Find out the season in which the meteorite that killed the dinosaurs fell

Sixty-six million years before our era. Yucatan Peninsula. Animals of all fur and parables from the Mesozoic in search of food and resources. They have just come out of winter and are relaxing with more daylight hours. It is a time of prosperity, growth and courtship. You will see how someone comes along or something happens that spoils her. that happens. A massive asteroid, Chicxulub, is located at that point in the Northern Hemisphere, causing the extinction of 76% of species, including all non-avian dinosaurs, pterosaurs, ammonites and mollusks, and most marine reptiles.

Thousands of miles away, in North Dakota, paddle fish were now going about their daily routine in a lake or reservoir. The effect took them, like everyone else, by surprise. The blast wave takes between 15 and 30 minutes to reach its source. In an instant, the paddlefish flies with the wave pulling on it, until it is buried under stones and boulders.

Several billion years later, in 2022 AD, humans dug up the fossils of these fish. The Tanis site in North Dakota preserves an extraordinary collection of life-sustaining mass die-offs from the late Cretaceous period, and most of the large fossils found there are direct victims of the Polyade effect, like them.

From the structure of the growth of the bones of these fish, humans believe that it must have been spring at the time. It certainly wasn’t winter, there were also traces of plankton, not so much. Plankton grow between spring and fall. The fact that there were not many plankton in the digestive system of the fish nor in the environment, could be due to the fact that the disaster occurred in that season.

Humans and paleontologists have reconstructed the scene and how those fish died. Contrasting data, using 3D modeling of fossil bones, dissecting them and performing isotope tests to approximate their age, prove their thesis. The meteorite fell in the spring and those fish died on the same day about an hour after hitting the Yucatan River. they publish your discovery today in natureand closing one of the unknowns that other paleontologists have sought for years.

“The mass and selective extinction of the masses of dinosaurs particularly affected all those that lived in the northern hemisphere. There are very few records in the southern hemisphere, but our hypothesis is that the meteorite fell in the spring, which is the time when it woke up from winter. It began Everything, and the animals are likely to be most endangered, or in places that made them more vulnerable,” explained Melanie While, the paleontologist at Uppsala University, who discovered the fish, and one of the authors of the research.

“The springtime for this catastrophic effect coincided with a particularly sensitive time for many species in the northern hemisphere that reproduce and grow during the spring. Ecosystems in the southern hemisphere, damaged during the fall, appear to have recovered. Twice as fast as those in the In the Northern Hemisphere,” the study pools.

what happened after that?

The authors report: “The effect of Chicxulub bolide triggered a global heat pulse that resulted in widespread wildfires. After this heat wave, the last northern Mesozoic spring gave way to a winter of global impact.” “In the days or months following the impact, its momentary effects, such as intense infrared radiation caused by returning meteor ejections, wildfires, and the spread of sulfur aerosols causing acid rain, should have mostly affected the surrounding environments.” They add.

For the human paleontologists who unraveled this mystery, the event must have occurred at a point particularly sensitive to biological life cycles in the northern hemisphere. “In many taxa, annual reproduction and growth occurs during the spring. Species with longer incubation periods, such as non-avian reptiles including pterosaurs and most dinosaurs, are probably more susceptible to sudden environmental disturbances.” from other animal groups, such as as birds.”

The extinction was massive but selective, and those who survived or managed to emerge were either those who managed to protect themselves underground, dormant by going into hibernation (in the southern hemisphere) or culturing (in the northern hemisphere) the following months. And those who survived climate change then. In fact, some species of birds and crocodiles, such as some amphibians and mammals, enter the stage of growth or dormancy in the summer, due to heat or drought, and come from masses that survived the slaughter and have evolved until today.

Paleontologists are confident that separating the short- and long-term impacts that occurred with the Chicxulub impact will help determine the extinction risks and patterns of environmental degradation caused by upcoming global climate change.