Pterosaurs, commonly but inaccurately referred to as pterodactyls, were diverse flying reptiles that dominated the skies during the Mesozoic Era (228 to 66 million years ago). They were the first vertebrates to achieve powered flight, independent of birds and bats. Though not dinosaurs, they lived alongside them, and their diet provides insight into their ecological roles.
Main Food Sources
Pterosaurs primarily consumed a carnivorous diet, with food sources often linked to their habitats. Many coastal species were piscivores, eating fish, squid, and shellfish. They used sharp beaks to snatch prey from the water; for example, Rhamphorhynchus is considered a fish-eater, supported by fossilized fish remains in its stomach. Beyond aquatic prey, smaller pterosaur species in forests or inland regions had more varied diets. These fliers often consumed insects and small vertebrates like lizards and eggs. This adaptability allowed pterosaur groups to occupy various ecological niches.
Dietary Specializations Across Species
Pterosaur diets varied considerably among species, reflecting diverse feeding strategies, evident in their unique anatomical features like beak shapes and tooth structures. Pterodaustro, for example, developed hundreds of fine, needle-like teeth, forming a sieve for filter-feeding small organisms like crustaceans and plankton from water or mud, similar to flamingos. Azhdarchids, a group including Quetzalcoatlus, are thought to have hunted small dinosaurs, carrion, and other ground animals. Their long hindlimbs suggest adaptation for walking and launching from land to search for food. Conversely, Istiodactylidae possessed recurved teeth suited for eating meat, indicating a predatory lifestyle. Some pterosaurs were generalists, consuming a wide array of invertebrates and vertebrates, such as Pterodactylus. Even within a single species, diet could change with age; juvenile Rhamphorhynchus likely ate insects, while adults transitioned to a fish-based diet. This indicates a flexible approach to foraging, exploiting available resources.
Paleontological Clues to Diet
Scientists uncover the diets of extinct pterosaurs through various types of fossil evidence. Direct evidence includes preserved stomach contents and coprolites (fossilized droppings). For instance, fossilized stomach contents revealed Dorygnathus ate small fish, while Campylognathoides consumed squid. Another approach involves analyzing tooth wear patterns, a technique called dental microwear analysis. This method examines microscopic scratches and chips on tooth surfaces, created by food consumption. By comparing these patterns to modern animals with known diets, paleontologists infer what pterosaurs ate; rougher wear suggests crunchy invertebrates, while smoother surfaces indicate softer foods like fish. Pterosaur skull, beak, and tooth morphology also provides clues. The shape of their jaws and the presence or absence of teeth, along with their structure (e.g., sharp, conical, or bristle-like), offer insights into feeding mechanisms. Elongated jaws with slender teeth point to agile prey capture, while robust jaws suggest consumption of tougher items. This combination of direct and indirect evidence allows scientists to reconstruct the diverse dietary habits of these ancient flying reptiles.