Earth Science Club of Northern Illinois - ESCONI

SciNews: 305-Million-Year-Old Fossil Shows Parent Caring for Its Offspring #carboniferous

An artist’s impression of an adult and a juvenile Dendromaia unamakiensis. Image credit: Henry Sharpe.

SciNews has a piece about an ancient synapsid with evidence that it cared for its young.  The animal, called Dendromaia unamakiensis, lived about 305 million years ago in what is now Cape Breton Island, Nova Scotia.  This find consists of both an adult and an associated juvenile which were found inside a fossilized tree stump.  Evidence of behavior is rare in the fossil record, which is why this is a such a valuable find.  The details of the discovery was published in a paper in the journal Nature Ecology & Evolution.

“Parental care is a behavioral strategy where parents make an investment or divert resources from themselves to increase the health and chances of survival for their offspring,” said paleontologist Professor Hillary Maddin and her colleagues from Carleton University and Fundy Treasures.

“While there are a variety of parental care strategies, prolonged postnatal care is amongst the most costly to a parent.”

“This form of parental care is particularly common in mammals, as all mammalian offspring demand nourishment from their mothers.”

“However, there is still little understanding of the evolutionary history of this behavior.”

SciNews: Paleontologists Uncover Fossilized Remains of Baby Ornithopod Dinosaurs in Australia #dinosaurs

An artist’s depiction of the ornithopod dinosaur Weewarrasaurus pobeni tending its nest. Image credit: University of New England.

SciNews has a story about the fossils of baby Ornithopod dinosaurs discovered in Australia.  The animals are baby Weewarrasaurus pobeni dinosaurs, that lived about 100 million years ago during the middle Cretaceous period.  Southeastern Australia, where these dinosaurs lived, was much closer to the South Pole at the time.  These specimens reveal important insights into high-latitude breeding in Gondwana.  A recent paper in journal Scientific Reports has all the details.

The newly studied fossils belong to a species of small-bodied ornithopod dinosaur very similar to Weewarrasaurus pobeni.

To estimate the individuals’ age, the researchers used growth rings in the dinosaur bones, similar to the rings in a tree trunk.

“Age is usually estimated by counting growth rings, but we couldn’t do this with our two smallest specimens, which had lost their internal detail,” said Justin Kitchener, a PhD student in the School of Environmental and Rural Science at the University of New England.

“To get around this, we compared the size of these bones with the size of growth rings from the Victorian dinosaurs. This comparison confidently places them at an early growth stage, probably prior to, or around the point of hatching.”

Approximately 100 million years ago, when these dinosaurs were being born, Australia was much closer to the South Pole.

“Southeastern Australia would have been between 60°S and 70°S, equivalent to modern day Greenland,” the scientists explained.

“Although the climate at these latitudes was relatively warmer than they are today, like some Antarctic penguins, these dinosaurs would have endured long dark winters and possibly burrowed or hibernated to survive.”

FOSSIL Project Fall 2019 Newsletter

Volume 6, Issue 3, Fall 2019| FOSSIL Project Newsletter Fall 2019

• FOSSIL Project Updates by Sadie Mills
• 11th North American Paleontological Convention: Perspectives from the Community
  • Ian D. Browne, post-doctoral fellow
  • Jennifer Broo, educator
  • Gloria Carr, amateur
  • Eleanor Gardner, former FOSSIL Project Coordinator
  • Kyle Hartshorn, amateur
  • Bill Heim, amateur
  • Bill Heimbrock, amateur
  • Jack Kallmeyer, amateur
  • Jayson Kowinsky, educator, amateur
  • Adriane Lam, graduate student
  • Cindy Lockner, amateur
  • Lisa Lundgren, former FOSSIL Project graduate student
  • Isaac Magallanes, graduate student
  • Linda McCall, amateur
  • Victor Perez, graduate student
  • Jeanette Pirlo, graduate student
  • Denise Porcello, educator
  • Sarah Sheffield, university faculty
  • MacKenzie Smith, graduate student
  • Matthew Speights, amateur
  • Michael Ziegler, graduate student
• Social Paleontology and FOSSIL’s Contributions to Research on Learning by Kent Crippen, Lisa Lundgren & Richard Bex
• myFOSSIL eMuseum and Curation Team by Jennifer Bauer
• Reflections on the FOSSIL Project and Future Directions by Bruce MacFadden

NatGeo: Earth has had more major mass extinctions than we realized #massextinction

A temple sits perched on Emeishan Mountain in Sichuan Province, China. The surrounding countryside includes the Emeishan Traps flood basalt, which marks the end of the Guadalupian epoch.

