Smallest dinosaur of all time A hummingbird-sized dinosaur identified from a skull 1_____ in amber may be the smallest dinosaur from the Mesozoic Era ever found, according to a paper newly published in 2____ scientific journal Nature. Scientists 3______ the tiny, exceptionally well-preserved birdlike skull found in amber excavated from northern Myanmar's Hukawng Valley in 4_______. Radioisotope dating of zircon crystals in the 5_____ from this site suggests it was roughly 6_____ million years old. The skull is only 7.1 7______ long, indicating the dinosaur was similar 8_____ size to the bee hummingbird – the 9_____10_____ bird.