A team of scientists may have finally solved the mystery of how plesiosaurs—ancient marine reptiles with four large flippers—moved through prehistoric oceans.
This breakthrough, published in Scientific Reports, reveals a new way of thinking about plesiosaur swimming based on motion control rather than just water flow around their bodies.
Plesiosaurs, which lived millions of years ago, had unique bodies with four equally-sized flippers.
For years, scientists have puzzled over how they used these flippers to swim. Unlike modern sea animals, plesiosaurs’ swimming technique didn’t match any existing species, making it hard to understand their movement.
Researchers from Tohoku University, Kanagawa University, and the University of Manchester joined forces to tackle this “four-wing problem.”
Instead of only studying water movement around plesiosaurs, they developed a bio-inspired control system that considers how these creatures may have coordinated their limbs to swim in various conditions.
Professor Akio Ishiguro from Tohoku University explains, “We looked at how plesiosaurs might control their movement patterns to swim at different speeds and adapt to different situations.”
To recreate this, the team designed a robot model of a plesiosaur and programmed it with an autonomous, decentralized control system inspired by limb coordination in modern four-legged animals like dogs and cats.
This model allowed them to explore how the fore and hind flippers might work together for smooth, flexible movement.
The team’s experiments revealed that their control system helped the robot mimic coordinated, adaptable swimming patterns, showing how plesiosaurs could have adjusted their movements based on the flapping cycle and body shape.
Lead researcher Akira Fukuhara explains, “Our approach helps us understand how extinct animals like plesiosaurs could adapt their movement patterns to different situations. This opens up the possibility of studying other ancient creatures and their unique ways of moving.”
The researchers now hope to take their findings further by building models that include other parts of plesiosaur bodies, such as their famously long necks, which varied greatly in length.
By factoring in these elements, they aim to get an even clearer picture of how these fascinating marine reptiles moved.
This study offers a new glimpse into the underwater life of plesiosaurs and sheds light on the complex movement abilities of other extinct species, bringing us closer to understanding how ancient animals adapted to their environments.
Source: Tohoku University.