PHOTOGRAPH BY DBIMAGES, ALAMY STOCK PHOTO

National Geographic has a story about Earth's mass extinctions.  The current biodiversity crisis is usually referred to as the "sixth mass extinction".  There is even a book by that name.  Of the five previous extinctions, the worst was the one at the end of the Permian.  In a paper in the journal Historical Biology, Michael Rampino and Shu-Zhong Shen argue that the end-Guadapulian extinction, which occurred 259 million years ago in the middle Permian, should be considered a major extinction event.

In 1982, quantitative paleontologists Jack Sepkoski and David Raup at the University of Chicago took stock of the Earth’s worst mass extinctions, naming them the Big Five. That set includes the end-Permian, the greatest extinction event of all time, which occurred around 252 million years ago and eliminated 95 percent of marine species.

At the time, the carnage of the end-Permian overshadowed another extinction event just eight million years earlier at the end of the Guadalupian epoch. Over the last three decades, though, geologists have been digging deeper into the end-Guadalupian, and it’s more widely recognized as a distinct crisis. Now, some scientists are arguing that this ancient die-off was big enough to rank among the pantheon of past apocalypses, and they propose renaming the group of major extinction events the Big Six.

In the history of life, there have been many flameouts and setbacks. But by singling out and studying the biggest ones, geologists can begin to unearth patterns and search for common causes. Increasing evidence suggests that many global extinction events were associated with oxygen-depletion in the oceans, a symptom of greenhouse warming, and that has worrying implications for the present-day effects of climate change. The end-Guadalupian fits this trend.

“I think there’s a problem with hanging on to the number five,” says Richard Bambach, a marine paleoecologist and professor emeritus of paleontology at Virginia Tech who was a reviewer on the landmark Sepkoski-Raup paper. The end-Permian came much closer to wiping out all life when you look at the percentages. But, he says, the end-Guadalupian was astonishingly bad for biodiversity.

“If you actually look at the raw numbers,” he says, “the loss of taxa in the Guadalupian is actually greater than it was in the Permian.”

ESCONI Flashback Friday #33: Plant Life Through The Ages #MazonCreek #paleobotany #paleontology

As part of the celebration of ESCONI's 70th Anniversary, here is Flashback Friday post #33.  If you have pictures or stories to contribute, please send them over to [email protected].  Thanks!

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The "Plant Life Through The Ages" display was created by ESCONI members during the 1950s.  Here is a description from Kathy Dedina, who was president of ESCONI during the 1990s.

"In 1964 Plant Life Through the Ages as exhibited for the first time at the Midwest Federation convention in Muskegon Michigan. Models of early plant life were created by members of the paleontology study group which was formed in 1954. Wilbert Rath directed the project that included lifelike models of plants, the corresponding plant fossils and a reprint of a Vi Sobolik article from the Earth Science magazine. The exhibit covered over 60 feet of space. Later the exhibit was displayed at American Federation and Midwest Federation shows and the Chicago Flower Show. A slide show of the Plant Life was made in 1970."

Here are a few pictures of the exhibit.  It included models, pictures, fossils, and actual plants from throughout the history of life.

Douglas Family Working on Model

Mr Bergen & Nematophyton

Wilbert Rath with Psilophyton

Plant Life with Amphibian

Paleocycas-Early Triassic

Cycad

Williamsonia Jurassic

Neuropteris Gigantea

Pennsylvanian Forest Scene

Plant Life at Muskegon-1964

McLuckie's Alethopteris serlii

 

365-Million-Year-Old Lungfish Unearthed in South Africa

Illustration of Isityumzi mlomomde (lower right) and other Late Devonian freshwater ecosystem creatures including the early tetrapod Unzantsia. Image credit: Maggie Newman.

Sci-News has a story about a recently discovered Lungfish from South Africa.  The new fish, called Isityumzi mlomomde, lived about 365 million years ago during the Devonian period in what is now modern day South Africa.  Lungfish origins stretch back about 410 million years ago to the early Devonian.  Details on this new find can be found in a paper published in the journal PeerJ.

Lungfish (subclass Dipnoi) are a group of lobe-finned fish with their origins stretching back to the Early Devonian period, over 410 million years ago.

