9: Early Hominins

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Kerryn Warren, Ph.D., University of Cape Town

Lindsay Hunter, Ph.D., University of Witwatersrand

Navashni Naidoo, M.Sc., University of Cape Town

Silindokuhle Mavuso, M.Sc., University of Witwatersrand

Kimberleigh Tommy, M.Sc., University of Witwatersrand

Rosa Moll, M.Sc., University of Witwatersrand

Nomawethu Hlazo, M.Sc., University of Cape Town

Learning Objectives

Define what is meant by “hominin”.
Understand what is meant by “derived” and “primitive” traits and why this is relevant for understanding early hominin evolution.
Understand changing paleoclimates and paleoenvironments during early human evolution, and contextualize them as potential factors influencing adaptations during this time.
Describe the anatomical changes associated with bipedalism in early hominins and the implications for changes in locomotion.
Describe the anatomical changes associated with dentition in early hominins and their implication for diet in the Plio-Pleistocene.
Describe early hominin genera and species, including their currently understood dates and geographic expanses and what we know about them.
Describe the earliest stone tool techno-complex and what it implies about the transition from early hominins to our genus.

About the Authors

Kerryn Warren, Ph.D.

University of Cape Town, kerryn.warren@gmail.com

Kerryn Warren

Kerryn Warren is a postdoctoral researcher at the University of Cape Town. She lectures on archaeology and human evolution. Her research interests include identifying hybridization in the hominin fossil record, stemming from research from her Ph.D., and understanding the evolution of education in South African schools. She is also currently one of the new “Underground Astronauts” selected to excavate Homo naledi remains from the Rising Star Cave System in the Cradle of Humankind. She is passionate about education and science communication.

Lindsay Hunter, Ph.D.

University of Witwatersrand

Lindsay Hunter

Lindsay Hunter is a trained paleoanthropologist who uses her more than 15 years of experience to make sense of the distant past of our species in ways that can help us to build a better future. She received her master’s degree in biological anthropology from the University of Iowa and is completing her Ph.D. in archaeology at the University of the Witwatersrand. She has studied fossil and human bone collections across five continents with major grant support from the National Science Foundation (United States) and the Wenner-Gren Foundation for Anthropological Research. More recently she developed and led the National Geographic “Umsuka” Public Palaeoanthropology Project in South Africa with support from the National Geographic Society and private donors. She now works as the Community Relations and Development Director for the Center for Academic Research and Training in Anthropogeny (CARTA) at UCSD.

Navashni Naidoo, M.Sc.

University of Cape Town

Navashni Naidoo

Navashni Naidoo is a researcher at Nelson Mandela University, lecturing on physical geology. Her research interests include developing paleoenvironmental proxies suited to the African continent, behavioral ecology, and engaging with community-driven archaeological projects. She has excavated at Stone Age sites across South Africa and East Africa.

Silindokuhle Mavuso, M.Sc.

University of Witwatersrand

Silindokuhle Mavuso

Silindokuhle has always been curious about the world around him and how it has been shaped. He is a Ph.D. Candidate at the University of Witwatersrand (Wits) conducting palaeoenvironmental reconstruction and change of the northeastern Turkana Basin’s Pleistocene sequence. Silindokuhle begun his education with a B.Sc. (geology, archaeology, and environmental and geographical sciences) from the University of Cape Town before moving to Wits for a B.Sc. Honors (geology and palaeontology) and M.Sc. in geology. During this time, he has gained more training as a Koobi Fora Fieldschool fellow (Kenya) as well as an Erasmus Mundus scholar (France). Silindokuhle is a Plio-Pleistocene geologist with a specific focus on identifying and explaining past environments that are associated with early human life and development through time. He is interested in a wide range of disciplines such as micromorphology, sedimentology, geochemistry, geochronology, and stratigraphy. He has worked with teams from significant eastern and southern African hominid sites including Elandsfontein, Rising Star, Sterkfontein, Gondolin, Laetoli, Olduvai, and Koobi Fora. He plans to extend his knowledge from both parts of the continent to assist the better understanding of how we as humans came to being.

