Shark Skeletons: Cartilage Not Bone
- A global team of scientists has mapped the intricate internal structure of shark cartilage, revealing how these ocean predators maintain both strength and flexibility.
- The study,a collaboration between Florida Atlantic University (FAU),the German Electron Synchrotron (DESY),and NOAA Fisheries,examined the cartilage of blacktip sharks (Carcharhinus Limbatus).These sharks, known for the black markings on...
- Using synchrotron X-ray nanotomography, researchers discovered that shark cartilage isn't uniform but consists of two distinct regions: the outer mineralized corpus calcareum and the inner intermediale.
Shark Cartilage Study Reveals Secrets to Strength and Flexibility
Updated june 02, 2025
A global team of scientists has mapped the intricate internal structure of shark cartilage, revealing how these ocean predators maintain both strength and flexibility. The research, focusing on blacktip sharks, offers insights that could lead to the development of advanced materials.
The study,a collaboration between Florida Atlantic University (FAU),the German Electron Synchrotron (DESY),and NOAA Fisheries,examined the cartilage of blacktip sharks (Carcharhinus Limbatus).These sharks, known for the black markings on their fins, inhabit warm, shallow waters worldwide.
Using synchrotron X-ray nanotomography, researchers discovered that shark cartilage isn’t uniform but consists of two distinct regions: the outer mineralized corpus calcareum and the inner intermediale. Both are composed of collagen and bioapatite, but their physical structures differ. The cartilage is porous and reinforced with struts, enabling it to absorb pressure from multiple directions.
This structure allows the cartilage to act like a spring, storing and releasing energy as the shark swims. The presence of bioapatite crystals aligned with collagen strands further enhances the material’s resistance to damage.Helical fiber structures prevent cracks from spreading,showcasing nature’s complex engineering.
Vivian Merk, assistant professor at FAU, said the shark’s mineral-reinforced spines work like springs, flexing and storing energy as they swim. Merk hopes that understanding how sharks achieve this can inspire new materials that are both strong and flexible, ideal for medical implants, protective gear, or aerospace design.
Nature builds remarkably strong materials by combining minerals with biological polymers, such as collagen – a process known as biomineralization. Sharks are a striking example. Their mineral-reinforced spines work like springs, flexing and storing energy as they swim.
When researchers applied pressure to microscopic pieces of shark vertebrae, they observed only slight deformations initially.fractures occurred only after repeated pressure, and even then, the damage remained confined, demonstrating the material’s resistance to failure.
After hundreds of millions of years of evolution,we can now finally see how shark cartilage works at the nanoscale – and learn from them. We’re discovering how tiny mineral structures and collagen fibers come together to create a material that’s both strong and flexible, perfectly adapted for a shark’s powerful swimming. These insights could help us design better materials by following nature’s blueprint.
Stella Batalama, dean of FAU’s College of Engineering and Computer Science, emphasized the power of interdisciplinary collaboration in uncovering nature’s secrets for building strong and flexible materials. The layered, fiber-reinforced structure of shark cartilage offers a compelling model for high-performance, resilient design, promising advancements in medical implants and impact-resistant gear.
What’s next
Future research will focus on mimicking the unique structure of shark cartilage to create new composite materials with enhanced strength, flexibility, and resilience for a wide range of applications.