They reached a peak of diversity and abundance throughout the Devonian with close to 100 species described from that time period.

More than 25 species originated in the eastern Gondwanan (Australia) waters and others are known to have lived in temperate tropical and subtropical waters of China and Morocco.

The newly-discovered species represents the only record of Late Devonian lungfish remains from the western Gondwana (South America and Africa).

Named Isityumzi mlomomde, the ancient creature is also the only lungfish known from the Witpoort Formation of South Africa.

Merry Christmas! What's a dinosaur's least favorite reindeer?

A 'Jackalope' of an ancient spider fossil deemed a hoax, unmasked as a crayfish #spiders #fossils

The specimen will be stripped of the scientific name Mongolarachne chaoyangensis and rechristened as a crayfish. Credit: Selden et al.

Phys.org has a post about a crayfish masquerading as a spider.  It seems someone painted legs on a poorly preserved crayfish fossil from the Lower Cretaceous Yixian Formation of China.  You can read about their detective work in a paper published in the journal Paleoentomology.

The locals sold the fossil to scientists at the Dalian Natural History Museum in Liaoning, China, who published a description of the fossil species in Acta Geologica Sinica, the peer-reviewed journal of the Geological Society of China. The Chinese team gave the spider the scientific name Mongolarachne chaoyangensis.

But other scientists in Beijing, upon seeing the paper, had suspicions. The spider fossil was huge and strange looking. Concerned, they contacted a U.S. colleague who specializes in ancient spider fossils: Paul Selden, distinguished professor of invertebrate paleontology in the Department of Geology at the University of Kansas.

"I was obviously very skeptical," Selden said. "The paper had very few details, so my colleagues in Beijing borrowed the specimen from the people in the Southern University, and I got to look at it. Immediately, I realized there was something wrong with it—it clearly wasn't a spider. It was missing various parts, had too many segments in its six legs, and huge eyes. I puzzled and puzzled over it until my colleague in Beijing, Chungkun Shih, said, 'Well, you know, there's quite a lot of crayfish in this particular locality. Maybe it's one of those.' So, I realized what happened was I got a very badly preserved crayfish onto which someone had painted on some legs."

Selden and his colleagues at KU and in China (including the lead author of the paper originally describing the fossil) recently published an account of their detective work in the peer-reviewed journal Palaeoentomology.

In Defense of Plants: The Rise and Fall of the Scale Trees #MazonCreek

I recently ran into an interesting post on the blog "In Defense of Plants".  It's called "The Rise and Fall of the Scale Trees".  If you collect or are familiar with Mazon Creek fossils, you probably have heard of Lepidodendron, Stigmaria, Psaronius, Cyperites. etc.  You might even have a few of these fossils.  Some of these are the species name for a plant part or even the name that denotes the whole specimen.  Fossil plants are usually fragmentary and separate parts were given different names.  As more fossils are found, associated parts help paleobotanists assemble whole plants.  This post does a great job explaining what the scale trees were, how they lived, and even how they reproduced.

If I had a time machine, the first place I would visit would be the Carboniferous. Spanning from 358.9 to 298.9 million years ago, this was a strange time in Earth’s history. The continents were jumbled together into two great landmasses - Laurasia to the north and Gondwana to the south and the equatorial regions were dominated by humid, tropical swamps. To explore these swamps would be to explore one of the most alien landscapes this world has ever known.

The Carboniferous was the heyday for early land plants. Giant lycopods, ferns, and horsetails formed the backbone of terrestrial ecosystems. By far the most abundant plants during these times were a group of giant, tree-like lycopsids known as the scale trees. Scale trees collectively make up the extinct genus Lepidodendron and despite constantly being compared to modern day club mosses (Lycopodiopsida), experts believe they were more closely related to the quillworts (Isoetopsida).

World’s Oldest Fossil Forest Unearthed

A Devonian root system at the Cairo fossil forest site. Image credit: Stein et al, doi: 10.1016/j.cub.2019.11.067.

SciNews has a post about the oldest forest ever discovered.  Located in Cairo, NY, near the Devonian fossil forest found near Gilboa, this forest has been dated to about 386 million years old, which is a couple million years older.  Details can be found in a paper which was recently published in the journal Current Biology.

“The Devonian period represents a time in which the first forest appeared on Earth,” said Binghamton University’s Professor William Stein.

“The effects were of first order magnitude, in terms of changes in ecosystems, what happens on the Earth’s surface and oceans, carbon dioxide concentration in the atmosphere, and global climate.”

