Research: New Postcranial Fossils of Australopithecus Afarensis and A. anamensis

这项研究的目的是描述和分析最早的人类祖先的新化石。 这些化石包括来自埃塞俄比亚和肯尼亚的至少两个物种的大量躯干和四肢骨骼，即南方古猿阿法种和南方古猿阿纳马种。 这些新的颅后化石将揭示这些早期原始人类对姿势和运动的适应。 37个新的A.在埃塞俄比亚的Hadar发现了afarensis，可追溯到大约350 - 300万年前。这些化石包括最早发现的A. afarensis lunate; a large A. afarensis个体，相关的早期南方古猿尺骨和掌骨，以及许多其他发现。 在肯尼亚，发现了一个南方古猿（Australopithecus sp. indet）的部分手骨骼和相关的脚趾指骨，发现于西图尔卡纳的南特克韦尔（South Turkwel），其年代与此相似。这些是已知的第一个与早期南方古猿相关的手骨。 肯尼亚研究小组最近还发现了已知最早的南方古猿物种的第一个胫骨和指骨，来自Kanapoi的南方古猿Anamensis，可追溯到400万年前。 这些新化石将有助于解决关于早期原始人类运动性质的争论。 古人类学家一致认为，我们最早的祖先的第一个主要的适应性转变是采用直立，两足运动。 然而，关于树栖性对最早的原始人有多重要，仍有相当多的争论。 准确解释我们最早祖先的运动行为对于理解人类起源至关重要。 这项研究将为早期原始人类的运动适应提供新的信息，因为它提供了（1）新的A。来自以前未取样的解剖区域和功能复合体的阿法种化石，（2）最早的南方古猿种A.（3）首次分析了我国南方古猿的分布比例和分布区域;（4）在解释运动行为时考虑解剖学特征的发育基础。 拟议研究的目标是：（1）提供所有新化石的详细解剖描述和照片，（2）收集广泛的标准公制、非公制和长骨骨干横截面数据，这些数据反映了南方古猿、现代人类和猿骨骼的大样本运动适应性，（3）对猿类和人科动物骨骼上肌肉附着点的解剖及其对肌肉瘢痕形成的影响进行初步研究; afarensis、阿法囊藻A. anamensis和其他南方古猿物种来评估我们最早祖先的运动进化。

The purpose of this study is to describe and analyze new fossils of the earliest human ancestors. These fossils include numerous torso and limb bones of at least two species, Australopithecus afarensis and Australopithecus anamensis, from Ethiopia and Kenya. These new postcranial fossils will reveal adaptations to posture and locomotion in these early hominids. Thirty-seven new postcranial bones of A. afarensis have been discovered from Hadar, Ethiopia, dated to about 3.5 - 3 million years ago. These fossils include the first-known A. afarensis lunate; talus of a large A. afarensis individual, associated early australopithecine ulna and metacarpals, and many other discoveries. In Kenya, a partial hand skeleton and associated toe phalanx of Australopithecus sp. indet were recovered from South Turkwel, West Turkana, and are dated to a similar time period. These are the first associated hand bones known for any early australopithecine. The Kenyan team also has recently discovered the first tibia and phalanx of the earliest known australopithecine species, Australopithecus anamensis from Kanapoi, dated to 4.0 mya. These new fossils will help resolve debate over the nature of early hominid locomotion. Paleoanthropologists agree that the first major adaptive shift of our earliest ancestors was the adoption of upright, bipedal locomotion. However, considerable debate remains about how important arboreality remained for the earliest hominids. An accurate interpretation of the locomotor behavior of our earliest ancestors is critical for understanding human origins. The proposed study will provide novel information about early hominid locomotor adaptations because it provides (1) New A. afarensis fossils from anatomical regions and functional complexes not previously sampled, (2) New fossils of the earliest australopithecine species, A. anamensis, (3) First analyses of the proportions and certain regions of the A. afarensis forelimb which have never been analyzed in detail, and (4) A consideration of the developmental basis of anatomical features when interpreting locomotor behavior. Objectives of the proposed research are to: (1) Provide detailed anatomical descriptions and photographs of all new fossils, (2) Collect extensive standard metric, nonmetric, and long bone shaft cross-sectional data that reflect locomotor adaptation on a large sample of australopithecine, modern human and ape skeletons, (3) Conduct a pilot study on the anatomy of muscle insertions and its effect on the development of muscle scars on bones in apes and hominids, and (4) Test hypotheses of locomotion in A. afarensis, A. anamensis and other australopithecine species to assess locomotor evolution in our earliest ancestors.