MNK Skull is one of the most significant archaeological sites in Olduvai Gorge, particularly due to the previous discovery of human fossils referred to in the paper where the Homo habilis taxon was originally defined. An important archaeological assemblage is contained in the same horizon as the hominin fossils, constituting the last evidence of both Homo habilis remains and handaxe-free tool kits in the Olduvai Gorge sequence. Our excavations at the site are the first to be conducted since the original work in the 1960s, and sought to refine the archaeological context wherein the Homo habilis remains were discovered. Chronostratigraphic results place the MNK Skull sequence in Middle Bed II prior to deposition of Tuff IIB. The assemblage was deposited near the shoreline, as Palaeolake Olduvai withdrew into the basinal depocentre, and fossils and stone tools were subjected to significant post-depositional processes. The assemblage was affected by mudflow deposits that buried and preserved the assemblage but also entrained surficial bone and lithic elements into the flow. Rather than an occupation site as originally interpreted, the assemblage is better understood as a background deposit, possibly accumulated on an unconformity surface over a long period of time. The stone tool assemblage is typical of the Oldowan, with no technological elements announcing the appearance of the Acheulean, which is well attested to across the Olduvai sequence in post-Tuff IIB times. Our results highlight that, with an approximate age of circa 1.67 Ma, MNK Skull stands as a key site to understand the late Oldowan and the disappearance of Homo habilis in East Africa.

MNK头骨是奥尔杜瓦伊峡谷中最重要的考古遗址之一，特别是由于该文献先前提到的人类化石的发现是最初定义了人类同源生物群的地方。一个重要的考古组合与人猿化石处在同一水平线上，构成了Olduvai峡谷序列中的哈比人遗骸和无手斧工具包的最后证据。我们在现场发掘是自20世纪60年代的原创作品将进行了第一次，并寻求改进考古方面，其中能人遗体被发现。时序地层结果将MNK头骨序列置于Tuff IIB沉积之前的中层床II中。整个沉积物堆积在海岸线附近，奥尔德瓦古湖撤回盆地沉积中心，化石和石器工具经历了大量的沉积后过程。该组合受到泥浆流沉积物的影响，这些沉积物掩埋并保留了该组合物，但也将表层的骨和石质元素带入了流中。更好的理解是该组合不是本底解释的占领地点，而是本底沉积物，可能会长时间堆积在不整合表面上。石材工具组合是Oldowan的典型代表，没有任何技术元素可以宣布Acheulean的外观，在Tuff IIB后的时代中，这在Olduvai序列中得到了很好的证明。我们的研究结果表明，MNK Skull的年龄大约为1.67 Ma，是了解已故的Oldowan和黑猩猩消失的关键地点。东非的人类。