Paleoecology of Albertosaurus

All carnivorous Albertosaurus fossils were found in the horseshoe canyon formation in Alberta. The age of this stratum is the Upper Cretaceous Maestre Ketian, about 67-73 million years ago. All the fossils of Albertosaurus come from the strata of 765,438+000-67 million years, from the late CAMBRIAN to the Maastricht stage. Directly below this stratum is the Zhang Xiong Formation, which is a marine deposit of the inland sea in the west. At the end of Cretaceous, due to the cold weather, the trench subsided, so the sea level fell and the horseshoe canyon stratum became land. However, this seaway fluctuates periodically and invades horseshoe canyon strata many times until it finally falls. Therefore, there are different sedimentary layers in horseshoe canyon strata, including offshore, coastal and coastal environments, such as lagoons, estuaries and tidal flats. Countless pieces of coal seem to be peat formed in ancient swamps. Like other vertebrates found in this area, the fossils of Albertosaurus were found in sediments of deltas and flood plains, where rivers used to flow.

The horseshoe canyon stratum is a famous fauna, and dinosaurs are the dominant organisms in this fauna, and the hadrosaurs account for half of them, including: Edmontosaurus, Ctenosaurus, and Yaguanlong; Ceratosaurus and Pterosauridae are common dinosaurs, accounting for one-third of the fauna; Ankylosaurus and Ankylosaurus are rare; There are all kinds of theropod dinosaurs in this area, such as Microodontosaurus, Diplodocus and Noctuidae. Adult Albertosaurus is the top predator in this area, and young Albertosaurus occupies its niche. In addition, Albertosaurus and its close relatives Tyrannosaurus Rex and Nanotyrannus can also meet, although their distribution areas rarely overlap.

Aquatic animals found in this area include fish: sharks, rays, sturgeons, bow-fin fish, eels and eel-like kiss fish; Reptiles in fresh water include turtles, E Long and crocodiles, such as Leidyosuchus and Stangerochampsa. Marine reptiles include plesiosaurs, a suborder of plesiosaurs. In addition, mammals such as multidentate and marsupial Rodtoron were also found in this area.