The human body is a marvel of engineering, but it’s a machine that requires maintenance and repair. At times, that means trying to replace parts lost to injury or illness. The oldest known prosthesis is the “Cairo toe,” crafted out of wood and leather and thought to be 2,700 to 3,000 years old. Its flexibility as well as signs that it was repaired multiple times suggest that it wasn’t built just for appearance — it helped the person walk.
Many efforts to improve replacement body parts followed, including a leg made from bronze and hollowed wood created in what’s now Italy around 300 B.C. Some people in Switzerland and Germany in the fifth to eighth centuries sported wood, iron or bronze feet. In the 15th century, cranks, gears and springs made artificial limbs more functional for those who had at least one hand to manage the hardware. The technology has improved exponentially since then, but one key challenge remains: making the replacement limb easy for the user to control. To solve that major problem, researchers are flipping the script and re-engineering the human body.
In this issue, we explore efforts to restore senses such as proprioception, a person’s sense of where their body is in space, after an amputation (SN: 10/3/24). Such efforts involve engineers who design prostheses in collaboration with surgeons. The surgeons reroute muscles affected by amputation, realigning them so they generate electrical signals more typical of uninjured musculature. Those signals then direct joints in the prosthesis. In a recent study, people with these new muscle-to-prosthesis interfaces increased their top walking speed by 40 percent. Other engineer-surgeon collaborations have rerouted nerves in order to send stronger signals to a prosthesis, or have connected an artificial limb directly to bone to avoid the too-common issue of pain caused by a prosthetic socket. In a paper, one of the scientists termed it “co-engineering the body and machine.”
We also delve into a very different form of research: fieldwork. Charles Darwin became famous for developing his theory of evolution by painstakingly gathering specimens of plants, animals and fossils around the world. Most field researchers never become household names, but their work matters.
I didn’t know about Margaret S. Collins, who became a global expert on termites, until our life sciences writer Susan Milius proposed a profile of Collins as part of our Unsung Characters series (SN: 11/27/24). And what a life she led. As a Black woman born in West Virginia in 1922, she was a contemporary of the Hidden Figures mathematician Katherine Johnson, and like her peer, Collins contended with both racism and sexism, which impeded her efforts to participate equally in the sciences and in society. Nevertheless, Collins persisted, becoming the first Black female entomologist Ph.D. in the United States, raising two sons and conducting field research in the United States, Central and South America, and the Caribbean.
Collins made fundamental observations about how termites adapt to hostile dry environments and provided a wealth of data for evolutionists investigating how related species become so diverse. The “termite lady” also opened the door for other women who dreamed of a life as a scientist in the field.