Ailuropodinae

Ailuropodinae is a subfamily of Ursidae that contains only one extant species, the giant panda (Ailuropoda melanoleuca) of China. The fossil record of this group has shown that various species of pandas were more widespread across the Holarctic, with species found in places such as Europe, much of Asia, North America and even Africa. The earliest pandas were not unlike other modern bear species in that they had an omnivorous diet but by around 2.4 million years ago, pandas had evolved to be more herbivorous. The giant panda (Ailuropoda) belongs to the order of Carnivora, this means that the macronutrients that are digested are more similar to those of carnivores than to that of herbivores even though their diet consists mainly of bamboo.

Systematics

Ever since the giant panda was first described to science, they have been a source of taxonomic confusion, having been variously classified as a member of Procyonidae, Ursidae, Ailuridae, or even their own family Ailuropodidae. Part of their similarities with the red panda is in particular the presence of a "thumb" and five fingers; the "thumb" – a modified sesamoid bone – that helps it to hold bamboo while eating.

Recent genetic studies have shown that ailuropodines are indeed members of the bear family as they are not closely related to red pandas, which are placed in their own family Ailuridae. Any similarities between ailuropodines and ailurids are likely due to convergent evolution as the fossil record has shown the "false thumb" has been required independently for different purposes. The "false thumb" has been found in spectacled bears as well, suggesting that it is a plesiomorphic trait among bears that became lost in the Ursinae subfamily.

Taxonomy

The ailuropodines are divided into two tribes the extinct Agriotheriini and Ailuropodini; the following taxonomy below is after Abella et al. (2012):

• Subfamily Ailuropodinae <small>Grevé, 1894</small>
• Tribe †Agriotheriini <small>Kretzoi, 1929</small>
• †Agriotherium <small>Wagner, 1837</small>
• †Agriotherium africanum <small>Hendey, 1972</small>
• †Agriotherium gregoryi <small>Frick, 1926</small>
• †Agriotherium hendeyi <small>Jiangzuo & Flynn, 2019</small>
• †Agriotherium inexpetans <small>Qiu et al., 1991</small>
• †Agriotherium insigne <small>Gervais, 1859</small>
• †Agriotherium myanmarensis <small>Ogino et al., 2011</small>
• †Agriotherium palaeindicus <small>Lydekker, 1878</small>
• †Agriotherium sivalensis <small>(Falconer & Cautley, 1836)</small>
• †Huracan <small>Jiangzuo et al., 2023</small>
• †Huracan coffeyi <small>(Dalquest, 1986)</small>
• †Huracan qiui <small>Jiangzhou et al., 2023</small>
• †Huracan schneideri <small>(Sellards, 1916)</small>
• †Huracan? punjabensis <small>(Lydekker, 1884)</small> [Indarctos punjabensis <small>(Lydekker, 1884)</small>]
• †Huracan? roblesi <small>(Morales & Aguirre, 1976)</small> [Agriotherium roblesi <small>Morales & Aguirre, 1976</small>]
• †Indarctos <small>Pilgrim, 1913</small>
• †Indarctos anthracitis <small>(Weithofer, 1888)</small>
• †Indarctos arctoides <small>(Deperet, 1895)</small>
• †Indarctos atticus <small>(Weithofer, 1888)</small>
• †Indarctos bakalovi <small>(Kovachev, 1988)</small>
• †Indarctos lagrelli <small>(Zdansky, 1924)</small>
• †Indarctos nevadensis <small>Macdonald, 1959</small>
• †Indarctos oregonensis <small>Merriam et al., 1916</small>
• †Indarctos salmontanus <small>Pilgrim, 1913</small>
• †Indarctos sinensis <small>(Zdansky, 1924)</small>
• †Indarctos vireti <small>Villalta & Crusafont, 1943</small>
• †Indarctos zdanskyi <small>Qiu & Tedford, 2003</small>
• ?†Miomaci <small>de Bonis et al., 2017</small>
• †Miomaci pannonicum <small>de Bonis et al., 2017</small>
• Tribe Ailuropodini <small>Grevé, 1894</small>
• Ailuropoda <small>Milne-Edwards, 1870</small>
• Ailuropoda melanoleuca <small>David, 1869</small> – giant panda
• †Ailuropoda baconi <small>Woodward 1915</small>
• †Ailuropoda microta <small>Pei, 1962</small>
• †Ailuropoda wulingshanensis <small>Wang & Alii, 1982</small>
• †Agriarctos <small>Kretzoi, 1942</small>
• †Agriarctos depereti <small>(Schlosser, 1902)</small>
• †Agriarctos gaali <small>Kretzoi, 1942</small>
• †Agriarctos nikolovi <small>Jiangzuo & Spassov, 2022</small>
• †Agriarctos vighi <small>Kretzoi, 1942</small>
• †Ailurarctos <small>Qi et al., 1989</small>
• †Ailurarctos lufengensis <small>Qi et al., 1989</small>
• †Ailurarctos yuanmouensis <small>Zong, 1997</small>
• †Kretzoiarctos <small>Abella et al., 2012</small>
• †Kretzoiarctos beatrix <small>Abella et al., 2011</small>

References