Old School Dilophosaurus
St. George meet Dilophosaurus
This sculpt is decidedly old school, laden with scales and nary a hint of feathers. Being on the “primitive” side of the #theropod tree, a fair question is when did feathers appear?
If they hold up being on ornithischians(#Kulindadromeus) then they developed multiple times. Or, are they plesiomorphic for #dinosaurs? Perhaps even at the #dinosaur/#pterosaur split? If the latter then I suppose any dinosaur could have ‘em. If multiple times, maybe the feathers aren’t homologous but rather analogous, like flight and vision in trilobites vs vertebrates?
If the putative protofeathers on ornithischians are separately derived than the feathers in theropods then whence do they appear in theropods? Down low or in more derived taxa? Did #Triassic #theropods sport plumage?
This Arizona #Jurassic (190 mya) giant reached 25’+, 1,000 lbs+ and was the “two-crested lizard” of Welles 1970. It is known from a number of partial skulls and skeletons.
For awhile there was #Dilophosaurus sinensis, a two-crested critter from China’s Early Jurassic, but it is now considered to be #Sinosaurus, the crests being evolutionary convergence. Fossil Crates has a rentable cast!
Some characters, like cranial ornamentation, can converge such that the exterior takes the same shape on multiple taxa, but the bones comprising the structure will be slightly different.
However, other structures, like cell walls, DNA helix, eyes, feathers, aren’t as easy to come by genetically, when they tend to stay consistent.
Found in the early 1940s, twas named a new species of #Megalosaurus in 1954. It wasn’t until the mid-60s it was fully realize it had a heretofore unknown feature: two crests on its head! Thus the name.
Until 2020, it competed in the best-known/least-known category, with lots of bones but no proper description or analysis. Thankfully, Adam Marsh and Tim Rowe’s 2020 treatise solved lots of these issues. There is more to do, but now it is one of the better describes theropods.
This display also at the @utahdinosaurs at the St. George Dinosaur Discovery Site at John’s Farm.
#FossilCrates