Kimberleigh Tommy, M.Sc.

University of Witwatersrand

Kimberleigh Tommy

Kimberleigh Tommy is currently a Ph.D. candidate in biological anthropology at the Human Variation and Identification Research Unit of the School of Anatomical Sciences at the University of Witwatersrand. Her current research focuses on the evolution and biomechanical implications of bipedal walking through analyses of trabecular bone structure in the joints of the lower limb. Kimberleigh was awarded her Master of Science (M.Sc.) degree with distinction (and no corrections) from the University of the Witwatersrand, specializing in palaeoanthropology and functional morphology in 2018. Her research interests include trabecular structure, functional morphology, primate locomotion, ontogenetic development of gait, biomechanics, and joint pathologies.

Rosa Moll, M.Sc.

University of Witwatersrand

Rosa Moll

Rosa Moll is an archaeology Ph.D. candidate at the University of Witwatersrand. She focuses on Earlier Stone Age core reduction strategies of east Africa and south Africa and received her M.Sc. with distinction in the same field. She is interested in how stool tool technological behaviors correspond with cognitive human evolution. In 2018 she was awarded the Baldwin Fellowship from the Leakey Foundation as part of her Ph.D.

Nomawethu Hlazo, M.Sc.

University of Cape Town

Nomawethu Hlazo

Nomawethu Hlazo is a student at the University of Cape Town currently undergoing her Doctoral Degree. She completed her undergraduate degree in biochemistry and archaeology. Since then her postgraduate studies have focused on the genus Paranthropus and the variation that exists between and within species. Following the fossil species, she has concentrated on the study of geometric morphometrics and will follow new techniques such as paleoproteomics to investigate not only shape change but contributions of evolutionary processes and ecological niches occupied by the genus Paranthropus. Since the start of her research with Paranthropus, she has worked at several sites, not only in the Cradle of Humankind World Heritage Site in South Africa but also in Kenya. Her research has shown that this genus is highly diverse and more variable than we expected. After completion of her master’s (with distinction), she has been able to show the contributions of both natural selection and genetic drift and their roles in shaping Paranthropus craniomandibular variation.

For Further Exploration

The Smithsonian website hosts descriptions of fossil species, an interactive timeline and much more! It is a highly recommended website. http://humanorigins.si.edu/evidence

The Maropeng Museum website hosts a wealth of information regarding South African Fossil Bearing sites in the Cradle of Humankind. https://www.maropeng.co.za/content/page/human-evolution

This quick comparison between Homo naledi and Australopithecus sediba from the Perot Museum: https://perot-museum.imgix.net/2019-08-naledi-sediba-quick-comparison.pdf

This explanation of the braided stream by the Perot Museum: https://www.dropbox.com/s/l1d2hv42psj21y9/Braided%20Stream-1920.mp4?dl=0

A collation of 3-D files for visualizing (or even 3-D printing) for homes, schools, and universities: https://www.hetmp.com/

PBS learning materials, including videos and diagrams of the Laetoli footprints, bipedalism, and fossils: https://www.pbslearningmedia.org/resource/tdc02.sci.life.evo.lp_humanevo/human-evolution/

A wealth of information from the Australian Museum website, including species descriptions, family trees, and explanations of bipedalism and diet: https://australianmuseum.net.au/learn/science/human-evolution/

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Acknowledgments

All of the authors in this section are students and early career researchers in paleoanthropology and related fields in South Africa (or at least have worked in South Africa). We wish to thank everyone who supports young and diverse talent in this field and would love to further acknowledge black, African, and female academics who have helped pave the way for us.

Figure Attributions

Figure 9.1 IMG_1696 Great Rift Valley by Ninara is used under a CC BY 2.0 License.

