Unveiling the Sky Sovereigns: The Rise of Ancient Flying Reptiles Through Groundbreaking Research

Researchers have been intrigued by how pterosaurs became the initial vertebrates to conquer flight. Certain pterosaur species, like the Quetzalcoatlus, were the largest known creatures to ever soar through the skies, boasting wingspans exceeding ten meters (comparable to military aircraft such as the Spitfire). The recent study conducted by my team might contribute to solving this evolutionary enigma, demonstrating how a vane located at the tip of their tails could have facilitated more efficient flying in these ancient beings.

It required a considerable duration for active flight to develop in nature. The earliest flying creatures were insect-like dragonflies, which flapped their wings above the swampy woodlands of the Carboniferous period (over 300 million years ago). Approximately 100 million years later (in the Triassic period), the first bony creatures, or vertebrates, took to the skies. These vertebrates were pterosaurs, which reigned over the skies in the Mesozoic era, a time spanning from 251 to 66 million years ago, gliding above dinosaurs.

Pterosaurs differed drastically from any known contemporary animal. Picture a flying squirrel crossed with a reptile. All recognized members of this animal classification perished 66 million years ago, leaving behind no living descendants.

Their wings consisted of a flexible membrane supported by an elongated fourth finger and were likely enveloped in a fur-like outer protective covering. One might think it’s challenging to determine the appearance of creatures existing hundreds of millions of years prior to human existence. Nevertheless, technology can assist us in virtually traveling back in time and adding flesh to the skeletons of long-extinct animals.

Our study employed a novel technology, Laser Stimulated Fluorescence (LSF), which enables us to observe fossilized tissues that are invisible to the naked eye. The laser activates various minerals and chemical traces present in the fossil, causing it to emit vibrant fluorescence and stand out against the gray rock surrounding it. It can unveil claws, beaks, skin, feathers, even intricate toepads of creatures like dinosaurs that would otherwise remain unseen. The resulting image resembles a photograph of Jurassic roadkill.

Our group of palaeontologists from the University of Edinburgh and the Chinese University of Hong Kong gathered pterosaur fossils preserved in museums (such as the Natural History Museum in London or the National Museum of Scotland in Edinburgh) and captured images of them in darkrooms, making the most of the lengthy exposure under the laser.

To our astonishment, intricate images of tail membranes emerged in several specimens, along with a grid of supportive structures previously unobserved. The pterosaurs we analyzed belonged to the same species, Rhamphorhynchus. Rhamphorhynchus was a moderately sized pterosaur, comparable, if not slightly smaller than a contemporary albatross. It possessed a slender beaked jaw filled with needle-like interlocking teeth, ideal for squid-catching. It glided above the lagoons of Central Europe during the Jurassic period nearly 150 million years ago.

Jurassic revelations

Birds flapped into existence sometime during the Jurassic, tens of millions of years after the first pterosaurs (around 130 million years ago). Bats were the last to join the flying phenomenon. These flying mammals emerged following the extinction of the dinosaurs, appearing in the Eocene epoch, 50 million years ago.

Most soaring vertebrates evolved shorter bony tails as they ascended into the skies. Early pterosaurs were distinct from other flying creatures due to their long, slender bony tails featuring a paddle-like “vane” that varied in shape depending on the species and age of the animal. For instance, in the juvenile pterosaur Rhamphorhynchus, baby specimens displayed teardrop-shaped tail vanes. During their adolescent phase, the vane adopted a kite-like contour, and in adulthood, it resembled a triangular heart.

The specimens examined in our research exhibited a kite-shaped tail vane filled with intersecting structures, akin to ribs and spars found in an aircraft wing. This internal lattice might have permitted the membrane to dynamically tighten, similar to a sail on a boat, and minimize flutter that could hinder flight performance.

As pterosaurs advanced and grew lighter and larger, their tails reduced in size, eventually vanishing altogether.

Gaining insight into the tail’s function could enhance our understanding of the development of flight, which could, in turn, inspire future advancements, such as aircraft, drones, and even tent designs. We can also uncover details about the behaviors and appearances of animals we can never observe alive.

Pterosaurs paved the way for flight, now lost in a mass extinction. It is plausible that pterosaurs possessed numerous flight-enhancing adaptations that remain undetected in the fossil record. However, with advancing technologies like the LSF, we may uncover more insights into their aerial accomplishments and appearance. We can now envision how this extinct being may have looked, lived, and functioned—an even safer version of the Jurassic Park films.