Ailuropodinae Explained

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.^{[1] [2] [3] [4]} 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 have evolved to be more herbivorous.^{[5] [6]}

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,^{[7] [8] [9]} Ursidae,^{[10] [11] [12]} Ailuridae,^[13] or even their own family Ailuropodidae.^[14] 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.^[15]

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.^{[16] [17]} 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.^[18] 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.^[19]

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 Grevé, 1894^[20]
  • Tribe †Agriotheriini Kretzoi, 1929^[21]
    • ?†Miomaci de Bonis et al., 2017
      • †Miomaci pannonicum de Bonis et al., 2017
    • †Indarctos Pilgrim, 1913
      • †Indarctos zdanskyi Qiu & Tedford, 2003^[22]
      • †Indarctos sinensis (Zdansky, 1924)
      • †Indarctos vireti Villalta & Crusafont, 1943
      • †Indarctos arctoides (Deperet, 1895)
      • †Indarctos anthracitis (Weithofer, 1888)
      • †Indarctos salmontanus Pilgrim, 1913
      • †Indarctos atticus (Weithofer, 1888)
      • †Indarctos bakalovi (Kovachev, 1988)
      • †Indarctos lagrelli (Zdansky, 1924
      • †Indarctos oregonensis Merriam et al., 1916
      • †Indarctos nevadensis Macdonald, 1959^[23]
    • †Huracan Jiangzuo et al., 2023
      • †Huracan? roblesi (Morales & Aguirre, 1976) [''Agriotherium roblesi'' <small>Morales & Aguirre, 1976</small>]
      • †Huracan? punjabensis (Lydekker, 1884) [''Indarctos punjabensis'' <small>(Lydekker, 1884)</small>]
      • †Huracan schneideri (Sellards, 1916)
      • †Huracan coffeyi (Dalquest, 1986)
      • †Huracan qiui Jiangzhou et al., 2023
    • †Agriotherium Wagner, 1837
      • †Agriotherium hendeyi Jiangzuo & Flynn, 2019
      • †Agriotherium myanmarensis Ogino et al., 2011
      • †Agriotherium insigne Gervais, 1859
      • †Agriotherium inexpetans Qiu et al., 1991
      • †Agriotherium palaeindicus Lydekker, 1878
      • †Agriotherium sivalensis (Falconer & Cautley, 1836)
      • †Agriotherium africanum Hendey, 1972
      • †Agriotherium gregoryi Frick, 1926
  • Tribe Ailuropodini Grevé, 1894
    • †Kretzoiarctos Abella et al., 2012
      • †Kretzoiarctos beatrix Abella et al., 2011
    • †Agriarctos Kretzoi, 1942^[24]
      • †Agriarctos depereti (Schlosser, 1902)
      • †Agriarctos gaali Kretzoi, 1942
      • †Agriarctos nikolovi Jiangzuo & Spassov, 2022
      • †Agriarctos vighi Kretzoi, 1942
    • †Ailurarctos Qi et al., 1989
      • †Ailurarctos yuanmouensis Zong, 1997
      • †Ailurarctos lufengensis Qi et al., 1989
    • Ailuropoda Milne-Edwards, 1870
      • †Ailuropoda microta Pei, 1962
      • †Ailuropoda wulingshanensis Wang & Alii, 1982
      • †Ailuropoda baconi Woodward 1915
      • Ailuropoda melanoleuca David, 1869 – giant panda

