You might think that we would be walking with dinosaurs if the famous Chicxulub Impactor never hit. That we would be having pet raptors, and we’d be walking to school with T. rexes. However, I am sorry to disappoint any dino lovers out there – if the asteroid missed, it would be very unlikely that humans would have ever evolved. As it turns out, evolution is complicated. Very complicated. To find out what would have happened, we first have to look at the basics of how humans evolved.
You might think that we’d be walking with dinosaurs if the famous Chicxulub Impactor never hit. That we’d be having pet raptors, and we’d be walking to school with T. rexes. However, I am sorry to disappoint any dino lovers out there – if the asteroid missed, it would be very unlikely that humans would have ever evolved. As it turns out, evolution is complicated. Very complicated. To find out what would have happened, we first have to look at the basics of how humans evolved.
The Pre-Asteroid Era
The Pre-Asteroid Era
Before the asteroid strike, humanity’s ancestors were little more than small squirrel-like rodents which lived on a diet of insects and seeds. They were common prey, and were unable to flourish, as despite their fast reproductive rate, they were kept in check by other competitors.
Before the asteroid strike, humanity’s ancestors were little more than small squirrel-like rodents which lived on a diet of insects and seeds. They were common prey, and were unable to flourish, as despite their fast reproductive rate, they were kept in check by other competitors.
Meanwhile, conventional dinosaurs were large, strong and able to grow and dominate the planet. That is, until the asteroid struck. An asteroid around 10-15 km in diameter, smashed into the earth at a mind-blowing 20 km/s. It unleashed around 10²³ joules of energy (1,000,000,000,000,000,000,000,000 J), equivalent to around 100 million megatons of TNT (100 million million tons), wiping out 75% of all species.
The blast was 200 million times more powerful than the world’s most powerful nuclear weapon, the Tsar Bomba (when it was detonated, windows shattered from over 900 km away, and 3rd degree burns could be sustained as far as 100km from the explosion site). The asteroid left a crater ~180km in diameter.
From Rodents to Humans: The Post Extinction Era
From Rodents to Humans: The Post Extinction Era
Thankfully, that 75% included all non-avian dinosaurs, the main source of fear for our rodent ancestors. These hardy squirrel-like mammals had an extremely flexible diet, allowing them to evolve to survive on the little food that was available.
Most plant life was annihilated as well, spelling doom for a large amount of creatures that depended on them. Our ancestor wasn’t one of them. In the next 100,000 years, they recovered to the extent that their population was not only stable, but growing exponentially.
The absence of most of their main predators opened the pathway for evolution to run wild, going from early mammals, to primates, to, to hominins and finally the Homo sapiens sapiens we know today. Not being forced to hide up in trees, they had the time and capacity to develop bipedalism, which allowed them to cross vast plains quickly, freeing their hands to carry other items. Some people think this led to the evolution of the human intelligence we have today.
Dinosaurs over Rodents - What If the Asteroid Missed
Dinosaurs over Rodents - What If the Asteroid Missed
However, if this fateful asteroid missed the Earth, it is very possible humans could have remained small rodents. Without anything to reduce the population of the dinosaurs, our ancestors would have been in more danger than ever. Their population would not have been able to grow and evolve as much as it had been able to when the asteroid did hit. Also, being continually hunted, they would likely have to continue their tree-living habits in order to survive. Perhaps some other dinosaur species might have evolved super-human intelligence beyond that of humans instead.
Fortunately we will never know! It turns out that the existence of humans may depend on one cosmic accident in Earth’s history! Comment down below what species do you think would have reigned the Earth if the Chicxclub Impactor never hit, or feel free to ask any questions regarding this article 😉
