nietoperze: Okapi

Evidence: 91 • authority: 72

The okapi (; Okapia johnstoni), also known as forest giraffe and zebra giraffe, is an artiodactyl mammal that is endemic to the northeast Democratic Republic of the Congo. It is the only species in the genus Okapia. Although the okapi has striped markings reminiscent of zebras, it is most closely related to the giraffe. The okapi and the giraffe are the only living members of the family Giraffidae. The okapi stands about 1.5 m (4 ft 11 in) tall at the shoulder and has a typical body length around 2.5 m (8 ft 2 in). Its weight ranges from 200 to 350 kg (440 to 770 lb). It has a long neck, and large, flexible ears. Its coat is a chocolate to reddish brown, much in contrast with the white hori…

Evidence: 32 • authority: 72

Ossicones are columnar or conical skin-covered bone structures on the heads of giraffes, male okapi, and some of their extinct relatives. Ossicones are distinguished from the superficially similar structures of horns and antlers by their unique development and a permanent covering of skin and fur.

Evidence: 32 • authority: 92

Heads up-Four Giraffa species have distinct cranial morphology.. Giraffe (Giraffa spp.) are among the most unique extant mammals in terms of anatomy, phylogeny, and ecology. However, aspects of their evolution, ontogeny, and taxonomy are unresolved, retaining lingering questions that are pivotal for their conservation. We assembled the largest known dataset of Giraffa skulls (n = 515) to investigate patterns of cranial variability using 3D geometric morphometrics. The results show distinct sexual dimorphism and divergent ontogenetic trajectories of skull shape for the north clade (G. camelopardalis antiquorum, G. c. camelopardalis, G. c. peralta, and G. reticulata) and the south clade (G. g…

Evidence: 24 • authority: 92

The variability of giraffe skull morphology.. Giraffe (Giraffa spp.) are among the most unique and charismatic extant animals, largely due to their distinct morphology. The evolutionary and developmental origin of ossicones is a key factor in giraffid biology, yet other features building their characteristic head physiognomy remain poorly studied. Here, we analysed the cranial diversity of extant Giraffa using a continent-wide sample with a balanced sex ratio and ontogenetic growth series, using shape analysis (3D geometric morphometrics). Detailed comparisons showed significant differences in cranial morphology across the four Giraffa species, and in some cases also between subspecies of t…

Evidence: 24 • authority: 92

Cranial Appendages in Ruminants: Diversity, Evolution, Development, and Molecular Basis of Horns, Pronghorns, Antlers, and Ossicones.. Ruminants are unique among living mammals in possessing paired bony cranial appendages in the form of horns, pronghorns, antlers, or ossicones. This review summarizes current knowledge on the structure, development, function, and evolution of these appendages and integrates recent findings from genomics, transcriptomics, and single-cell analyses. Two competing hypotheses have been proposed to explain their origin. According to the independent-origin hypothesis, horns, pronghorns, antlers, and ossicones evolved separately in different pecoran lineages, possib…

Evidence: 24 • authority: 72

Giraffes (genus Giraffa) are large African hoofed mammals. They are the tallest living terrestrial animals and the largest ruminants on Earth. They are classified under the family Giraffidae, along with their closest extant relative, the okapi. Traditionally, giraffes have been thought of as one species, Giraffa camelopardalis, with nine subspecies. Most recently, researchers proposed dividing them into four extant species, with seven subspecies, which can be distinguished morphologically by their fur coat patterns. Six valid extinct species of Giraffa are known from the fossil record. The distinguishing characteristics of giraffes are their extremely long neck and legs, horn-like ossicones…