dromaeosaurids

Dromaeosaurids were a clade of small to medium-sized, feathered carnivorous theropod dinosaurs within the broader group of paravians, which also includes birds. They lived during the Jurassic and Cretaceous periods, roughly 160 to 66 million years ago, with fossils found on multiple continents including North America, Asia, and Europe.

The most distinctive feature of dromaeosaurids is the enlarged, sickle-shaped claw on the second toe, which could be raised off the ground and used to grasp or slash at prey. They had grasping hands, a lightweight, agile skeleton, and tails with stiffened segments for balance and maneuverability. Fossil impressions and specimens indicate they were covered in feathers, ranging from simple filamentous structures to more complex wing-like feathers on the arms and tail, underscoring their close relationship to birds.

Ecology and behavior interpretations suggest they were versatile carnivores that hunted a range of prey sizes, from small vertebrates to larger animals. Their limb proportions imply rapid, bipedal locomotion and proficient running ability. The idea that they hunted in coordinated groups is debated and not universally accepted, though some fossil associations have been cited in discussions of social behavior.

Relationship to birds: dromaeosaurids are among the closest non-avian relatives of birds, sharing features such as a furcula (wishbone), feathered bodies, and other skeletal traits. They illuminate aspects of the evolution of flight-related adaptations, even though none are considered direct ancestors of modern birds.

Notable genera include Velociraptor, Deinonychus, Dromaeosaurus, Utahraptor, and Microraptor, representing a range of sizes and morphologies within the group.