INTER-SECTION Volume III - Page 10

| Kim P. Deckers | period, early Homo species, such as Homo habilis and Homo ergaster in brain and body size compared to the earlier Australopithecines (Antón et al. 2014, 3). Larger brain sizes require more energy to maintain and thus more nutrient-dense food packages (Antón et al. 2014, 8; Pontzer, 2012, 347), which were probably attained by an increase in meat-eating (Kaplan et al. 2000, 156). The endurance running hypothesis proposes that long distance running and persistence hunting strategies were adopted by hominins to allow them to compete for meat with other African carnivores. Persistence hunting requires knowledge of animal behaviour, the ability to track, and the necessity of sharing with peers (Pickering and Bunn, 2007, 436) in order to hunt successfully. If the endurance-hunting hypothesis can be proven to be true, this will further our understanding of when increased cognitive and social skills evolved in the hominin lineage. In 2004, the seminal paper by Bramble and Lieberman summarising the anatomical traits necessary for endurance running concluded that the capability to run over long distances and the associated hunting strategies did not evolve until the appearance of Homo erectus at 1.8 million years ago. The authors hypothesised that the ability to role in the dispersal of these creatures into Eurasia (Bramble and Lieberman 2004, 350). However, the validity of the endurance running hypothesis has been questioned by scholars that were unconvinced that the skeletal markers described by Lieberman and Bramble were indicative of increased running (Steudel-Numbers 2006, 451; Steudel-Numbers and remains for many early Homo fossils also made it were present. It has been over 10 years since the Bramble and Lieberman paper was published. Since Australopithecus afarensis (Haile-Selassie et al. 2010, 12121; Ward et al. 2012, 2), Australopithecus sediba (Zipfel et al. 2011, 1417), Homo georgicus/erectus (Lordkipanidze et al. 2007, 305) (Jungers et al. 2009, 539) and Homo naledi (Berger et al. 2015, 5) further evidence in support or against the endurance running hypothesis. This paper aims to re-assess the validity of the endurance running hypothesis in light of these new discoveries. p. 8 | VOL III | INTER-SECTION | 2017 Feature First seen Narrow pelvis* Homo Enlarged illiac pillar Homo erectus Stabilised sacroiliac joint* Homo erectus Expanded surface area for mm. erector spinae origin* Homo erectus Expanded surface area for m. gluteus maximus origin* Homo erectus Long legs Homo erectus Expanded hindlimb joint surface area/robusticity Homo erectus Shorter femo ral neck Homo sapiens Plantar/Longitudinal arch* Homo Close-packed calcaneocuboid joint/cuboid flange Homo habilis Enla rged tuber calcaneus* Homo Permanently adducted hallux Homo habilis Short toes Homo habilis * argued to be beneficial for running efficiency alone Table 1. Lower limb anatomical features related to endurance running (After Bramble and Lieberman 2004, 348). Methodology on the lower limb (tab. 1). This study focuses on several features in the lower limb. The reason for this limitation was threefold: 1) the lower limb is the only part of the body that makes contact with the substrate during locomotion. This makes the lower limb the most likely location where in the morphology of skeletal elements; 2) many of the species under study have associated lower limb skeletal elements; 3) detailed descriptions of lower limb bone morphology and measurable data have been reported in the literature for these skeletal elements. While the pelvis is also involved in locomotion, this bone was excluded from this analysis due to the fact that its morphology is also growth and development within early Homo species (Rosenberg and Trevathan 2005, 164). A subset of the lower limb features described by Bramble and Lieberman (2004, 348) was analysed in this study (tab. 2), as these features were most commonly reported in the literature.