While a lot of scholarship identifies Mary Leakey as a wife, mother, and half of a husband and wife research team, one of her most influential and predominant contributions to the field of paleoanthropology serves as an excellent testament the path that Leakey forged for herself: the famous Laetoli footprints.
In 1978, while working in Laetoli, Tanzania, Leakey discovered the fossilized footprints of three hominin individuals. There is one large set of footprints, a medium set of footprints, and potentially a smaller set of footprints on top of the larger set of footprints, alluding that the smallest individual walked slightly behind the largest and walked in their tracks. Many assume that a family unit of australopiths created these tracks, but a large degree of uncertainty still surrounds the Laetoli prints (Hay & Leakey, 1982).
The wide breadth of Leakey’s scholarship on the Laetoli footprints embodies the incredible diversity of expertise Leakey brought to the field of paleoanthropology. Some of her work was quite technical, such as her analyses of volcanic ash fossilization and soil conditions from Oldvuvai Gorge, (Hay & Leakey, 1982). Other articles explained the extensive artifact findings at Laetoli (Leakey, 1984). Most notably, her thorough analysis of the prints themselves strongly suggested that the prints were created through upright bipedal walking (Leakey & Harris, 1987), a finding that has been replicated by recent research as well (Raichlen et al., 2010). The dating of the fossils themselves also provided key evolutionary insight into the development of bipedalism. The prints were dated to approximately 3.6 million years ago. As Leakey pointed out in her research on them, the earliest stone tools that were discovered at the Olduvai Gorge were only 1.9 million years old (Hay & Leakey, 1982). At the time of Leakey’s discovery, a prominent school of evolutionary thought was that tool use and hunting drove the evolution of bipedal walking to free up the hands for these activities. The Laetoli prints, however, debunk this theory, as they present direct evidence that bipedal walking occurred about a million and a half years before tool use.
Although Leakey did not identify or engage with feminism, her very presence as a prominent researcher in this male-dominated profession at the time serves as inspiration for many women in the field of paleoanthropology, whilst simultaneously opening the door for other trowelblazers after her (Hager, 1997). Leakey’s independent discovery and research on the Laetoli prints has not only stitched together the steps of our evolutionary history, but also forged a path of curiosity and expertise for women in anthropology.
Written by Gina Nerone, Lacey Alexander, and Mary Mohr for the course “Gender and Human Evolution”, taught by Caroline VanSickle and published as part of the Women in Paleoanthropology special collection.
Hay, R. L., & Leakey, M. D. (1982). The fossil footprints of Laetoli. Scientific American, 246, 50-57.
Hager, L. D. (1997). Sex and gender in paleoanthropology. In L. Hager (Ed.), Women in Human Evolution, (pp. 1-28). New York, NY: Routledge.
Leakey, M. D. (1984). Disclosing the past. Garden City, NY: Doubleday.
Leakey, M. D., & Harris, J. M. (Eds.). (1987). Laetoli, a Pliocene site in northern Tanzania. Oxford, UK: Clarendon Press.
Raichlen, D. A., Gordon, A. D., Harcourt-Smith, W. E., Foster, A. D., & Haas Jr, W. R. (2010). Laetoli footprints preserve earliest direct evidence of human-like bipedal biomechanics. PLoS One, 5(3), e9769.