“So many dramatic changes occurred at that time as a result of those original forests that basically, the world has never been the same since.”

Professor Stein and colleagues found that the Cairo forest was home to at least three unique root systems.

First, they identified a rooting system that they believe belonged to a palm tree-like plant called Eospermatopteris.

PBS Eons: Life, Sex & Death Among the Dire Wolves #paleontology #wolves

 

There's a new episode of PBS's Eons.  It's about wolves and the La Brea Tar Pits in Los Angeles.

This is not a Game of Thrones fan fiction episode. Dire wolves were real! And thousands of them died in the same spot in California. Their remains have taught us volumes about how they lived, hunted, died and way more about any animal’s sex life than you’d ever want to know.

ESCONI Flashback Friday #32: Collecting Mazon Creek Concretions In The 1950s and 1960s #MazonCreek

As part of the celebration of ESCONI's 70th Anniversary, here is Flashback Friday post #32.  If you have pictures or stories to contribute, please send them over to [email protected].  Thanks!

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Enjoy some old photos of the Coal City, Braidwood, and Wilmington area spoil piles in the 1950s and 1960s.  It's too bad some of those are aren't still open for collecting!

Mazon Creek

Strip Mine, Peabody Coal Co.

Fossil nodule on hill

Krup shovel, Peabody Coal Co

Strip area, Coal City, IL

ESCONI lunch, Ceco Club, Coal City, Prepp, Sobolik, H&K Mathies, John & Dick Ade

Nancy at Coal City Club

 

ESCONI January 2020 General Meeting Michelle Wenz - Super Deep Diamonds from Juina, Brazil on January 10, 2020 #gems

Electron microscope images of diamonds from the Juína area of Brazil.Credit...Suzette Timmerman

The speaker at our January 10, 2020 meeting will be Michelle Wenz, a PhD student from Northwestern University. She is working on an suite of superdeep diamonds from Juina, Brazil, many of which appear to have come from the 400-700 km depth range. Her research focus is on water, and deep-mantle water cycling. She developed a method using synchrotron radiation (X-rays) from the Advanced Photon Source at Argonne to image tomographically the location of inclusions inside the diamonds for single-crystal X-ray diffraction, also using the synchrotron X-rays (many of the inclusions are less than 10 micrometers in size, requiring the brilliant X-ray source of the APS). She also recently co-discovered a new rare earth perovskite mineral, which was named goldschmidtite, KNbO3, also found as inclusion in diamond.

43,900-Year-Old Cave Painting Portrays Part-Human, Part-Animal Beings #archaeology

A group of therianthropic figures confronting an anoa at Leang Bulu’ Sipong 4. Image credit: Aubert et al.

SciNews has a story about a very old cave painting discovered in Indonesia.  Archaeologist excavating the limestone cave of Leang Bulu' Sipong 4 on the Indonesian island of Sulawesi discovered a painting that is about 43,900 years old.  The painting depicts a group of 'therianthropes', abstract beings which combine qualities of people and animals, hunting wild pigs and small buffalo-like animals with spears and ropes.  This scene is now the earliest known instance of figurative art in the world.  Details can be found in a recent paper published in the journal Nature.

“The hunters represented in the ancient rock art panel at Leang Bulu’ Sipong 4 are simple figures with human-like bodies, but they have been depicted with heads or other body parts like those from birds, reptiles, and other faunal species endemic to Sulawesi,” said Dr. Adhi Agus Oktaviana, a researcher at Griffith University and the Pusat Penelitian Arkeologi Nasional.

“These therianthropes are portrayed in the act of killing or capturing six fleeing mammals, two Sulawesi warty pigs and four dwarf buffaloes known as anoas. The latter are small but fierce bovids that still inhabit the island’s dwindling forests.”

“Remarkably, some figures appear to be using long ropes to capture these dangerous animals.”

Dr. Oktaviana and colleagues measured the radioactive decay of uranium and other elements within mineral growths that had formed on the cave painting, providing minimum ages ranging from 35,100 to 43,900 years ago for the underlying art.

