How Animal Joints Challenge Evolutionary Pathways
Dr. Stuart Burgess has been studying the arrangement, design, and shape of vertebrate limbs and joints for years. He shares what he learns with engineers working in the field of biomechanics. On this ID The Future, Dr. Burgess discusses his new paper on multi-functioning animal joints with host Dr. Brian Miller.
Joints have good examples of irreducible complexity, such as the knee joint’s four bar linkage or the arched structure of the foot. But animal joints are also multi-functional: designed to perform multiple different functions. This adds an extra layer of irreducible complexity that would require forward planning to accomplish. “Multi-functioning greatly narrows the solution space,” explains Burgess. “So if life has evolved by chance, you would not expect animals to have so much multi-functioning, and yet animals are full of these multi-functioning joints.”
Dr. Burgess also tackles the argument that some biological systems exhibit poor design. As an example, he discusses the ACL or anterior cruciate ligament. Burgess notes that we have more problems with our ACL today than we did a hundred years ago. Some claim the ACL is poorly designed, incapable of accommodating our active lifestyles in the modern age. Dr. Burgess critiques this argument, explaining why the ACL exhibits optimal design and pointing to misuse as the culprit for most ACL injuries, not the design of the joint.
Dig Deeper
- Read the paper that inspired this conversation: How Multifunctioning Joints Produce Highly Agile Limbs in Animals with Lessons for Robotics
- Learn more about Dr. Burgess’s research at his website.