靈長(zhǎng)類(lèi)的化石記錄很稀少，仍然存在實(shí)質(zhì)性的缺口,。其中一個(gè)缺口是“舊世界”的猴子與“新世界”高等靈長(zhǎng)類(lèi)內(nèi)的類(lèi)人猿和人類(lèi)的分化,。這種分化以前僅限于“非洲-阿拉伯大陸”的漸新世，但在沙特西北一個(gè)新的,、處在進(jìn)化樹(shù)根部的狹鼻猿的發(fā)現(xiàn)縮小了這個(gè)缺口,。
>>>借著上海世博會(huì)的良好契機(jī)，"第一屆腫瘤基礎(chǔ)和轉(zhuǎn)化醫(yī)學(xué)國(guó)際研討會(huì)"將于2010年10月13日在中國(guó)上海盛大開(kāi)幕,，這將為廣大活躍在腫瘤基礎(chǔ)和轉(zhuǎn)化醫(yī)學(xué)第一線的科研工作者提供一個(gè)互動(dòng)交流的平臺(tái),。
會(huì)議官方網(wǎng)站：www.cancerasia.org
沙特發(fā)現(xiàn)的這個(gè)材料來(lái)自距今約2800萬(wàn)年前的漸新世中期，它的狹鼻猿分化特征非常少,，說(shuō)明“舊世界”的猴子與“新世界”的類(lèi)人猿之間的分化發(fā)生在那個(gè)時(shí)期之后,。本期封面所示為頭蓋骨的前部,，其犬齒和上顎寬臼齒都在原處。頭蓋骨的大小表明這是一個(gè)中等大小的靈長(zhǎng)類(lèi),，體重在15公斤和20公斤之間,。(生物谷Bioon.net)
生物谷推薦原文出處：
Nature doi:10.1038/nature09094
New Oligocene primate from Saudi Arabia and the divergence of apes and Old World monkeys
Iyad S. Zalmout1, 2；William J. Sanders1, 3,；Laura M. MacLatchy1, 3,；Gregg F. Gunnell1；Yahya A. Al-Mufarreh4,；Mohammad A. Ali4,；Abdul-Azziz H. Nasser4；Abdu M. Al-Masari4,；Salih A. Al-Sobhi4,；Ayman O. Nadhra4；Adel H. Matari4,；Jeffrey A. Wilson1, 2,；Philip D. Gingerich1, 2, 3
It is widely understood that Hominoidea (apes and humans) and Cercopithecoidea (Old World monkeys) have a common ancestry as Catarrhini deeply rooted in Afro-Arabia1, 2, 3, 4. The oldest stem Catarrhini in the fossil record are Propliopithecoidea, known from the late Eocene to early Oligocene epochs (roughly 35–30?Myr ago) of Egypt, Oman and possibly Angola5, 6, 7, 8, 9, 10. Genome-based estimates for divergence of hominoids and cercopithecoids range into the early Oligocene11; however, the mid-to-late Oligocene interval from 30 to 23?Myr ago has yielded little fossil evidence documenting the morphology of the last common ancestor of hominoids and cercopithecoids, the timing of their divergence, or the relationship of early stem and crown catarrhines. Here we describe the partial cranium of a new medium-sized (about 15–20?kg) fossil catarrhine, Saadanius hijazensis, dated to 29–28?Myr ago. Comparative anatomy and cladistic analysis shows that Saadanius is an advanced stem catarrhine close to the base of the hominoid–cercopithecoid clade. Saadanius is important for assessing competing hypotheses about the ancestral morphotype for crown catarrhines1, 12, 13, 14, early catarrhine phylogeny12, 15 and the age of hominoid–cercopithecoid divergence11. Saadanius has a tubular ectotympanic but lacks synapomorphies of either group of crown Catarrhini, and we infer that the hominoid–cercopithecoid split happened later, between 29–28 and 24 Myr ago.