Ancient 'coal dragon' is now the oldest parareptile ever found #MazonCreek #fossils #Carboniferous

The new species, Carbonodraco lundi, was a lizard-like predator that scampered about an ancient swamps, snatching and stabbing insects and other prey. Its name means 'coal dragon.' (Henry Sharpe/Carleton University)

CBC has a story about an interesting new species of ancient parareptile.  Named Carbonodraco lundi, this animal lived about 306 million years ago in what is now Linton, Ohio.  This is the same time period as the famous fossils from Illinois' Mazon Creek biota.  The details were recently published in the journal Royal Society Open Science.  The paper's lead author is Arjan Mann, a PhD candidate at Carleton University in Ottawa, Ontario, Canada.  You may remember him from some recent posts about Mazon Creek animals in May 2019, June 2019, and August 2019. 

A unique fossil that is "literally a black piece of coal" found in the dump of a 19th-century coal mine is revealing new insights about life before the rise of dinosaurs. It has also unseated a fossil found by a P.E.I. boy as the oldest known species of an ancient group called the "parareptiles."

The new species, Carbonodraco lundi, was a small, lizard-like predator that scampered about in ancient swamps, snatching and stabbing insects and other prey with a sharp pair of fangs.

The animal, which was about 25 centimetres long from nose to tail, lived more than 306 million years ago during the Carboniferous Period in what is now Linton, Ohio, according to a new study by researchers at Carleton University in Ottawa published recently in the journal Royal Society Open Science.

The first part of its name, given by Emily McDaniel, an undergraduate student and co-author of the paper, means "coal dragon," because of the fossil's unique form and its prominent fangs.

Unlike most fossils, which are typically embedded in rocks like shale, limestone or sandstone, this one was "literally a black piece of coal," said Arjan Mann, a PhD candidate at Carleton University and lead author of the report. He said that type of fossil is "very unique."

It was found in the dump of a coal mine operated by the Ohio Diamond Coal Mine Co. by paleontologist Richard Lund of the Carnegie Museum, for whom the species is also named.

New Eocene-Period Whale Unearthed in Egypt #whales #evolution

An artist’s impression of Basilosaurus isis. Image credit: Pavel Riha / CC BY-SA 3.0.

SciNews has a story about a recently discovered whale from the Eocene of Egypt.  Called Aegicetus gehennae, this ancient mammal give important clues in the evolution of whale locomotion.  A team of paleontologists, including Professor Philip Gingerich of the University of Michigan, published the details in a recent paper in the journal PLoS ONE.

Protocetidae (protocetids) are a group of semi-aquatic whales known from the middle Eocene epoch of Africa, Asia, North America, and South America.

While living whales use their tails to propel themselves through the water, most protocetids were foot-powered swimmers.

The newly-discovered protocetid, Aegicetus gehennae, was more fully aquatic and less specialized as a foot-powered swimmer than earlier protocetids.

It represents a transitional stage between the foot-powered swimming of early whales and the tail-powered swimming of living whales.

“It is the youngest-known protocetid, dating to around 35 million years ago, and is known from one exceptionally complete skeleton and a partial second specimen, making it among the best-preserved ancient whales,” explained University of Michigan’s Professor Philip Gingerich and colleagues.

Aegicetus gehennae had an estimated body mass of about 900 kg, according to the team.

“Compared with earlier whales, it has a more elongated body and tail, smaller back legs, and lacks a firm connection between the hind legs and the spinal column,” the researchers said.

Roy Plotnick: Existence Locates a Path #paleontology #geology #massextinction #extinction

Comic courtesy of Nathan Pyle, author of Strange Planet

Roy Plotnick has a new post over on Medium.  The post is about extinction... mass extinction.  We have a roll in the current and a past extinction.  Time for action!

Mass extinctions and their causes are topics of intense interest. Nearly forty years after the 1980 paper on the end-Cretaceous impact, significant new research on it and on the resulting extinction continue to appear. Other mass extinctions, such as the ones at the end of the Ordovician and Permian, likewise are fertile areas for investigation. But what has become of equal interest to paleontologists is the aftermath of these cataclysmic episodes: how does life recover after extinctions and how does the rebuilding biosphere differ from what went before? Four very different recent papers show the paths that life took after the Cretaceous-Paleocene (K-Pg) extinction event. Together, they are a warning to us.

PBS Eons: The Forgotten Story of the Beardogs #paleontology

 

PBS Eons has a new eposide and it's about Beardogs, otherwise known as Amphicyonids.

Because of their strange combination of bear-like and dog-like traits, they’re sometimes confusingly called the beardogs. And even though you’ve never met one of these animals, the beardogs are key to understanding the history of an important branch of the mammal family tree.

