Earth

What did pterosaurs eat? New fossil study reveals their diet

A flying reptile with long membranous wings, a large yellow beak with spiky teeth, and a long tail.
Artist’s concept of the pterosaur Dorygnathus banthensis. Scientists know little about the diets of pterosaurs, but a new study reveals this species fed on small fish. Image via Dmitry Bogdanov/ Wikimedia Commons (CC BY-SA 3.0).
  • Scientists uncovered the diets of two pterosaur species found in Germany from fossilized stomach contents.
  • Dorygnathus banthensis mainly ate small fish, while Campylognathoides zitteli consumed squid, showing they had different diets.
  • The fossilized stomach contents offer valuable information about the feeding habits and ecosystems of pterosaurs in the Jurassic period.

What did pterosaurs eat?

Pterosaurs were winged reptiles that dominated the skies during the age of the dinosaurs. Historically, scientists knew little about the diet and feeding strategies of these creatures. On October 23, 2024, a group of researchers said they’ve examined two pterosaur specimens in great detail. Remarkably, they were able to find fossilized stomach contents. Moreover, they were even able to identify the prey consumed by the pterosaurs.

The scientists published their findings in the peer-reviewed Journal of Vertebrate Paleontology on October 23, 2024.

A look at pterosaur fossil number one

The researchers conducted a detailed study of two previously collected fossilized pterosaur species. The 182-million-year-old specimens came from a shale formation at Baden-Württemberg in southwest Germany.

They found one of the fossilized remains – belonging to the species Dorygnathus banthensis – had eaten small fish (from the genus Leptolepis) shortly before it died. Consequently, there was little time for the stomach acids to break down the fish bones. Thus, the bones of the food were also preserved in the fossil.

Top: A cluster of fossil bones in gray rock. Bottom: a colorful diagram labeling the bones.
The top panel shows the pterosaur fossil Dorygnathus banthensis. At the bottom is a diagram describing the bones, with a scale bar representing 0.8 inches (20 mm). The shaded gray area in the diagram with the arrow shows the location of the stomach where fish bones were. Image via Cooper, L.A.S., et al./ Journal of Vertebrate Paleontology/ (CC BY-NC-ND 4.0).

Pterosaur fossil number two

The other pterosaur species they examined was Campylognathoides zitteli. In this case, the stomach contents examination revealed the animal had consumed squid shortly before its death. The scientists knew it was squid because tiny hooks, attached to tentacles to grab prey, survived in fossilized form. Furthermore, based on the hooks, they could identify the squid species: Clarkeiteuthis conocauda. Thus, this discovery suggests that Campylognathoides may have been a nocturnal hunter, because squid travel to the sea surface at night.

Left: gray slab of shale with cluster of fossil bones. Right: colorful diagram identifying the bones.
The left panel shows the pterosaur fossil Campylognathoides zitteli with an accompanying diagram describing the bones. A scale bar at the bottom of the left panel shows 2 inches (51 mm). The shaded gray area in the diagram with an arrow indicates the location of the stomach where scientists found squid hooks. Image via Cooper, L.A.S., et al./ Journal of Vertebrate Paleontology/ (CC BY-NC-ND 4.0).

Fossilized stomach contents are extremely rare

These pterosaurs, like modern-day seabirds, spent much of their time flying in search of prey. They once soared over the warm tropical seas that covered south Germany during the Jurassic Period. In order to stay aloft for long periods, they had to digest their food quickly to reduce the weight in their stomaches. Therefore, it’s rare to find fossilized stomach contents in pterosaurs.

David Martill, from the University of Portsmouth, a co-author of the paper, said:

It is incredibly rare to find 180-million-year-old pterosaurs preserved with their stomach contents, and provides “smoking gun” evidence for pterosaur diets. The discovery offers a unique and fascinating glimpse into how these ancient creatures lived, what they ate, and the ecosystems they thrived in millions of years ago.

What these results tell us about the pterosaurs’ world

The scientists discovered two different pterosaur species, which existed at the same time, but appear to have had different diets. Samuel Cooper of the State Museum of Natural History Stuttgart, the lead author of the paper, said:

The fossilized stomach contents tell us a lot about the ecosystem at that time and how the animals interacted with each other. For me, this evidence of squid remains in the stomach of Campylognathoides is therefore particularly exciting. Until now, we tended to assume that it fed on fish, similar to Dorygnathus, in which we found small fish bones as stomach contents. The fact that these two pterosaur species ate different prey shows that they were likely specialized for different diets. This allowed Dorygnathus and Campylognathoides to coexist in the same habitat without much competition for food between the two species.

The pterosaurs were found in a unique fossil site

The geologic formation that held the fossilized remains of the two pterosaurs provides more insight into their aquatic world. It’s called the Posidonia Shale. This is a black shale formation, dated at 182 million years old. A part of this formation, where scientists found the two pterosaurs, lies in southwest Germany.

This region was once a muddy seabed. There, animals quickly sank into the soft mud before scavengers could get to them or sea currents could disturb their remains. And low oxygen levels kept the remains in good condition for fossilization.

The site is notable for its diverse and well-preserved fossilized marine fauna. Scientists have found remarkable specimens there, including a pregnant ichthyosaur with fossilized embryos, plesiosaurs, marine crocodiles, several large fish species, crustaceans, cuttlefish, ammonites and more pterosaurs.

Bottom line: Fossilized stomach contents of two well-preserved pterosaur species from southwestern Germany offered valuable information about the feeding habits and ecosystems of pterosaurs in the Jurassic period.

Source: Dietary tendencies of the Early Jurassic pterosaurs Campylognathoides Strand, 1928, and Dorygnathus Wagner, 1860, with additional evidence for teuthophagy in Pterosauria

Via State Museum of Natural History Stuttgart, Germany

Read more: New pterosaur species found in Queensland, Australia

Posted 
October 30, 2024
 in 
Earth

Like what you read?
Subscribe and receive daily news delivered to your inbox.

Your email address will only be used for EarthSky content. Privacy Policy
Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.

More from 

Shireen Gonzaga

View All