Friday, October 23, 2015

Faculty Spotlight

Matthew O’Neill, PhD, has spent more than a decade studying the evolution and biomechanics of gait (walking).

Ultimately, O’Neill said he hopes the work he’s doing will not only uncover more insight into understanding the evolution of human walking, but provide physicians with information that could benefit their patients.

“The more information we can glean about how human walking works, that data can be applied to a clinical context where it can be used for things like: making better limb prostheses and developing treatments for individuals who have problems walking,” he said.

After completing his undergraduate degree, O’Neill recognized his passion for research and enrolled in the Center for Functional Anatomy and Evolution at the Johns Hopkins University School of Medicine in 2001.

“It was kind of a hybrid anatomy, functional morphology and evolutionary biology program,” he explained. “The students in that program do research that's evolutionary in nature and typically focused on interpreting fossils; in particular, reconstructing how fossil species walk, run and climb by combining studies of their skeletal remains with studies of how similar-looking anatomy works in living animals.”

Over the course of the next eight years, O’Neill refined his focus towards understanding the structural basis for the metabolic cost of locomotion (the subject of his PhD dissertation) — in other words, finding out what it is about the mechanics of walking that determines the amount of energy that is expended. What is going on in those limbs that drives that cost?

The cost of locomotion can be fascinating when looking at it from an evolutionary perspective because studies have shown improvement of locomotor efficiency to be favorable in natural selection. Indeed, humans are very efficient walkers, especially compared to our closest living relative, the chimpanzee. This has suggested to many researchers that much of human lower limb anatomy may have evolved in order to reduce our cost of walking.

After accepting a position as a post-doctoral researcher at Stony Brook University, O’Neill found a seemingly unquenchable thirst for more knowledge about the evolution of human walking capabilities and the question of how to accurately predict how the human body has changed over time and the reasons behind it.

Thus began the start of an ongoing project on the biomechanics of walking in humans and bipedal chimpanzees; research that has since followed him across the country to his current pursuits at the UA College of Medicine – Phoenix.

Researchers have collected a rich set of data comprising everything from how much force their limbs apply to the ground to how their limbs move and how individual muscles are activated during a walking stride. This comprehensive database has proved instrumental in their quest to gain insight into what the major differences are that underlie the mechanics of chimp-like walking as opposed to bipedal walking.

The project that O’Neill and the other researchers in the cohort started years ago has yielded publications of their work in scientific journals such as: the Journal of Human Evolution and Journal of Experimental Biology. Recent findings were published on Oct. 6th in the journal, Nature Communications; however, research remains ongoing.

“We’re trying to address a handful of questions about the evolution of human walking and trying to understand what the mechanical base is for some of the big differences we see between the way chimpanzees and humans walk,” O’Neill explained. “Our aim was to provide a different approach towards reconstructing the way these different early hominins were walking around their landscape and then use that information to get a better handle on what the selective pressures might have been that forced these evolutionary changes.”

Dr. O'Neill's research interests include:

  • The evolution of vertebrate morphology in non-human primates;
  • the biomechanics of bipedal walking;
  • and the platform development for medical devices and procedures.

Article by Evan Rosenfeld

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About the College

The University of Arizona College of Medicine – Phoenix admitted its inaugural class of first-year medical students in August 2007 and is celebrating its 10th anniversary this year. The college inspires and trains exemplary physicians, scientists and leaders to optimize health and health care in Arizona and beyond. It has graduated 354 physicians and has 328 students in training in its continuing mission to address the physician shortage in Arizona. The college is uniquely positioned to accelerate the biomedical and economic engines in Phoenix and the State by leveraging vital relationships with key clinical and community partners.