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Orycteropodidae is a family of Afrotherian mammals. Although there are many fossil species, the only species surviving today is the aardvark, ''Orycteropus afer''. Orycteropodidae is recognized as the only family within the order Tubulidentata, so the two are effectively synonyms. Only recently did scientists discover that the aardvark and the anteater evolved from two different families and separated the two species. They were classified in the order Edentata due to their similar physical characteristics and diets. The phylogeny of this family has never been fully analyzed, making it hard to trace back the evolutionary history, and the amount of unknown information limits the knowledge of the species. Orycteropodidae members are polygynous, the females providing care for the young. They are territorial, and only cross paths to breed. The males' genitals create a musk while females create this musk from glands in their elbows, this scent helps mating occur. The gestation period lasts about 7 months, and they are dependent upon the mother until they are 6 months of age, becoming sexually mature at 2 years of age. Breeding occurs once a year, they produce one offspring, and will have maybe one to two more in their lifetime. Representatives of the order ''Tubulidentata'' have been located from the Oligocene in what is now Europe, and it is believed that the order probably originated around 65–70 million years ago or in the Paleocene. They are thought to be closely related to the now extinct Ptolemaiida, a lineage of carnivorous afrotheres. The family arose in Africa in the Early Miocene Epoch, and spread to Eurasia later in the Miocene. Most of the family's diversity had become extinct by the end of the Pliocene.〔 Aardvarks are myrmecoagous, eating almost strictly on termites and ants. They rely on their sense of smell to find most of their food and hunt at night. == Characters == A few anatomical characters unite the Orycteropodidae and Tubulidentata. * the occipital region has extensive mastoid exposure * the teeth have a distinctive structure called tubulidentate microstructure. These animals lack incisors and canines, and have between 20-22 teeth. These teeth also lack enamel, and are just rounded structures of dentine. The teeth are evergrowing, so unrooted, and are diphydont. Antoher unique trait is that their small milk teeth are lost before the animal is born. * the femur has a pectineal tubercle * the diaphysis of the tibia is curved mediolaterally 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Orycteropodidae」の詳細全文を読む スポンサード リンク
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