Robert Bakker's illustration for John Ostrom's 1969 monograph,[15] showing the dromaeosaurid Deinonychus in a fast run, is among the most influential paleontological reconstructions in history.

[16] The dromaeosaurid body plan includes a relatively large skull, serrated teeth, narrow snout (an exception being the derived dromaeosaurines), and forward-facing eyes which indicate some degree of binocular vision.

As late as 2001, Mark Norell and colleagues analyzed a large survey of coelurosaur fossils and produced the tentative result that dromaeosaurids were most closely related to birds, with troodontids as a more distant outgroup.

[35] In 2002, Hwang and colleagues utilized the work of Norell et al., including new characters and better fossil evidence, to determine that birds (avialans) were better thought of as cousins to the dromaeosaurids and troodontids.

[38] In his own work, Gregory S. Paul pointed out numerous features of the dromaeosaurid skeleton that he interpreted as evidence that the entire group had evolved from flying, dinosaurian ancestors, perhaps an animal like Archaeopteryx.

The most basal known subfamily of dromaeosaurids is Halszkaraptorinae, a group of bizarre creatures with long fingers and necks, a large number of small teeth, and possible semiaquatic habits.

One possible member of this group, Rahonavis, is very small, with well-developed wings that show evidence of quill knobs (the attachment points for flight feathers) and it is very likely that it could fly.

Senter and colleagues expressly coined the name without the subfamily suffix -inae to avoid perceived issues with erecting a traditional family-group taxon, should the group be found to lie outside dromaeosauridae proper.

[53] Sereno offered a revised definition of the sub-group containing Microraptor to ensure that it would fall within Dromaeosauridae, and erected the subfamily Microraptorinae, attributing it to Senter et al., though this usage has only appeared on his online TaxonSearch database and has not been formally published.

[32] Rahonavis Buitreraptor Unenlagia Sinornithosaurus Microraptor Bambiraptor Tianyuraptor Adasaurus Tsaagan Saurornitholestes Velociraptor Deinonychus Atrociraptor Achillobator Utahraptor Dakotaraptor Dromaeosaurus Another cladogram constructed below follows the phylogenetic analysis conducted in 2017 by Cau et al. using the updated data from the Theropod Working Group in their description of Halszkaraptor.

When John Ostrom described it for Deinonychus in 1969, he interpreted the claw as a blade-like slashing weapon, much like the canines of some saber-toothed cats, used with powerful kicks to cut into prey.

However, Manning et al. argued that the claw instead served as a hook, reconstructing the keratinous sheath with an elliptical cross section, instead of the previously inferred inverted teardrop shape.

[69] In 2009 Phil Senter published a study on dromaeosaurid toes and showed that their range of motion was compatible with the excavation of tough insect nests.

This proposal is based primarily on comparisons between the morphology and proportions of the feet and legs of dromaeosaurids to several groups of extant birds of prey with known predatory behaviors.

Fowler found that the feet and legs of dromaeosaurids most closely resemble those of eagles and hawks, especially in terms of having an enlarged second claw and a similar range of grasping motion.

The arms, which could exert a lot of force but were likely covered in long feathers, may have been used as flapping stabilizers for balance while atop a struggling prey animal, along with the stiff counterbalancing tail.

With the addition of mathematical models and equations, Bishop simulated the conditions that would provide maximum force at the tip of the sickle claw and therefore the most likely function.

These results are consistent with the Fighting Dinosaurs specimen, which preserves a Velociraptor and Protoceratops locked in combat, with the former gripping onto the other with its claws in a non-extended leg posture.

[73] A 2020 study by Gianechini et al., also indicates that velociraptorines, dromaeosaurines and other eudromaeosaurs in Laurasia differed greatly in their locomotive and killing techniques from the unenlagiine dromaeosaurids of Gondwana.

These differences in locomotor and predatory specializations may have been a key feature that influenced the evolutionary pathways that shaped both groups of dromaeosaurs in the northern and southern hemispheres.

[76] However, not all paleontologists found the evidence conclusive, and a subsequent study published in 2007 by Roach and Brinkman suggests that the Deinonychus may have actually displayed a disorganized mobbing behavior.

Modern diapsids, including birds and crocodiles (the closest relatives of dromaeosaurids), display minimal long-term cooperative hunting (except the aplomado falcon and Harris's hawk); instead, they are usually solitary hunters, either joining forces time to time to increase hunting success (as crocodilians sometimes do), or are drawn to previously killed carcasses, where conflict often occurs between individuals of the same species.

[78] In 2001, multiple Utahraptor specimens ranging in age from fully grown adult to tiny three-foot-long baby were found at a site considered by some to be a quicksand predator trap.

Some consider this as evidence of family hunting behaviour; however, the full sandstone block is yet to be opened and researchers are unsure as to whether or not the animals died at the same time.

In addition to confirming the hypothesis that the sickle claw was held retracted off the ground, the trackway (made by a large, Achillobator-sized species) showed evidence of six individuals of about equal size moving together along a shoreline.

[25] Changyuraptor yangi is a close relative of Microraptor gui, also thought to be a glider or flyer based on the presence of four wings and similar limb proportions.

Due to its size and short arms it is unlikely that Zhenyuanlong was capable of powered flight (though the importance of biomechanical modelling in this regard is stressed[31]), but it may suggest a relatively close descendance from flying ancestors, or even some capacity for gliding or wing-assisted incline running.

In 2001, Bruce Rothschild and others published a study examining evidence for stress fractures and tendon avulsions in theropod dinosaurs and the implications for their behavior.

[87] At least one dromaeosaurid group, Halszkaraptorinae, whose members are halszkaraptorines, are most likely to have been specialised for aquatic or semiaquatic habits, having developed limb proportions, tooth morphology, and rib cage akin to those of diving birds.

[91] A study published in November 2018 by Norell, Yang and Wiemann et al., indicates that Deinonychus laid blue eggs, likely to camouflage them as well as creating open nests.