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In 1668, a Dutch doctor named Jacob van Meekeren had a daring plan. A patient had recently come into his care with a unique injury—a badly deformed skull. He was a soldier who had seen the brutalities of war, and while he lived to tell the tale, he was severely injured on the battlefield. Van Meekeren proposed a surgical fix: placing a fragment of another skull in the injured space to right its shape. You might wonder where one gets a piece of a skull without committing some color of crime, and so did van Meekeren.
Using a human skull was going to be tricky, so he decided that the best solution here was to use a fragment of a dog’s skull (I’m guessing van Meekeren was a cat person). So, he cut open the soldier’s head and situated the dog skull fragment into the place of the injury. The surgery was a success, and the soldier went on to live an ... unhappy life. An issue arose that van Meekeren hadn’t foreseen. The patient’s church decided that he was now partially dog and could no longer be a member of the parish. The church excommunicated him, and he was devastated to lose his community.
In desperation, the soldier returned to van Meekeren and pleaded for him to remove the dog skull. He obliged, though was surely disappointed at ruining his successful surgery. But when van Meekeren opened up the soldier’s head for the second time, he saw something amazing. The fragment of the dog skull was completely fused into the soldier’s skull and irremovable. He had performed the first successful bone graft in recorded history.
It took the fresh eyes of a medical student to recognize how much coral resembled human bone.
Bone grafts have come a long way since the 1600s, and the materials used today don’t get people excommunicated from their churches. But bone graft surgeries have still had their share of issues. Bones are a unique kind of tissue because they are a mixture of crystalized minerals attached to proteins. The minerals are held together in an orderly fashion with the help of a matrix of collagen. Bones need to be strong enough to withstand the forces that we put on them with our bodies, but they also need to be light enough to allow mobility.
This is a tricky balance, so to accomplish this feat, bones have several different layers. The outer shell, the hard white part you think of when you think of a skeleton, is strong and dense. The inside, however, is hollow and filled with spongey, porous tissue that contains blood vessels. Bones are living tissue that is constantly remodeling, so if a fracture is small, it will heal on its own. If there is a gaping space, however, the bone is going to struggle to repair itself. The best way to deal with this is to provide a scaffold in the way of a bone graft. By providing an appropriate structure, the bone can continue to remodel, fusing the graft with new bone growth.
As van Meekeren saw, finding the bone for a graft can be tricky. An organ donor can be used, but that requires a dead body and introduces a small possibility of disease transmission. Another method is to use a piece of bone from the patient’s own body. This requires two surgeries—one to remove a piece of bone from another part of the patient’s body and a second to place that bone into the area of concern. Two surgeries, of course, are more than one surgery, and this method increases the risk of complications.
For years, doctors searched for an effective substitution but struggled to find a material that would work. Experiments were run with synthetic materials such as wood and marble without luck. The first foreign material that offered a glimmer of hope was plaster of Paris. The biggest issue was creating an artificial structure with a matrix to let blood vessels grow throughout the remodeled bone. This has proved to be a difficult task. Engineers tried to create scaffolding with porous ceramics, but it just didn’t have the uniform matrix of natural bone. So doctors were stuck with using cadavers or performing two surgeries.
Bone grafts have come a long way since the 1600s, and the materials used today don’t get people excommunicated.
Bone grafts were nowhere near Jon Weber’s mind as he studied coral reefs. He was a marine geologist at Penn State University, and he was far more interested in learning about the chemical composition of corals than the shortcomings of the medical community. Weber was particularly interested in learning how the chemicals found in the coral skeletons varied by species and environment, and he published many papers on his findings through the 1960s and 1970s.
When Penn State got some fancy new technology, however, Weber’s research would completely change. Penn State became one of the first research institutions in the United States to get a scanning electron microscope, which, unlike traditional microscopes, allows a three-dimensional view of a sample. Eugene White was a material scientist at Penn State University, and he had the honor and responsibility of running this highly coveted piece of technology. Weber was curious to look at a coral skeleton, so he asked White if he could use the scanning electron microscope. As a scuba diver himself, White was also intrigued.
People from all over the country had brought materials for White to analyze, but this was the first time he had a personal interest in the material. They performed the scans, and what they saw completely blew them away. The skeletons had a network of interconnected holes throughout—like Swiss cheese, but with way too many holes. Even with White’s vast experience, the coral looked like nothing else he had ever seen. It certainly looked nothing like any human-made material he had seen.
It took the fresh eyes of a medical student to recognize how much it resembled human bone. In 1971, White invited his nephew Rodney, who was a student at the State University of New York Upstate Medical University, to spend the summer working in his lab. The three studied the structure of corals and took molds. It became clearer that nature had created the perfect matrix for a bone graft that engineers had failed to replicate. Since the pores of the coral skeleton were uniform in size and completely interconnected, it was the ideal scaffold for new blood vessels and tissues to grow onto the graft. Excited about their new idea, they published a paper in 1972 that suggested coral as a good source of graft material.
This was all very exciting to the medical community, but there was one glaring problem. Coral skeletons are made of calcium carbonate, and calcium carbonate dissolves—it’s a common treatment for an overly acidic stomach! The material would break down in the body before bone could begin to grow. They needed a way to change the chemical composition of the coral without affecting how the coral skeleton grew.
This is when chemist Della Roy became involved in the project. Like a magician, Roy placed the coral into a phosphate solution and then heated it under high pressure. This converted the calcium carbonate to calcium phosphate, the same mineral as human bone, without changing the structure. The new material was named coralline hydroxyapatite, and it was welcomed into the medical community. Not only did it make a fantastic scaffolding for bone growth, but there were very few negative reactions in animal and human studies. Today this material has been used in the bone grafts of tens of thousands of patients, for everything from dental implants to spinal fusion.
What began as a desperate solution involving a dog skull in 1668 has evolved into one of the most innovative uses of marine life in modern medicine. Nature had already built the perfect scaffold; it just took a few curious minds, from scuba divers to surgeons, to recognize it. 
Excerpted from The Salmon Cannon and the Levitating Frog: And Other Serious Discoveries of Silly Science. Copyright © 2025 by Carly Anne York. Available from Basic Books, an imprint of Hachette Book Group, Inc.
Lead image: Vsevolod FINCH Ziablov / Shutterstock
