Written by Mike Lee, Professor in Evolutionary Biology (collectively appointed with South Australian Museum), Flinders University.
This article was first published in The Conversation.
The explosion from this was so huge, it led to global earthquakes, tidal bores, bushfires, and even toxic rain.
The asteroid hit at one of the worst possible locations, where the rocks might quickly be “took off” (or vapourised). This tossed up massive amounts of dust into the sky, shutting out the Sun for numerous months and sending Earth into a long, dark, and freezing winter.
Without sunlight, the green plants died, followed by the plant-eating animals that ate them to survive, and the meat-eaters that ate the plant-eaters.
Credit: Michael Lee
Researchers think three-quarters of all the various kinds (species) of animals on Earth were cleaned out– consisting of most dinosaurs.
Some managed to make it through for a variety of factors.
One important group of dinosaurs sailed through, helped by their ability to fly and find food in distant places. Their plumes secured them from the cold, and their beaks let them eat buried seeds found near dead plants.
Amazingly, these dinosaur survivors are still with us today. We call them birds!
A battle-scarred saltwater crocodile resting near the Daintree River in North Queensland. Credit: Michael Lee
Crocodiles had some secrets to survival
Crocodiles were another group that famously made it through the asteroid. Obviously, they cant fly, do not have feathers, and dont consume seeds! However they had other tricks to success.
Firstly, crocodile bodies utilize extremely little energy. They lie around a lot, breathe slowly and even have a really sluggish heart beat. This is how they can hold their breath undersea for more than an hour.
It also implies they can go without food for months, and often more than a year. When food (such as other animals) ended up being tough to discover once the asteroid hit, this would have been very valuable.
Dinosaurs, on the other hand, were typically more active, which indicates they required more energy– particularly meat-eaters like Velociraptor. Without food, they would have passed away rapidly.
Dinosaurs such as Velociraptor would have struggled to survive without much food after the asteroid hit. That is, if they survived in the first location.
Crocodiles also lived in places where losing green plants didnt make a huge distinction. Consider a grassland or a forest (where lots of dinosaurs lived): if the plants there pass away, then all the animals that require them die too, including the meat-eaters which are entrusted no food.
However the crocodile survivors mainly resided in locations like rivers, lakes, and coasts. The animals residing in these locations do not need green plants as much. Dead plants and animal material washes in from surrounding land, which is eaten by small creatures, which are then consumed by larger animals consisting of crocodiles.
So unlike dinosaurs surviving on the land, crocodiles in a river would not have starved as quickly as the green plants died.
Our mammalian forefathers likewise made it through
A comparable reason helps describe why people forefathers likewise survived the asteroid effect. These were the small mammals that lived near the end of the age of dinosaurs, which eventually gave increase to all the various kinds of mammals around today (including humans).
They were generally little, rat-like things that scurried about in the dead leaf litter on the ground, consuming pests and worms. These tiny creatures relied not on living green plants, but on dead leaves and bark falling from the trees, or being blown and cleaned in from in other places.
Just like the crocodiles, our small ancestors survived the asteroid partly due to the fact that they didnt depend greatly on living plants. An advantage too: these fortunate survival skills are the factor you and I are here today!
There are two primary reasons crocodiles survived the asteroid that eliminated the dinosaurs. Crocodiles can live for an extremely long time without food. Second, they lived in places that were the least impacted when the asteroid struck Earth.
Crocodiles were another group that notoriously survived the asteroid. The crocodile survivors mainly lived in places like rivers, lakes, and coasts.
There are two main reasons crocodiles made it through the asteroid that killed the dinosaurs. Initially, crocodiles can live for a long time without food. Second, they lived in places that were the least affected when the asteroid hit Earth.
When the asteroid hit earth
About 66 million years back, dinosaurs ruled Earth. But then a huge asteroid, more than 9 kilometers wide, knocked into the shallow sea near what is now Mexico.