Many theories exist explaining the extinction of Dinosaurs but the most agreed upon is the asteroid explanation
It turns out that the frogs’ survival is due to the extinction of dinosaurs just like their extinction paved way for successful human evolution
If the asteroid catastrophe would not have happened, 88% of today’s frog’s species would not be here today
July 04, 2017: A study carried out by American and Chinese biologists has concluded that had it not been for the extinction of dinosaurs by the asteroid, 88% of frog’s species we have today would not exist. The frogs’ survival was a benefit reaped out of the death of dinosaurs.
The Asteroid that hit the planet wiped out three-quarters on animals on the Earth. The extinction is popularly known as the Cretaceous-Paleogene (K-PG) boundary.
The asteroid which met the Earth 66 million years ago had a direct impact in wiping out dinosaurs from the face of the planet, however, the frogs actually benefitted out of it. The emergence of frogs can be traced back to 200 million years.
The resilient creatures were able to take advantage of an evolutionary vacuum that was created as a result of the destruction. It has been observed that 9 out of 10 frog species that exist today evolved from just three frog lineages that survived the asteroid impact, mentioned ANI report.
Frogs are “master survivors” stated David Wake, co-author of the research paper published in Proceedings of the National Academy of Science. They were quick to take to trees which at the time were “evolving to their full flowering”. The team of Gene researchers studied 95 sets of genes from 156 frog species.
Today, frogs are the most diverse group of vertebrates with more than 6,700 species discovered.
– prepared by Saksham Narula of NewsGram. Twitter: @Saksham2394
Giant rocks from space are falling from the sky more than they used to, but don’t worry.
For the past 290 million years, large asteroids have been crashing into Earth more than twice as often as they did in the previous 700 million years, according to a new study in Thursday’s journal Science.
But no need to cast a wary glance up. Asteroids still only smack Earth on average every million or few million years, even with the increased crash rate. NASA’s list of potential big space rock crashes shows no pending major threats. The biggest known risk is a 4,200-foot (1.3-km) wide asteroid with a 99.988 percent chance that it will miss Earth when it whizzes very near here in 861 years.
Tell that to the dinosaurs. Most scientists think dinosaurs and a lot of other species went extinct after a huge space rock crashed into Central America about 65 million years ago.
“It’s just a game of probabilities,” said study lead author Sara Mazrouei, a University of Toronto planetary scientist. “These events are still rare and far between that I’m not too worried about it.”
Mazrouei and colleagues in the United Kingdom and United States compiled a list of impact craters on Earth and the moon that were larger than 12 miles (20 km) wide and came up with the dates of them. It takes a space rock that’s half a mile (800 meters) wide to create holes that big.
The team counted 29 craters that were no older than 290 million years and nine between 291 million years and 650 million years old.
But we can see relatively few big craters on Earth because the planet is more than 70 percent ocean and past glaciers smoothed out some holes, said University of Toronto planetary scientist Rebecca Ghent, a study co-author.
Extrapolating for what can’t be seen brings the total to about 260 space crashes on Earth in the last 290 million years. Adding in other factors, the science team determined that the current space crash rate is 2.6 times more than the previous 700 million years.
Craters older than 650 million years are mostly wiped off on Earth by glacial forces so the scientists used impact craters on the nearby moon as a stand-in for holes between 650 million and 1 billion years old. The moon is a good guide for estimating Earth crashes, because it is close enough to be in the same bombardment path and its craters last longer.
So what happened nearly 300 million years ago?
“Perhaps an asteroid family was broken up in the asteroid belt,” Mazrouei speculated. The space rocks then headed toward the Earth and moon, and the planet got slightly more because it is a bigger target and it has higher gravity, Ghent said.
Outside scientists are split about the research. Jay Melosh at Purdue said he found the number of craters too small to come to a reasonable conclusion, but Harvard’s Avi Loeb said the case was convincing.
Humans might not have emerged without mass extinctions from space rocks about 250 million and 65 million years ago, Loeb said in an email, adding, “but this enhanced impact rate poses a threat for the next mass extinction event, which we should watch for and attempt to avoid with the aid of technology.”
“This demonstrates how arbitrary and fragile human life is,” Loeb wrote. (VOA)