目前学界普遍认同家猫是从非洲野猫中驯化而来的。大约在9000年前的新石器时代,新月沃地的非洲野猫与早期农业社会的人类发展出伴生关系(Driscoll et al., 2007; Ottoni et al., 2017)。大概6000年前起,它们开始随人类活动向欧洲扩散。而生活在埃及的非洲野猫,在大约4000年前参与到了家猫的驯化过程中。埃及人的驯化被认为是家猫社会性和驯服行为上发生改变的关键因素(Ottoni et al., 2017)。之后,随人类的战争、贸易和航海等活动,家猫扩散到除南极洲外的各大洲。
家猫通常被排除在野猫之外,即使是野生状态下的家猫(它们应该被称为野化家猫)也不属于野猫。按照谱系发生学的观点,家猫应当归属于非洲野猫。然而,经历了漫长的驯化过程,家猫在遗传、形态和行为等多方面已和世世代代生活在野外的祖先们产生了显著的差异。为了便于区别对待野猫和家猫,家猫通常被作为一个单独的物种或者亚种(Yamaguchi et al., 2015)。
2007年Driscoll等的文章,报道了在欧洲野猫、南非野猫和亚洲野猫中出现非洲野猫/家猫的线粒体单倍型,而这3个地区的家猫种群中也存在当地野猫的线粒体单倍型。微卫星分型的分析进一步确认了上述3个亚种与家猫之间的基因交流。西亚地区的非洲野猫和当地家猫则混合形成一个大的种群,无论是线粒体还是微卫星都难以检测到种群结构的差异(Driscoll et al., 2007)。此外,Sanderson等推测家猫和荒漠猫之间也存在基因交流(Sanderson et al., 2010; 尹玉峰, 2008)。
因此,“合猫派”基于生物学物种概念(Biological Species Concept,BSC),认为所有野猫应当作为同一物种下的5个不同亚种。
树状结构为微卫星位点的聚类结果,圆圈、正方形、三角形和五角星表示线粒体基因与微卫星聚类不相符的个体,橙色对应非洲野猫和家猫,绿色对应欧洲野猫,蓝色对应南非野猫,紫色对应亚洲野猫,红色对应荒漠猫。引自Fig. 1.(Driscoll et al., 2007)
接着,这篇文章引用了2005年Yamaguchi等的头骨形态学研究的结论,相比于欧洲野猫,亚洲野猫和南非野猫的差异更小(Yamaguchi et al., 2004)。最后,Kitchener等还引用2007年Driscoll分子遗传学研究的结果,非洲野猫、南非野猫和亚洲野猫遗传关系最近,而欧洲野猫的分歧时间更早(Driscoll et al., 2007)。
依据以上三点,他们认为欧洲野猫是一个符合谱系发育学物种概念(Phylogenetic Species Concept,PSC)的独立物种,而亚洲野猫、非洲野猫和南非野猫是同一个物种下的3个亚种(Kitchener & Rees, 2009)。
此外,“分猫派”依据“荒漠猫可能与亚洲野猫同域分布,而在形态上仍保持着明显的差异”,推测荒漠猫与亚洲野猫之间存在生殖隔离,认为荒漠猫是符合生物学物种概念(BSC)和谱系发生学物种概念(PSC)的独立物种 (Kitchener et al., 2017; Kitchener & Rees, 2009)。
有趣的是,在2017年的最新分类名录中欧洲野猫的章节有这么一段“异见”,将野猫的分类学争议悠悠道来:“However, C. Driscoll (pers. comm.) retains lybica, cafra, ornata and bieti within Felis silvestris as subspeices following Driscroll et al. (2007), while C. Groves (pers. comm.) regards all these as valid phylogenetic species.”
让读者大人们读了这么多文字,作者惶恐不已,赶紧奉上荒漠猫母子的萌照谢罪,感受一下喵主子的躁动:
雌性荒漠猫与其两只幼崽。拍摄 / 山水自然保护中心,时间 / 2018年
作者:陈怀庆。北京大学动物学博士生,清华大学生命科学学院本科毕业,山水自然保护中心顾问。
编辑 / 山水自然保护中心 彭聪(实习生)
参考文献:
Alphonse Milne-Edwards. (1892). Observations sur les mammifères du Thibet. Revue Générale Des Sciences Pures et Appliquées, Tome III, 670–671.
