Around 71 million years ago, a tiny theropod dinosaur nestled up to nap one last time before entering the fossil record. This particular specimen was discovered in the Barun Goyot Formation within the Gobi Desert of Mongolia, revealing fascinating insights into their behavior that indicate a similar sleeping posture to modern birds.
The fossil, a near-complete 3D preserved specimen, belongs to a previously unknown species called Jaculinykus yaruui. Derived from the Greek word “Jaculus” for a small dragon and “onykus” for claw, this name emphasizes the creature’s quick and agile nature.
This tiny, rapid dinosaur offers an intriguing glimpse into the prehistoric past. While it was initially assumed to be an early flightless bird, it is now classified as a non-avian Maniraptoran dinosaur, closely related to birds.
The curled up snoozy Jaculinykus yaruui fossil.
The rest position of J. yaruui offers significant parallels to certain avian species, providing invaluable evidence of their avian-like behavior long before flying birds appeared. They exhibited traits commonly found in birds, reflecting a possible connection between the two groups.
It’s speculated that the unique wrist structure allowed them to snatch items, possibly contributing to the evolution of flight. However, one consistent feature is their sleeping posture, resembling modern birds, hinting at shared behaviors and potential adaptation for warmth.
The findings have been detailed in the journal PLoS ONE.
