Troodontids have sickle-claws and raptorial hands, and some of the highest non-avian encephalization quotients, meaning they were behaviourally advanced and had keen senses.

Although DNHM D2154 exhibits several juvenile-like features including free cervical ribs, unfused frontals and nasals, and a short snouted skull, other attributes, full fusion of all neurocentral synostoses and the sacrum, and dense exteriors to cortical bone, suggest a small, mature individual.

Microscopic examination of tibia and fibula histology confirms maturity and suggests an individual greater than two years old with slowed growth.

At this time, the Liaoning area was dominated by numerous volcanoes in a landscape that was covered in coniferous forest, with an understory of ferns and other plants like large horsetails.

[citation needed] There were many species of small birdlike theropod dinosaurs living in the area, although most of them were slightly larger than Mei.

Often, volcanoes erupted, entombing animals in ash and suffocating others with carbon monoxide, which accounts for the high level of preservation of fossils.