Figure 9.2 Clades original to Explorations: An Open Invitation to Biological Anthropology by Katie Nelson is under a CC BY-NC 4.0 License.

Figure 9.3 CO₂ increase since the Industrial Revolution by NASA, original from Luthi, D., et al.. 2008; Etheridge, D.M., et al. 2010; Vostok ice core data/J.R. Petit et al.; NOAA Mauna Loa CO₂ record is in the public domain and used within NASA guidelines on re-use.

Figure 9.4 African savannah @ Masai Mara (21308330314) by Leo Li from Hong Kong is used under a CC BY 2.0 License.

Figure 9.5 Skeleton of human (1) and gorilla (2), unnaturally sketched by unknown from Brehms Tierleben, Small Edition 1927 is in the public domain.

Figure 9.6 Skeletal comparisons between modern humans and non-obligate bipeds original to Explorations: An Open Invitation to Biological Anthropology is under a CC BY-NC 4.0 License.

Figure 9.7a Sahelanthropus tchadensis: TM 266-01-060-1 anterior view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.7b Sahelanthropus tchadensis: TM 266-01-060-1 posterior view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.7c Sahelanthropus tchadensis: TM 266-01-060-1 inferior view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.7d Sahelanthropus tchadensis: TM 266-01-060-1 lateral left view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.8a Ardipithecus ramidus Skull by ©BoneClones is used by permission and available here under a CC BY-NC 4.0 License.

Figure 9.8b Artist’s rendition of “Ardi” skeleton by ©BoneClones is used by permission and available here under a CC BY-NC 4.0 License.

Figure 9.9 Adult human teeth by Genusfotografen (Tomas Gunnarsson) through Wikimedia Sverige Wikimedia Sverige is used under a CC BY-SA 4.0 License.

Figure 9.10 Paranthropus bonsei compared to Homo sapiens by Constantino, Paul J. is used under a CC BY-SA 4.0 License.

Figure 9.11 Australopithecus anamensis: KNM-KP 29281 occlusal view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.12a Australopithecus afarensis, “Lucy,” adult female. Reconstruction based on AL-288-1 by artist John Gurche, front view close-up. by Smithsonian [exhibit: Reconstructed Faces, What does it mean to be human?] is copyrighted and used for educational and noncommercial purposes as outlined by the Smithsonian.

Figure 9.12b Australopithecus afarensis, adult male. Reconstruction based on AL444-2 by John Gurche by Smithsonian [exhibit: Reconstructed Faces, What does it mean to be human?] is copyrighted and used for educational and noncommercial purposes as outlined by the Smithsonian.

Figure 9.13 Lucy blackbg (AL 288-1, Australopithecus afarensis, cast from Museum national d’histoire naturelle, Paris) by 120 is used under a CC BY-SA 3.0 License.

Figure 9.14a Kenyanthropus platyops KNM WT 40000 anterior view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.14b Kenyanthropus platyops KNM WT 40000 superior view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.14c Kenyanthropus platyops KNM WT 40000 lateral left view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.14d Kenyanthropus platyops KNM WT 40000 inferior view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.15a australopithecus africanus: Taung 1 anterior view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.15b australopithecus africanus: Taung 1 lateral right view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.16a Australopithecus africanus Sts 5 anterior view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.16b Australopithecus africanus Sts 5 posterior view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.16c Australopithecus africanus Sts 5 superior view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.16d Australopithecus africanus Sts 5 lateral right view by eFossils is copyrighted and used for noncommercial purposes as outlined by eFossils.

Figure 9.17 Australopithecus africanus. Reconstruction based on STS 5 by John Gurche by Smithsonian [exhibit: Reconstructed Faces, What does it mean to be human?] is copyrighted and used for educational and noncommercial purposes as outlined by the Smithsonian.

Figure 9.18 Australopithecus sediba, photo by Brett Eloff, courtesy Profberger and Wits University is used under a CC BY-SA 4.0 License.