Notes and References

1. Ginsburg, Léonard, and Jorge Morales. "Hemicyoninae (Ursidae, Carnivora, Mammalia) and the related taxa from Early and Middle Miocene of Western Europe." Annales de paleontologie. Vol. 1. No. 84. 1998.
2. Montoya, P., L. Alcalá, and Jorge Morales. Indarctos (Ursidae, Mammalia) from the Spanish Turolian (Upper Miocene). Nationaal Natuurhistorisch Museum, 2001.
3. Abella, J., Plinio Montoya, and J. Morales. "Una nueva especie de Agriarctos (Ailuropodinae, Ursidae, Carnivora) en la localidad de Nombrevilla 2 (Zaragoza, España)." Estudios Geológicos 67.2 (2011): 187-191.
4. Abella. Juan. Alba. David M.. Robles. Josep M.. Valenciano. Alberto. Rotgers. Cheyenn. Carmona. Raül. Montoya. Plinio. Morales. Jorge. O’Grady. Patrick. Kretzoiarctos gen. nov., the Oldest Member of the Giant Panda Clade. PLOS ONE. 2012. 7. 11. e48985. 10.1371/journal.pone.0048985. 23155439. 3498366. free. 2012PLoSO...748985A.
5. Jin. C. Ciochon. R. L.. Dong. W. Hunt Jr. R. M.. Liu. J. Jaeger. M. Zhu. Q. The first skull of the earliest giant panda. Proceedings of the National Academy of Sciences of the United States of America. 2007. 104. 26. 10932–10937. 10.1073/pnas.0704198104. 17578912. 1904166. 2007PNAS..10410932J. free.
6. Zhao. S. Zheng. P. Dong. S. Zhan. X. Wu. Q. Guo. X. Hu. Y. He. W. Zhang. S. Fan. W. Zhu. L. Li. D. Zhang. X. Chen. Q. Zhang. H. Zhang. Z. Jin. X. Zhang. J. Yang. H. Wang. J. Wang. J. Wei. F. Whole-genome sequencing of giant pandas provides insights into demographic history and local adaptation. Nature Genetics. 2013. 45. 1. 67–71. 10.1038/ng.2494. 23242367. 1261505.
7. Lankester . E. Ray . Milne-Edwards . A. . September 1901 . On the Affinities of Æluropus melanoleucus . Transactions of the Linnean Society of London. 2nd Series: Zoology . en . 8 . 6 . 163–172 . 10.1111/j.1096-3642.1901.tb00505.x.
8. Gregory . William K. . 1936-08-08 . On the phylogenetic relationships of the giant panda (Ailuropoda) to other arctoid Carnivora . American Museum Latin: Novitates . New York City . . 838 . 1–29. 2246/4138 .
9. Welker . W. I. . Campos . G. B. . February 1963 . Physiological significance of sulci in somatic sensory cerebral cortex in mammals of the family procyonidae . The Journal of Comparative Neurology . en . 120 . 1 . 19–36 . 10.1002/cne.901200103 . 13999831 . 33127965 . 0021-9967 . subscription.
10. O'Brien . Stephen J. . Nash . William G. . Wildt . David E. . Bush . Mitchell E. . Benveniste . Raoul E. . September 1985 . A molecular solution to the riddle of the giant panda's phylogeny . . en . 317 . 6033 . 140–144 . 10.1038/317140a0 . 4033795 . 1985Natur.317..140O . 4352629 . 0028-0836 . subscription.
11. O'Brien . S. J. . Eichelberger . M. A. . Wildt . D. E. . Bush . M. . 2 . 1984 . Constructing a molecular phylogeny of the giant panda (Ailuropoda melanoleuca) . Bongo . Berlin . Proceedings of the International Symposium on Giant Panda . 10 . 175–182.
12. Pastor . J. F. . Barbosa . M. . de Paz . F. J. . February 2008 . Morphological study of the lingual papillae of the giant panda (Ailuropoda melanoleuca) by scanning electron microscopy . Journal of Anatomy . en . 212 . 2 . 99–105 . 10.1111/j.1469-7580.2008.00850.x . 0021-8782 . 2408975 . 18254792.
13. Thenius . Von E. . 1989-02-18 . Molekulare und., "adaptive" Evolution, Kladistik und Stammesgeschichte: Ergänzungen zu einer Arbeitshypothese . Molecular and adaptive evolution, cladistics, and phylogeny: additions toward a working hypothesis . Zeitschrift für Zoologische Systematik und Evolutionsforschung. 27 . 2 . 94–105 . 10.1111/j.1439-0469.1989.tb00334.x . free .
14. Thenius . Von E. . 1979 . Zur Systematischen und phylogenetischen Stellung des Bambusbären: Ailuropoda melanoleuca David (Carnivora, Mammalia) . On the systematic and phylogenetic position of the bamboo bear: Ailuropoda melanoleuca David (Carnivora, Mammalia) . Zeitschrift für Säugetierkunde . 44 . 1 . 283–305 . 0044-3468 . https://web.archive.org/web/20230529184204/https://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&idt=PASCAL8050177643 . 29 May 2023 . 29 May 2023 . bot: unknown .
15. Web site: The Panda's Thumb. Morris. Paul. Susan F. Morris. Athro Limited. 7 August 2010.
16. Peng, Rui, et al. "The complete mitochondrial genome and phylogenetic analysis of the giant panda (Ailuropoda melanoleuca)." Gene 397.1 (2007): 76-83.
17. Sato, Jun J., et al. "Deciphering and dating the red panda’s ancestry and early adaptive radiation of Musteloidea." Molecular Phylogenetics and Evolution 53.3 (2009): 907-922.
18. Salesa, Manuel J., et al. "Evidence of a false thumb in a fossil carnivore clarifies the evolution of pandas." Proceedings of the National Academy of Sciences of the United States of America 103.2 (2006): 379-382.
19. Salesa, Manuel J., et al. "Anatomy of the “false thumb” of Tremarctos ornatus (Carnivora, Ursidae, Tremarctinae): phylogenetic and functional implications." (2006).
20. Abella, Juan. etal. Kretzoiarctos gen. nov., the oldest member of the giant panda clade . PLOS ONE . 7 . 11 . 2012 . e48985 . 10.1371/journal.pone.0048985 . 23155439 . 3498366. 2012PLoSO...748985A. free.
21. Jiangzuo . Q. . Flynn . J. J. . Wang . S. . Hou . S. . Deng . T. . New fossil giant panda relatives (Ailuropodinae, Ursidae): a basal lineage of gigantic Mio-Pliocene cursorial carnivores . American Museum Novitates . 2023 . 3996 . 1–71 . 10.1206/3996.1 . 2246/7315 . 257508340 . free .
22. Qiu. Zhan-Xiang. Tedford. R. H.. Vertebrata PalAsiatica. 2003. 41. 4. 278–288. Shānxī bǎo dé yìndù xióngyīxīn zhǒng. A New Species of *Indarctos* from Baode, China. zh:山西保德印度熊一新种.
23. MacDonald. J. R.. The Middle Pliocene Mammalian Fauna from Smiths Valley, Nevada. Journal of Paleontology. 1959. 33. 5. 872–887. 1300922.
24. Kretzoi. M.. Zwei neue Agriotheriiden aus dem ungarischen Pannon. Földtani Közlöny. 1942. 72. 350–353.