The ecology of Australopithecus anamensis in the early Pliocene of Kanapoi, Kenya

René Bobe; Fredrick Kyalo Manthi; Carol V Ward; J Michael Plavcan; Susana Carvalho

doi:10.1016/j.jhevol.2019.102717

The ecology of Australopithecus anamensis in the early Pliocene of Kanapoi, Kenya

J Hum Evol. 2020 Mar:140:102717. doi: 10.1016/j.jhevol.2019.102717. Epub 2020 Jan 6.

Authors

René Bobe¹, Fredrick Kyalo Manthi², Carol V Ward³, J Michael Plavcan⁴, Susana Carvalho⁵

Affiliations

¹ Primate Models for Behavioural Evolution Lab, Institute of Cognitive & Evolutionary Anthropology, School of Anthropology, University of Oxford, Oxford, UK; Gorongosa National Park, Sofala, Mozambique; Interdisciplinary Centre for Archaeology and Evolution of Human Behaviour (ICArEHB), Universidade Do Algarve, Faro, Portugal. Electronic address: renebobe@gmail.com.
² Department of Earth Sciences, National Museums of Kenya, Nairobi, Kenya.
³ Department of Pathology and Anatomical Sciences, University of Missouri, Columbia, MO, USA.
⁴ Department of Anthropology, University of Arkansas, Fayetteville, AR, USA.
⁵ Primate Models for Behavioural Evolution Lab, Institute of Cognitive & Evolutionary Anthropology, School of Anthropology, University of Oxford, Oxford, UK; Gorongosa National Park, Sofala, Mozambique; Interdisciplinary Centre for Archaeology and Evolution of Human Behaviour (ICArEHB), Universidade Do Algarve, Faro, Portugal; Centre for Functional Ecology, University of Coimbra, Coimbra, Portugal.

PMID: 31916996
DOI: 10.1016/j.jhevol.2019.102717

Abstract

Australopithecus anamensis is a pivotal species in human evolution. It is likely to be the direct ancestor of Australopithecus afarensis and the species that may have given rise to the Homo and Paranthropus lineages. It had a suite of adaptations for habitual bipedalism and a diet that differed from that of earlier hominin species. Under what environmental and ecological conditions did this suite of adaptations arise? The early Pliocene site of Kanapoi in the Lake Turkana Basin of Kenya has the largest sample of A. anamensis in eastern Africa and a rich record of fossil vertebrates. Most Kanapoi fossils are chronologically well constrained by radiometrically dated tephras between the ages of 4.2 and 4.1 million years ago. Sedimentological, isotopic, and faunal data indicate that the environments of Kanapoi during the early Pliocene had a complex range of vegetation types that included closed woodlands, shrubs, and grasslands near a river (for most of the sequence) or lake. These were dynamic landscapes that could shift rapidly from fluvial to lacustrine conditions, and then back. Australopithecus anamensis shared its environments with at least 10 species of very large herbivores, which undoubtedly played a major role in modifying the landscape by opening wooded areas and providing pathways for bipedal hominins. Hominins may have competed for terrestrial resources with abundant suids (Nyanzachoerus and Notochoerus) and for arboreal resources with monkeys (Parapapio being the most common cercopithecid). Kanapoi had a formidable group of predators that included a very abundant species of hyena (Parahyaena howelli), two sabre-tooth felids (Dinofelis and Homotherium), a giant otter (Enhydriodon cf. dikikae), and three species of crocodiles. Various measures of abundance indicate that A. anamensis was an important component of the Kanapoi early Pliocene ecosystems, and that its key adaptations allowed this species to thrive in complex and dynamic landscapes.

Keywords: Faunal analysis; Hominin paleoecology; Paleoenvironments; eastern Africa.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Animals
Biological Evolution*
Fossils
Hominidae / physiology*
Kenya
Life History Traits*