ESCONI Flashback Friday #31: Andy Hay Memorial Scholarship #MazonCreek

As part of the celebration of ESCONI's 70th Anniversary, here is Flashback Friday post #31.  If you have pictures or stories to contribute, please send them over to [email protected].  Thanks!

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Andy Hay was a long time ESCONI member.  He joined in 1976 and was a member to the very end.  He wrote the Creature Corner column in the ESCONI bulletin for many years.  He was heavily involved in the creation of "Keys To Identify Pennsylvanian Fossil Animals of the Mazon Creek Area", which was first published in 1989.  This was the definitive guide for a long time.  He was heavily involved in the Paleontology Study Group for many years.  Additionally, he was instrumental in the "Mazon Creek Project" and because of his efforts we can collect at Pit 11 even today!

I never met him, but from the stories, I sure wish I did!

Andy Hay Memorial Scholarship

From the Northeastern Illinois University Newsletter for NEIU Donors February 2004

Friends and family of Andrew A. Hay, distinguished university fellow in the earth science department, recently established the Andrew A. Hay Memorial Scholarship fund. The earth science department will award the scholarship. It will be open to earth science majors who have a grade point average of 3.0 and higher.

Mr. Hay passed away on November 1, 2003. He was well known at Northeastern for his work on the Mazon Creek Project, his dedication to the earth science department and inspiring personality. As one professor wrote: “Mr. Hay was a strong presence in our department. When I saw him in action in the morning, the United States Army slogan comes to mind, that' ...(he did) more before 9:00 a.m. than most people do all day.' His attention to detail, positive attitude and strong work ethic make him an invaluable asset to the Mazon Creek Project and to the department of earth science". He will be missed by everyone who knew him.

If you are interested in making a gift in support of the scholarship, make your check payable to the NEIU Foundation and mail to Northeastern Illinois University Foundation, 5500 N. St. Louis Ave. Chicago, IL 60625

And from the February, 2004 Esconi Earth Science News...

Andrew A. Hay Memorial Scholarship Northeastern Illinois University

The HAY Family has established this scholarship and hop to award it for the first time this spring. It will honor the life and passion for geology of Andy Hay and will be awarded to an earth science major or minor that meets its scholastic requirements. Preference will be given to members or relatives of members of ESCONI, the Des Plaines Valley Geological Society or the Chicagoland Gem and Mineral Society.

The University Foundation contact is Collette Borland, Assistant Director, Development. The address is 5500 N St. Louis Avenue, Chicago, IL 60625-4969

Earth was stressed before dinosaur extinction #dinosaurs #massextinction

Ben Linzmeier holds a fossilized clam shell found while trekking through the Lopez de Bertodano Formation, a well-preserved, fossil-rich area on the west side of Seymour Island in Antarctica. Credit: Northwestern University

Phys.org has an interesting story about the extinction of the dinosaurs.  A new study, led by researchers from Northwestern University, shows that the chemistry of fossilized clam and snail shells changed greatly in the years leading up to the K-Pg mass extinction event.  This change is likely due to a large influx of carbon into the oceans which was caused by the long-term volcanic eruptions that formed the Deccan Traps.  The Deccan Traps are a 200,000 square mile volcanic province located in modern day India.  Find all the detail in a paper published in the journal Geology.

New evidence gleaned from Antarctic seashells confirms that Earth was already unstable before the asteroid impact that wiped out the dinosaurs.

The study, led by researchers at Northwestern University, is the first to measure the calcium isotope composition of fossilized clam and snail shells, which date back to the Cretaceous-Paleogene mass extinction event. The researchers found that—in the run-up to the extinction event—the shells' chemistry shifted in response to a surge of carbon in the oceans.

This carbon influx was likely due to long-term eruptions from the Deccan Traps, a 200,000-square-mile volcanic province located in modern India. During the years leading up to the asteroid impact, the Deccan Traps spewed massive amounts of carbon dioxide (CO2) into the atmosphere. The concentration of CO2 acidified the oceans, directly affecting the organisms living there.

"Our data suggest that the environment was changing before the asteroid impact," said Benjamin Linzmeier, the study's first author. "Those changes appear to correlate with the eruption of the Deccan Traps."

"The Earth was clearly under stress before the major mass extinction event," said Andrew D. Jacobson, a senior author of the paper. "The asteroid impact coincides with pre-existing carbon cycle instability. But that doesn't mean we have answers to what actually caused the extinction."