Ever heard the story about how the dinosaurs got extinct? Well, there are two versions of it that the scientists have been arguing about for since practically the dawn of time (or at least since the dinosaurs left the Earth).
According to the more popular version, an Ice age came and completely caught the dinos off guard, wiping them out entirely. Apparently, as much as it was a fearsome predator for its time, the t-rex couldn’t fight against the cold and is no more because of it.
Another version blames it all on the human race and, knowing our species, it may not be that far off. In fact, a new discovery in Bahamas may have just put some extra credence to this theory.
So, what’s this all about? Well, recently, a group of scientists located an underwater fossil site in the Bahamas, which help them better understand the forces that were at play when the dinosaurs disappeared and why this happened in the first place.
The conclusion they came to was that the human encroachment was far more devastating than the so-called “ice age”.
Lead author and curator of ornithology at the Florida Museum of Natural History David Steadman said the underwater fossils in Bahamas gave the researchers and “unparalleled snapshot at what the Ice Age life would have been on a Caribbean isle”.
Why are Islands Better for this Kind of Research?
Islands are actually better for conducting this kind of research since their isolation allows scientists to learn more about a certain species and what factors lead to their development or demise. It’s the same logic Charles Darwin went with when he studied animals at the Galapagos Islands.
Now back to the humans and how we fit into all of this. Studies have shown a clear pattern – as soon as human species gets on the island, another species disappears off the face of the Earth. However, so far the scientists could not put the whole blame on humans since there are also numerous natural and other factors that can and do contribute to all of this.
By studying the underwater fossil site in the Bahamas, researchers are able to get a clearer picture and figure out what was worse for mammoths or sabertooth cats.
The site itself was discovered by Brian Kakuk, an experienced scuba diver (and co-author of the study) on the island of Abaco.
Mr. Steadman said the following about the underwater fossil site in the Bahamas:
“As the first fossils started to come… I could tell that this was a really unusual site and could probably inform us about things that no other site on a Caribbean island, that any of t the previous sites cold.”
What Was Discovered?
The site contains over 5,000 fossils from 96 different species (63 birds, 13 fishes, 11 reptiles and 8 mammals). What’s particularly interesting about these underwater fossils in Bahamas was that 39 of them are from species that have disappeared from the island.
Since the fossils were submerged in water, they were likely placed there sometime during the Pleistocene era, so before the sea levels rose. That means the underwater fossils in Bahamas over 11,700 years old.
Now the researchers can compare the fossils from Abaco with more recent bones found on the island from the Holocene era (after 11,700) and learn which of the two survived the climate change surrounding the transition and which one survived the human presence.
According to scientists, out of 39 extinct species 17 vanished due to climate change. That’s less than 44 percent). The other 56 percent, or 22 species, managed to survive the Ice Age, but not the arrival of humans.
This leads to a conclusion that the Ice Age was not to blame for the extinction of most of these species, which is even more surprising given the fact that the Abaco Island shrunk tenfold from its original size because of the water level going up. In fact, the island was about 17,000 square kilometers big before the climate change and is not “only” 1,214 square km big.
The irony of many species surviving such a cataclysmic change, only to be wiped out by human predators was not lost on Steadman, who said:
“In a way there’s some real irony here because any of the species that were alive a thousand years ago on Abaco when people first arrived were pretty darn resilient – other words, they’re the ones that could handle the island getting smaller, the habitat changing and all that. But when people show up and they start burning the forest in the dry season and things like that, that’s a tough one to adapt to.”
Steadman also added they will try and study more underwater fossils around the Bahamas in order to get to the bottom of this.