Could the smartest raptors have been the biggest ones? This has become a burning issue for paleontologists, thanks to the recent find of a gigantic troodontid named Fujianipus yingliangi , whose huge footprints, found in what used to be a muddy riverbank, have reset the standards for the largest possible sizes of raptors. Measuring between 36 centimeters long, these tracks, found in what used to be a muddy riverbank, are the largest raptor tracks ever reported, suggesting a length of about 5 meters with a hip height of more than 1.8 meters.
The Longxiang dinosaur tracksite in Fujian Province is a fossil treasure measuring 17,000 square feet in size and featuring more than 240 dinosaur tracks. However, in the year 2020, the discovery of five giant two-toed tracks was made among them. This was revealed by Lida Xing, who led the research. You know a raptor track when you see it. But these tracks are different from any that have ever been found. explained Lida. The impression of the toe pad is very distinct in the discovered fossil. This is a unique attribute in the field of ichnology.
These belong to a member of Troodontidae, which is a family of feathered, bird-like theropods characterized by a considerable level of encephalization quotient or brain-to-body mass ratio. As a rule, Troodonts were 1 to 2 meters long, but it compares favorably to the largest representative of Deinonychosaurs like Austroraptor and Utahraptor. As quoted by paleontologist Anthony Romilio regarding this discovery, it was much skinnier and smarter than the chunky dromaeosaurids you know and love, but easily bigger than the ones you saw in Hollywood.
Both in its toe shape and its function, the two-toed track represented the characteristic locomotion pattern of the deinonychosaurs, who, with three toes, raised the elevated second toe with the hooked claw, thus allowing only the first and third toes to contact the ground. As regards the Fujianipus tracks, the dimensions of the claws and the heights of the tracks suggest the capacity to pursue and prey on a much larger diet than other members of the troodontids.
Dating and analyzing these tracks requires detailed stratigraphic and sedimentologic analysis. The mud at the Longxiang riverbank was just firm enough to take detail impressions before being hardened by the sun, which is the right kind of sediments for making tracks, which will be baked hard by the sun after being imprinted with considerable detail. Undertracks or natural casts might be formed below or inside the tracks, supplying extra information on the functions involved.
Dating and analyzing these tracks require detailed stratigraphic and sedmentological analysis. The mud at the Longxiang riverbank was just firm enough to take detail impressions before being hardened by the sun, which is the right kind
Our discovery of giant troodontids in Australia fills a previously unexplored zone in this evolution story and suggests that these giant apex predators were more common and distributed over a wider geographic area, comments Dr Westcott. Our findings suggest these raptor giants roamed much further south and were more widely distributed, states paleontologist Michael Archer, co-author of the study and colleague of Mannion and Beth Stewart. The fossil discovery of giant troodontid theropod dinosaurs in Fujian Province in southern mainland China is of great significance, wrote Chinese media of this global discovery. “Our findings suggest these raptor giants roamed much further south and were more widely dispersed.” explain scientists.
The discovery also increases the ecological diversity of raptors that have hitherto been known. The great spectrum, from sparrow-scaled Microraptor in South Korea to the giant Fujianipus, presents the degree of flexibility that deinonychosaurs have demonstrated. Large-bodied troodonts have probably played roles that were at least in part coincident with that of tyrannosaurs, according to Steve Brusatte, who studies the subject at the University of Edinburgh: It seems that during this phase, these two legendary groups of dinosaurs, the tyrannosaurs and the raptors, were each competing for that medium-sized predator slot.
The Cretaceous Fujian environment could support a hunter like this. It has been reconstructed that Cretaceous Fujian supported warm climatic conditions, a high level of sea, and a riparian vegetation belt characterized mainly by conifers, ferns, and cycads. This supported herbivores to feed in plenty, which made up the main diet of top predators and mesopredators. It appears that a track site like Longxiang contained a variety of tracks.
It has been made possible through comparative studies of ichnological researches conducted worldwide that the tracks made by Fujianipus are unique in their morphology compared to other two-toed tracks registered in Asia, America, and Europe. The uniqueness and unusual magnitude of Fujianipus yingliangi make a great contribution in studying raptor biology and their role in late Cretaceous times.
