Tropical storms killed these baby flying reptiles 150 million years ago, study finds

A new study reveals the tropical conditions 150 million years ago in southern Germany were perfect to preserve two baby pterosaurs, named Lucky and Lucky II.

Tropical cyclones have been dangerous and deadly even since the time of giants, but paleontologists turned to some of the smallest reptile fossils to reveal the power of these storms. 

While the bigger reptiles in the late Jurassic era are the big bones that visitors flock to see at museums around the world, the little creatures are less talked about because the fossilization process was harder on the smaller critters, according to University of Leicester paleontologists behind a new study about two tiny reptiles. 

In the case of two baby pterosaurs, named Lucky and Lucky II, the conditions in the 150-million-year-old Solnhofen Limestones of southern Germany were perfect to preserve these tiny flying reptiles.

WHERE DINOSAUR BONES ARE REVEALED BY THE WEATHER

This region has produced more than 500 examples of pterosaurs over the last 250 years, nearly all small and well-preserved species, according to the study. This goes against the basic assumption that the larger reptiles would be better fossilized. 

"Pterosaurs had incredibly lightweight skeletons. Hollow, thin-walled bones are ideal for flight but terrible for fossilization," said study author Rab Smyth, with the University of Leicester’s Centre for Palaeobiology and Biosphere Evolution. "The odds of preserving one are already slim, and finding a fossil that tells you how the animal died is even rarer."

The study authors were able to use UV light to perform post-mortems, revealing the same injury to both Luckies. 

"Lucky’s left wing and Lucky II’s right wing were both broken in a way that suggests a powerful twisting force, likely the result of powerful gusts of wind rather than a collision with a hard surface," according to the university. 

The study authors say tropical storms helped preserve these creatures as they sank to the seafloor, creating poor conditions for scavenging and decomposition but creating the perfect environment for their delicate skeletal remains, and in some cases, soft tissues.

"Storm-generated mud rapidly buried these organisms, ensuring fossilization. As with most exceptionally preserved Solnhofen fossils, the specimens discussed here were recovered from the base of these storm deposits," according to the study.

Lucky I and Lucky II were likely only a few days or weeks old, but when their bodies were flung into the lagoon by powerful winds, it helped ensure they would be perfectly preserved for an estimated 150 million years. 

"For centuries, scientists believed that the Solnhofen lagoon ecosystems were dominated by small pterosaurs," Smyth said. "But we now know this view is deeply biased. Many of these pterosaurs weren’t native to the lagoon at all. Most are inexperienced juveniles that were likely living on nearby islands that were unfortunately caught up in powerful storms."