Writing in the journal Bioinspiration & Biomimetics, engineer and biomimetics expert Stuart Burgess examines “Design features in human joints with recommendations for humanoid robot design.” This paper argues more forcefully than his previous peer-reviewed publications that the extraordinary design of human anatomy cannot be adequately explained by evolution and instead points to intelligent design. He refers to the term explicitly. The acceptance of this paper serves as a harbinger of a broader design revolution beginning to take root in biology.
Biology Surpassing Human Engineering
Burgess describes the different types of movable joints in humans, and he explains why the “human musculoskeletal system has a level of design sophistication far higher than the best current humanoid robots.” In addition, he recommends how biological design could be applied in human robotics. He summarizes as follows:
The paper describes 14 different types of moveable joint in the human musculoskeletal system and describes important design features such as linkage mechanisms, suspension systems and segmentation. In each case, recent examples of bioinspired design or potential for bioinspired design are given…. Human joints exhibit design principles that are quite different to those of traditional engineering such as high degrees of freedom, redundant actuation and multisensory integration. These strategies have potential to inspire a different and more effective approach to the mechanical design of humanoid robots.
This study represents the culmination of his biomimetics research in human anatomy, which I have covered extensively (here, here, here). Burgess has not only demonstrated the exquisite engineering of human anatomy, but he has also discredited arguments for life displaying sloppy design (here, here, here).
Engineering of Human Joints
Burgess identified several features of human joints that enhance their performance:
- Diverse architectures: fixed-center hinge, linkage hinge with moving center, suspended hinge, shaft-sleeve pivot, etc.
- Multiple degrees of freedom enabled by “sophisticated design features such as linkage mechanisms, suspension systems and segmentation.”
- Multifunctionality that allows “reducing the number of interfaces, increasing compactness and lowering weight.”
- Redundancy that enables “a wide range of muscle activation patterns to be produced for the same movement,” which provides “robustness because if a muscle is injured or tired or misaligned, other muscle patterns can be adopted to make movements.”
- Tailored linkage mechanisms that allow “fine-tuning design goals such as speed amplification, force amplification as well as motion paths.”
These features explain why human limbs perform far better at diverse tasks than even the most advanced robots:
The human musculoskeletal system has a level of design sophistication far higher than the best current humanoid robots. A recent research paper on finger biomechanics states the following: “In the orchestra of human movement, the fingers of the hand perform a symphony of astonishing complexity, orchestrated by a biomechanical engineering of precision.” One textbook on kinesiology states that the structures of the foot “work in perfect synchronization.”
Superiority of design is also displayed in other mammals:
Of course, robots can be highly efficient and superior to animals in some well-defined tasks. However, for dynamic movements, mammals are often far superior in terms of speed, agility and range, especially in unstructured environments. Key examples of agility include: catching, climbing, sprinting, leaping, and being able to quickly change running direction. Such actions require fast, precise and coordinated movements of multiple joints.
Design versus Evolution
Burgess did not pull any punches in his discussion. He bluntly states that the exquisite design of animal limbs is not expected within an evolutionary framework:
The extreme levels of sophistication in hands and feet is surprising given that evolutionary changes are assumed to be highly constrained to small step changes from one generation to the next. Steven Vogel has explained this apparent contradiction this way: “The dazzling diversity of the living world too easily disguises the fact that the evolutionary process faces constraints far more severe than anything impeding human designers.” Some studies on complex biological systems point to non-incremental origin of design concepts. In a review of fish jaw linkage mechanisms, Wesneat stated that some of these mechanisms have the appearance of sudden “transitions in engineering design.” In a detailed review of mechanical linkage mechanisms in nature, Muller stated that it is very difficult to postulate how complex linkage mechanisms could evolve in small steps.
Even more, he cites several books arguing for biology demonstrating intelligent design:
In addition, some scientists have argued that intelligent design concepts such as goal-directed design are necessary to explain the complexity of biological systems [152-157].
References 155–157 are to books by three modern design proponents: Can Science Explain Everything? by John Lennox, Signature in the Cell by Stephen Meyer, and The Design Inference by William Dembski. The fact that a journal committed to scientific materialism published an article explicitly challenging evolution and promoting design by name reflects how the evidence for design has become so persuasive that even those opposing this conclusion feel obligated to acknowledge the strength of the argument.