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鬣狗科动物曾是一个数量十分可观的群体,在5百万年前曾达到演化的鼎盛时期,留下已鉴定化石种100余种.现生的鬣狗科动物仅有4种,仅分布在亚洲和非洲部分地区.由于该科动物演化至今种类剧减、分布区退缩,部分化石种与现生种的谱系演化关系尚不明确,因此成为古生物学家和进化生物学家关注的生物类群之一.采用现代分子生物学方法,提取扩增河北秦皇岛灵仙洞中鬣狗类化石的线粒体基因组古DNA片段,通过与基因库中已有鬣狗科动物各属种同源序列的对比分析,从分子水平确定该化石为斑鬣狗化石;基于古DNA序列数据构建的系统进化树显示,该地的斑鬣狗个体与我国东北地区及俄罗斯的化石斑鬣狗具有较近的亲缘关系,而与西欧洞穴鬣狗及非洲现生斑鬣狗亲缘关系较远,显示出斑鬣狗演化的分子地理谱系.
Once a 5 million year old population, the hyena, once the epicenter of evolution, has survived more than 100 species of fossilized species, and there are only 4 species of hyena in existence, only in Asia And some parts of Africa, which have become one of the biological groups concerned by paleontologists and evolutionary biologists due to the sharp decline of species, the shrinking of the distribution area and the evolution of pedigree of some fossil species and the present species. Using modern methods of molecular biology, the ancient DNA fragment of mitochondrial genome of hyenas fossils in Lingxian Cave, Qinhuangdao, Hebei Province was extracted and amplified, and compared with the homologous sequences of various species of hyena in the gene bank, The fossil is a crocuta fossil. Phylogenetic tree based on ancient DNA sequence data shows that crested hyenas in this area have relatively close genetic relationship with fossil spot hyenas in northeastern China and Russia. However, Spotted hyenas are more distantly related and show the molecular phylogeny of crocodilian evolution.