Orycteropodidae
| Orycteropodidae Temporal range: 20–0 Ma | |
|---|---|
 | |
| Orycteropus afer - Aardvark | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Superorder: | Afrotheria |
| (unranked): | Afroinsectiphilia |
| Order: | Tubulidentata |
| Family: | Orycteropodidae |
| Genera | |
|
Orycteropus | |
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.[1][2]
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.[3][4] They are thought to be closely related to the now extinct Ptolemaiida, a lineage of carnivorous afrotheres.[5] [6] 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.[1]
Aardvarks are myrmecophagous, 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. Another 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 [[Anatomical terms of location#Left and right
.28lateral.29.2C and medial|mediolaterally]]
Classification
This classification follows Lehmann 2009.[1]
- Genus Amphiorycteropus Lehmann 2009
- † Amphiorycteropus gaudryi (Major, 1888) - type species
- † Amphiorycteropus abundulafus (Lehmann et al., 2005) [7]
- † Amphiorycteropus browni (Colbert, 1933) (= Orycteropus pilgrimi Colbert, 1933)
- † Amphiorycteropus depereti (Helbing, 1933)
- † Amphiorycteropus mauritanicus (Arambourg, 1959)
- † affinis (resembling) Amphiorycteropus
- † aff. Amphiorycteropus pottieri (Ozansoy, 1965)
- † aff. Amphiorycteropus seni (Tekkaya, 1993)
- Genus Orycteropus Geoffroy St. Hilaire, 1796
- Orycteropus afer - Aardvark (type species)
- † Orycteropus crassidens MacInnes, 1956
- † Orycteropus djourabensis Lehmann et al., 2004
- † Orycteropus abundulafus Lehmann, 2005
- Genus †Leptorycteropus Patterson, 1975
- †Leptorycteropus guilielmi Patterson, 1975 - type species
- Genus † Myorycteropus MacInnes, 1956
- † Myorycteropus africanus MacInnes, 1956 - type species
- † affinis (resembling) Myorycteropus
- † aff. Myorycteropus chemeldoi (Pickford, 1975)
- † aff. Myorycteropus minutus (Pickford, 1975)
Footnotes
- 1 2 3 4 5 Lehmann 2009
- ↑ Schlitter 2005, p. 86
- ↑ Shoshani 2002, p. 619
- ↑ Shoshani 2002, p. 620
- ↑ Cote S, Werdelin L, Seiffert ER, Barry JC (March 2007). "Additional material of the enigmatic Early Miocene mammal Kelba and its relationship to the order Ptolemaiida". Proc Natl Acad Sci USA. 104 (13): 5510–5. Bibcode:2007PNAS..104.5510C. doi:10.1073/pnas.0700441104. PMC 1838468. PMID 17372202.
- ↑ Seiffert, Erik R (2007). "A new estimate of afrotherian phylogeny based on simultaneous analysis of genomic, morphological, and fossil evidence". BMC Evolutionary Biology 7 (1): 224. doi:10.1186/1471-2148-7-224. PMC 2248600. PMID 17999766.
- ↑ Lehmann et al. 2005
References
- Lehmann, Thomas (2009). "Phylogeny and systematics of the Orycteropodidae (Mammalia, Tubulidentata)". Zoological Journal of the Linnean Society 155: 649–702. doi:10.1111/j.1096-3642.2008.00460.x.
- Lehmann, Thomas; Vignaud, Patrick; Likius, Andossa; Brunet, Michel (2005). "A new species of Orycteropodidae (Mammalia, Tubulidentata) in the Mio-Pliocene of northern Chad". Zoological Journal of the Linnean Society 143 (1): 109–131. doi:10.1111/j.1096-3642.2004.00143.x.
- Schlitter, D.A. (2005). "Order Tubulidentata". In Wilson, D.E.; Reeder, D.M. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. p. 86. ISBN 978-0-8018-8221-0. OCLC 62265494.
- Shoshani, Jeheskel (2002). "Tubulidentata". In Robertson, Sarah. Encyclopedia of Life Sciences. 18: Svedberg, Theodor to Two-hybrid and Related Systems. London, UK: Nature Publishing Group. ISBN 1-56159-274-9.
Further reading
- "A sub-complete fossil aardvark (Mammalia, Tubulidentata) from the Upper Miocene of Chad". doi:10.1016/j.crpv.2005.12.016
- MacInnes D. G. (1956). Fossil Tubulidentata from East Africa. British Museum (Natural History), London. Fossil mammals of Africa series; no. 10. 46 pp.