Researchers assume that the dinosaurs would have been largely unscathed by the impact of the Chicxulub asteroid – had it only hit Earth a little later.
Chicxulub Pueblo – Time and place often play their part in whether something good or bad happens to us. Who does not know it? If you had been a minute earlier, you would have got the right bus to work, would have been in the office on time and would not have had to sneak into the meeting ashamed and delayed. Or: If you had stood half a meter further to the left, the hairstyle would have been spared from the bird’s stool. “Wrong time in the wrong place” coincidences of this type are annoying but tolerable.
An incident 66 million years ago was apparently less bearable and therefore all the more annoying for some species: the impact of an asteroid near Chicxulub Pueblo on the Yucatec coast in Mexico. For supporters of the impact theory, this is said to have been decisive for the extinction of the dinosaurs – and that the climate on earth changed massively.
Or to put it more cautiously: You assume that a decisive event 66 million years ago brought consequences that were so destructive that large parts of the flora and fauna did not survive them. The Chicxulub crater is also believed to have formed 66 million years ago. It is therefore possible that the very asteroid impact was responsible for the devastating developments on Earth.
Dinosaurs may just have been unlucky
But now comes the particularly annoying (for the dinosaurs): If the 15-kilometer asteroid had hit only half a minute earlier or later, it would have landed somewhere in the sea – and, apart from tsunamis, fires and other relatively minor environmental disasters, would probably have a lot less destruction done. Scientists came to this assumption as early as 2017. The decisive factor was not necessarily the size of the celestial body, the speed, the impact of an estimated 10 billion Hiroshima bombs, or the size of the crater that was left behind. The decisive factor was the location of the impact and even the angle of the impact, as researchers have shown in the journal Nature.
A team led by scientists Joanne Morgan and Sean Gulick pointed out in 2017 that the asteroid hit rock layers with high concentrations of hydrocarbons and sulfur. When the particles were thrown high into the air, they mixed with water vapor and created a “global winter”, as the BBC describes the result. The cloud of soot must have been so thick that the sun’s warmth and light couldn’t get through.
“An impact in the nearby Atlantic or Pacific Ocean would have meant less evaporated rock – including the deadly gypsum. The cloud would have been less dense and sunlight could still have reached the surface of the earth, which means what happened next could have been avoided, “evolutionary biologist Ben Garrod told the BBC.
Chicxulub Crater: According to researchers, dinosaurs must have died suddenly
“In this cold, dark world there was no more food in the oceans within a week, and shortly afterwards there was also no food on land. Without something to eat anywhere on the planet, the huge dinosaurs had little chance of surviving, ”continues Garrod.
Many fossils can be found close to the surface, such as in a quarry in the US state of New Jersey, where researchers have excavated around 25,000 fossils. “All of these fossils are in a layer that is less than four inches thick,” paleontologist Ken Lacovara told the BBC. “You died suddenly and were quickly buried. That tells us that this is a moment in geological time. Those are days, weeks, maybe months. But it is not thousands of years, it is not hundreds of thousands of years. In essence, it is an immediate event, ”summarized the researcher.
As bad as it seems that at that time more than two thirds of the species living on earth were probably wiped out: Under the circumstances at that time there would probably have been little room for mammals. For us humans, the Chicxulub asteroid probably came to the right place at the right time. (ial)
