Timeline of troodontid research

Troodontid remains were among the first dinosaur fossils to be reported from North America after paleontologists began performing research on the continent, specifically the genus Troodon itself.

[2] Many milestones of troodontid research occurred between the description of Troodon and the resolution of their confusion with pachycephalosaurs.

[3] In the 1960s and 1970s researchers like Russell and Hopson observed that troodontids had very large brains for their body size.

[5] This decade also saw the first potential report of European troodontid remains, although this claim has been controversial.

[4] A single mysterious tooth from the Late Jurassic Morrison Formation of the United States was described as the oldest known troodontid remains, although this has also been controversial.

Artistic restoration of Byronosaurus with secretary bird -like plumage
The Troodon formosus holotype tooth
Paronychodon teeth
Holotype skull of Saurornithoides
Partial Stenonychosaurus inequalis skull, now attributed to Latenivenatrix
Artist's restoration of Saurornithoides (now Zanabazar ) junior
The feet of Borogovia
Troodontids were formally distinguished from pachycephalosaurs in the 1980s.
Two Paronychodon teeth
Limb bones of Tochisaurus
Artistic restoration of Sinornithoides youngi
Troodon eggs continued to attract scholarly attention in the 1990s.
In the 1990s, Thomas Holtz argued that troodontids were close relatives of the ornithomimosaurs (example pictured), although this is no longer widely accepted.
Sinovenator fossils
Illustration of Sinovenator with a human to scale
Artist's restoration of Mei
Artist's restoration of Anchiornis
Artist's restoration of Xixiasaurus
Artist's restoration of Gobivenator