The data that indicate that the disaster was in the spring are different – annual rings of growth of some bones, chemical data on the availability of food
Well-preserved fossils of fish found in North Dakota provide information about one of the worst days in Earth’s history – the global disaster caused by a 12-kilometer asteroid that fell on the Yucatan Peninsula, Reuters reported.
The mass extinction it caused destroyed three-quarters of the species at the end of the Cretaceous, and conditions for the dominance of mammals, including humans, emerged.
Scientists have determined that this happened in the spring at the fossil site called the Tanis deposit, and in the northern hemisphere, including where the asteroid fell. They studied the bones of three sturgeon and three rowing fish that died within 30 minutes of the asteroid’s crash 3,500 kilometers away.
The analysis shows that hail from the glass hit the place. They found small spheres in the gills of the fish – molten material ejected from the impact of space, which crystallized before falling to earth. The fossils from Tanis also prove that a huge water wave has swept away all the inhabitants along the way. Among the dinosaurs that lived there was Tyrannosaurus Rex.
The data that indicate that the disaster was in the spring are different – annual rings of growth of some bones, chemical data on the availability of food.
Spring is a time of growth and reproduction for many organisms. This season is vital for the survival of the species, said study co-author Sophie Sanchez of Uppsala University.
In the southern hemisphere, it was autumn, a season when many creatures prepare for winter deprivation.
Dinosaurs have disappeared, along with their inherited birds, as well as many marine groups, including predatory reptiles that have ruled the seas. Survivors include rowing fish and sturgeon.
The asteroid has carved a 180 km wide crater. It has caused earthquakes, fires, shock waves in the air, seismic waves on the ground and huge waves in water bodies. Such waves with a huge amount of sediment reached the Tanis object 15 to 30 minutes after the fall of the asteroid and buried everything alive. The disaster did not end that day. The rising cloud of dust caused a climate catastrophe similar to a nuclear winter and blocked sunlight for years. This doomed countless species.