The ‘mosaic habitat’ concept in human evolution: past and present

Abstract

The habitats preferred by hominins and other species are an important theme in palaeoanthropology, and the ‘mosaic habitat’ (also referred to as habitat heterogeneity) has been a central concept in this regard for the last four decades. Here we explore the development of this concept – loosely defined as a range of different habitat types, such as woodlands, riverine forest and savannah within a limited spatial area – in studies of human evolution over the last 60 years or so. We outline the key developments that took place before and around the time when the term ‘mosaic’ came to wider palaeoanthropological attention. To achieve this, we used an analysis of the published literature, a study of illustrations of hominin evolution from 1925 onwards and an email survey of senior researchers in palaeoanthropology and related fields. We found that the term ‘mosaic’ starts to be applied in palaeoanthropological thinking during the 1970s due to the work of a number of researchers, including Karl Butzer and Glynn Isaac, with the earliest usage we have found of ‘mosaic’ in specific reference to hominin habitats being by Adriaan Kortlandt (1972). While we observe a steady increase in the numbers of publications reporting mosaic palaeohabitats, in keeping with the growing interest and specialisation in various methods of palaeoenvironmental reconstruction, we also note that there is a lack of critical studies that define this habitat, or examine the temporal and spatial scales associated with it. The general consensus within the field is that the concept now requires more detailed definition and study to evaluate its role in human evolution.

Keywords:

• habitat heterogeneity
• time-averaging
• habitat variability
• Savannah Hypothesis
• palaeoenvironmental reconstruction
• palaeoecology.

ACKNOWLEDGEMENTS

We would like to thank numerous colleagues who shared their ideas, pictures, recollections and insights about the mosaic habitat concept, including Stanley Ambrose, Peter Andrews, René Bobe, Susan Cachel, John de Vos, Clive Gamble, Alan Gentry, Colin Groves, Ralph Holloway, Don Johanson, Clifford Jolly, Jonathan Kingdon, Owen Lovejoy, Bill McGrew, James Ohman, John Olsen, David Pilbeam, Peter Schmid, Jeanne Sept, Chris Stringer, Ian Tattersall, Francis Thackeray, Tim White, Edward O. Wilson, Milford Wolpoff and Richard Wrangham. Goran Strkalj made useful comments on an earlier version of this manuscript. We would like to thank the Editor Margaret Avery and two anonymous referees for their comments which have improved this manuscript.

Notes

1. Mayr (1982) records that the term ‘mosaic evolution’ was coined in 1954 by Gavin de Beer with reference to the genus Archaeopteryx (although the ideas had been around for many years before that) and it was being used in the palaeoanthropological literature by the late 1950s (e.g. Le Gros Clark, 1959b) in the context of a mix of ‘advanced’ and ‘primitive’ features in the same fossil. Thus, the use of ‘mosaic evolution’ predates the use of ‘mosaic habitat’ by some decades.

Additional information

Funding

This work is part of the Quantifying the Mosaic project, funded by the Leverhulme Trust [grant number RPG-2012-472] and we thank them for their support.