I still remember that day vividly… in the middle of excited rumours at the SVP that year, there it was: the cover of an issue of Nature in 1997 with the first published photograph of the fossil of Sinosauropteryx on the cover… right at the newstand!… The fossil that would really change it all. That was officially the first fossil that unequivocally showed feathers on a non-avian dinosaur… and got a lot of people fuming! “They were NOT feathers” fiercely argued the “Birds are not dinosaurs camp”… but after all these years, analyses anfter analyses they were proven wrong and the filaments or “protofeathers” that surrounded like a halo the skeleton made it look almost exactly Messel-like… microscopic study corroborated ot and now we even have the possible colours of the protofeathers!
The typical specimen of Sinosauropteryx was about 60 cm long. A bigger specimen was reported as 1 meter… and other similar species like Scalliopteryx were even bigger. But… there was an issue still pending… Currie and Chen 2001 reported that:
“The [smaller] specimens of Sinosauropteryx prima show skull and orbit proportions, and bone texture typical of immature stages.
In April 2024 Andrea Cau published a photo of an undescribed 3.8m long (!) Yi Xian specimen labelled as Sinosauropteryx that is housed in a Chinese museum. The hand and foot are distinct from the holotyoe and the tail is relatively shorter. Legs are also typically longer and theropodian. Quoting the description: ” According to Cau’s caption: “This is the so-far-undescribed “largest Sinosauropteryx”, an amazing 3.8 m long (!) specimen housed in a Chinese museum and claimed to be a Sinosauropteryx. Although not yet included in my matrix, this specimen confirms the hypothesis developed in my latest paper that “compsognathids” are not adult morphs of small size, but juvenile semaphoronts of larger tetanurans. This specimen would surely improve the systematic placement of the Jehol Biota “compys”. “After testing in the LRT this specimen indeed nests with the smaller specimens.”
Are we now solving the Phil Currie and Chen’s observations from the early 200o’s and we have finally found an adult or subadult Sinosauropteryx while the original specimens were immature individuals? Celebrating the possibility here’s my take on a family of Sinosauropteryx wading a Yi Xian lake’s toxic waters… and a comparison of three specimens… from the smallest to the biggest yet found. Please note that this is still not completely verified… but in the meantime we have the picture of an upscaled parent of an all time favourite dinosaur!… warning, this may change in the future!
In the meantime> a kind reminder of an unmissable event: