Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig 04103, Germany.
Department of Anthropology, Florida State University, Tallahassee, FL 32310, USA.
Sci Adv. 2020 Apr 1;6(14):eaaz4729. doi: 10.1126/sciadv.aaz4729. eCollection 2020 Apr.
Human brains are three times larger, are organized differently, and mature for a longer period of time than those of our closest living relatives, the chimpanzees. Together, these characteristics are important for human cognition and social behavior, but their evolutionary origins remain unclear. To study brain growth and organization in the hominin species more than 3 million years ago, we scanned eight fossil crania using conventional and synchrotron computed tomography. We inferred key features of brain organization from endocranial imprints and explored the pattern of brain growth by combining new endocranial volume estimates with narrow age at death estimates for two infants. Contrary to previous claims, sulcal imprints reveal an ape-like brain organization and no features derived toward humans. A comparison of infant to adult endocranial volumes indicates protracted brain growth in , likely critical for the evolution of a long period of childhood learning in hominins.
人类大脑的体积比我们最亲近的现存亲属——黑猩猩大 3 倍，其组织结构也不同，并且需要更长的时间才能发育成熟。这些特征对于人类的认知和社会行为都很重要，但它们的进化起源仍不清楚。为了研究 300 多万年前的人属物种的大脑生长和组织，我们使用传统和同步辐射计算机断层扫描技术对 8 个头骨化石进行了扫描。我们从脑内印痕推断出大脑组织的关键特征，并通过将新的脑内体积估算值与两个婴儿的死亡年龄估算值结合起来，探索了大脑生长的模式。与之前的说法相反，脑回印痕揭示了一种类猿的大脑组织，没有任何向人类进化的特征。婴儿和成人脑内体积的比较表明，在 中存在延长的大脑生长，这可能对人属物种中长时间的儿童学习进化至关重要。
