“Ghost” fossils preserve an unforgettable record of ancient life on Earth like hell
Ghost-like traces of small plankton-like creatures were found infested in prehistoric sea sediments at a time when such creatures were thought to be extinct. Traces of so-called nanofossils reveal that organisms have survived the acidic waters caused by climate change and can provide clues as to how modern organisms can withstand rising seawater temperatures. The researchers said it was sexual.
Nannofossils are the remains of marine plankton called cox-oh-LITH’-oh-fours and belong to this class. Prymnesiophyceae And even today it is at the bottom of many marine food chains. Each of these unicellular algae-like organisms is less than 0.001 inches (30 micrometers) wide and is surrounded by a hard layer of geometric calcium scale. Faculty of Earth Sciences, University of Bremen In German. And these nanofossils are incredibly abundant.
“There are far more nanofossils than any other type of fossil,” Paul Bowen, a microfossilist at the University College London, UK, and co-author of the new study, told Live Science. “That means we can really be statistically robust because we see many of them.”
When these small plankton die, they sink to the seabed, where calcium shells slowly accumulate. Over time, these piles of white mineralized scales, known as coccoliths, are pressed together to form a wall of chalk. According to Brown, a typical example is the white cliffs of the famous Dover in England. “The white chalk cliffs are almost 100% nanofossils, so they are white,” Baun said.
Related: Thanks to the new fossils, we finally found out how the trilobites mated.
However, fossil records show that coccolithophores suddenly disappear and mysteriously return millions of years later. “These rapid changes change from almost pure white deposits to black deposits,” says Bown. These points are consistent with the ancient marine warming event, where seawater became more acidic as it reacted with the increase in carbon dioxide from the atmosphere. When the pH of the sea dropped during these events, it was eaten up with coccolithophore calcium shells so that vinegar could dissolve the eggshells. National Oceanic and Atmospheric Administration (NOAA).
Scientists once thought that most species of calcium-coated plankton in these acidic oceans were wiped out in large numbers and replaced with shellless species.
Sam Slater, co-author of Bown, a microfossilist at the Swedish Museum of Natural History in Stockholm, previously concluded that it was pretty much the same. However, Slater then studied another study looking for traces of ancient pollen while examining black deposits from Jurassic (201-145 million years ago) warming events. I noticed something strange inside. Under a powerful microscope, Slater detected small geometric traces in the rock and noticed that these traces were precisely shaped like coccolithophores.
Slater contacted Bown and a few other experts to assist in the investigation. Sure enough, the rock was engraved with coccolithophore. “These were nicely preserved impressions. We were able to identify them down to the species level,” Bown said.
Intrigued by this discovery, researchers then found fossil deposits from other Jurassic sites around the world and two warming events in the Cretaceous (145-66 million years ago). I examined the sample of. “And everywhere I looked, I found these impressions, the fossils of these ghosts,” Bawn said.
These results suggest that, contrary to previous studies, some coccolithophores survived the catastrophic ocean acidification and extinction of warming, even if other species became extinct. However, due to the low pH of the sea, the shells melted after death and they were erased from fossil records.
According to researchers, this information could help shed light on the catastrophe of the current climate. Smithsonian.. If coccolithophores can adapt to warmer and more acidic conditions, it may be good news for modern creatures further upstream in the food chain.
However, Bown warns against equating ancient warming events too closely with modern climate change, according to a study published in the journal in 2019. Paleoceanography and Paleoclimatology..
“It’s a matter of caution, and you have to be careful about how you go and read the rocks,” Bown said.
The new study was published in the journal on May 19th. Chemistry..
Originally published on Live Science.
“Ghost” fossils preserve an unforgettable record of ancient life on Earth like hell
Source link “Ghost” fossils preserve an unforgettable record of ancient life on Earth like hell
