by a three-chambered stomach and the lack of forehead weapons. Together they form the subordination of the ruminants (Ruminantia) in the order of the ungulate or the Cetartiodactyla .

 
 Forehead weapon bearer (Pecora) 

 Giraffes (Giraffidae)


   

 Musk deer (moschidae)


   

 Forked horns (Antilocapridae)


   

 Deer (Cervidae)


   

 Horned Bearers (Bovidae)


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The following five recent families are included:

The internal system of the forehead weapon carriers is confusing and controversial. Although deer, musk deer and fork-horned bearers have traditionally been grouped together as deer-like (Cervoidea), different molecular studies provide different - and inconsistent - results, so that the question of a phylogenetic system of forehead weapon bearers cannot yet be clearly answered.

literature

  • Wilfried Westheide , Reinhard Rieger (Hrsg.): Special zoology. Part 2: vertebrates or skulls. Spectrum Akademischer Verlag, Heidelberg - Berlin 2004, 712 pages, ISBN 3-8274-0307-3 .