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Rahonavis is one of those creatures that triggers enduring feuds among paleontologists. When it was first discovered (an incomplete skeleton unearthed in Madagascar in 1995), researchers assumed it was a type of bird, but further study showed certain traits common to dromaeosaurs (better known to the general public as raptors). Like such undisputed raptors as Velociraptor and Deinonychus, Rahonavis had a single huge claw on each hind foot, as well as other raptor-like features.
What is the current thinking about Rahonavis? Most scientists agree that raptors counted among the early ancestors of birds, meaning that Rahonavis might be a "missing link" between these two families. The trouble is, it wouldn't be the only such missing link; dinosaurs may have made the evolutionary transition to flight multiple times, and only one of these lineages went on to spawn modern birds.