De Queiroz, K. (2005). Ernst Mayr and the modern concept of species. Proceedings of the National Academy of Sciences, 102(suppl 1), 6600–6607.
De Queiroz, K. (2007). Species concepts and species delimitation. Systematic Botany, 56(6), 879–886.
Driscoll, C., Menotti-Raymond, M., Roca, A. L., Hupe, K., Johnson, W. E., Geffen, E., … Macdonald, D. W. (2007). The Near Eastern origin of cat domestication. Science (New York, N.Y.), 317(5837), 519–23.
Ellerman, J. R., & Morrison-Scott, T. C. S. (1951). Checklist of Palaearctic and Indian mammals, 1758-1946. Printed by order of the Trustees of the British Museum.
Groves, C. P. (1980). The Chinese mountain cat (Felis bieti). Carnivore 3 (), 5–41.
Heptner, V. G., & Sludskii, A. A. (1992). Mammals of the Soviet Union, Carnivora (hyaenas and cats), Vol. II, Part 2. EJ Brill, Leiden, the Netherlands.
Humboldt-universit, A. G., Khaleghi, A., Persian, H., Heritage, W., & Ghadirian, T. (2016). The status of wildcat in Iran - a crossroad of subspecies? Cat News, (November), 62.
Johnson, W. E., Eizirik, E., Pecon-slattery, J., Murphy, W. J., Antunes, A., Teeling, E., & Brien, S. J. O. (2006). The late Miocene radiation of modern Felidae: a genetic assessment. Science, 127(1994), 1–6.
Kitchener, A. C., Breitenmoser-Würsten, C., Eizirik, E., Gentry, A., Werdelin, L., Wilting, A., & Yamaguchi, N. (2017). A revised taxonomy of the Felidae: The final report of the Cat Classification Task Force of the IUCN Cat Specialist Group. Cat News.
Kitchener, A. C., & Rees, E. E. (2009). Modelling the dynamic biogeography of the wildcat: implications for taxonomy and conservation. Journal of Zoology, 279(2), 144–155.
Le Roux, J. J., Foxcroft, L. C., Herbst, M., & MacFadyen, S. (2015). Genetic analysis shows low levels of hybridization between African wildcats (Felis silvestris lybica) and domestic cats (F. s. catus) in South Africa. Ecology and Evolution, 5(2), 288–99.
Li, G., Davis, B. W., Eizirik, E., & Murphy, W. J. (2016). Phylogenomic evidence for ancient hybridization in the genomes of living cats (Felidae). Genome Research, 26(1), 1–11.
Mayden, R. L. (1997). A hierarchy of species concepts: the denouement in the saga of the species problem.
Mayr, E. (1942). Systematics and the origin of species, from the viewpoint of a zoologist. Harvard University Press.
Ottoni, C., Neer, W. Van, De Cupere, B., Daligault, J., Guimaraes, S., Peters, J., … Geigl, E.-M. (2017). The palaeogenetics of cat dispersal in the ancient world. NATURE ECOLOGY & EVOLUTION, 1.
Pocock, R. I. (1951). Catalogue of the genus Felis.
Sanderson, J., Yin, Y., & Drubgayal, N. (2010). Of the only endemic cat species in China. Cat News, 18–21.
Schreber, J. C. D. von. (1778). Die Säugthiere in Abbildungen nach der Natur mit Beschreibungen (Dritter Theil). Expedition Des Schreber’schen Säugthier- Und Des Esper’schen Schmetterlingswerkes, Erlangen, 397–402:Die wilde Kaze.
Yamaguchi, N., Driscoll, C. A., Kitchener, A. C., Ward, J. M., & Macdonald, D. W. (2004). Craniological differentiation between European wildcats (Felis silvestris silvestris), African wildcats (F. s. lybica) and Asian wildcats (F. s. ornata): Implications for their evolution and conservation. Biological Journal of the Linnean Society, 83(1), 47–63.
Yamaguchi, N., Kitchener, A., Driscoll, C., & Nussberger, B. (2015). Felis silvestris.