Palaeontologists have turned to robotics in an unusual attempt to recreate ancient life. The aptly named “palaeo-robots” could help scientists reconstruct how fish evolved to walk.
Four-legged land animals such as frogs, humans and dinosaurs all evolved from a marine ancestor. The fossil record shows that this transition from water to land occurred about 390 million years ago.
But exactly how these animals went from swimming to walking remains an open question in evolutionary biology.
“Since fossil evidence is limited, we have an incomplete picture of how ancient life made the transition to land,” says lead author Michael Ishida from Cambridge’s Department of Engineering and the Bio-Inspired Robotics Laboratory.
Crucially, water and land environments have different physical requirements for movement. For example, land animals cannot rely on water’s buoyancy and must have joints that support their weight as they walk.
“Palaeontologists examine ancient fossils for clues about the structure of hip and pelvic joints, but there are limits to what we can learn from fossils alone,” says Ishida. “That’s where robots can come in, helping us fill gaps in the research, particularly when studying major shifts in how vertebrates moved.”
The team is creating robotic analogues of ancient fish skeletons, complete with mechanical joints that mimic muscles and ligaments. This allows palaeontologists to take an experimental approach to testing hypotheses about ancient movement.
“We want to know things like how much energy different walking patterns would have required, or which movements were most efficient,” says Ishida. “This data can help confirm or challenge existing theories about how these early animals evolved.”
Because the fossil record is incomplete, with many species only known from partial skeletons, palaeo-robotics requires some educated filling-in-the-gaps.
“In some cases, we’re just guessing how certain bones connected or functioned,” said Ishida. “That’s why robots are so useful—they help us confirm these guesses and provide new evidence to support or rebut them.”
“There are only a few groups doing this kind of work,” says Ishida. “But we think it’s a natural fit – robots can provide insights into ancient animals that we simply can’t get from fossils or modern species alone.”
The team’s approach to designing and building palaeo-robots is published in the journal Science Robotics.
