Research

I am a paleoanthropologist primarily interested in the form and function of the hominin pelvis and its effects on parturition. My research concentrates on the evolutionary pressures that have shaped pelvic morphology and determined the mechanisms of modern human birth. I am especially interested in the health burdens that pregnancy and delivery place on women and how and why these burdens evolved. This has prompted my investigations into the “obstetrical dilemma” which questions why birth in our species has a relatively high fitness cost.

Studying hominin pelves at the University of the Witwatersrand, South Africa

"Human childbirth therefore remains fundamentally associated with mortality and morbidity, which raises the question of how a process that is imperative for survival and reproduction could be so risky, and which selective pressures are ultimately responsible for maintaining such a precarious birth process." Haeusler et al., 2021

Below are a selection of my research projects :

  • Empirically tested the relationship between pelvic breadth and thermoregulation. One explanation for why the birth canal may not be larger is that, in line with ecogeographic rules, selection for effective thermoregulation in hot climates has constrained the size of the pelvis. I found, in a sample of 30 mixed sex runners who ran in a variety of climatic conditions, that pelvic breadth is significantly associated with core body temperature.

  • Studied a feature on the fossilized pubic bones of two presumed adult females from the genera Australopithecus sediba and Australopithecus afarensis. My co-authors and I compared the feature, which we term the "ventral sulcus", to pubic bones in a wide sample of primates, humans, and other hominins in an attempt to determine its etiology.

  • Created over 100 three-dimensional scans of modern human pelves from global osteological collections in order to test the relationships between dimensions of the pelvis. The purpose of this study is to clarify whether maximum pelvic breadth (bi-iliac breadth) covaries with birth canal dimensions.

  • Participated in a team that identified and analyzed a previously misclassified hominin first rib from Sterkfontein.

  • Contributed to a special issue of Paleoanthropology by studying the first rib, manubrium, and clavicle of Australopithecus sediba.

  • Studied clavicle shape and biacromial width and their relation to locomotion in hominins, humans, and apes.

  • Reconstructed the pelvis of Sts 14 (Australopithecus africanus) using 3D techniques in order to compare it to previous reconstructions.

  • Studied pubic symphyseal fusion and categorized epiphyseal maturation in apes in comparison to humans.

  • Participated in fieldwork in Kenya excavating 1.5 million year old hominin footprints, and in Tanzania searching for fossils at Laetoli.

Searching for hominin fossils at Laetoli in Tanzania

Chimpanzee pubic symphyses

Diagram of a female birth canal indicating the three major birth canal planes

Hard at work cataloguing Laetoli finds at the National Museum of Tanzania in Dar es Salaam