The overwhelming majority of previous climate-change studies on the 400,000-year transition from the Eocene to the Oligocene epochs, about 33.5 million years ago, focus on marine environments, but University of Florida vertebrate paleontologist Bruce MacFadden and his colleagues turned their attention to fossils from the Great Plains.
The study will be published online Feb. 7 in the journal Nature and will appear in the Feb. 8 print edition.
"If a temperature change of this magnitude occurred today, Florida would have weather similar to Washington, D.C., or even farther north," said MacFadden, a curator at the Florida Museum of Natural History.
The Eocene-to-Oligocene transition is known in the fossil record as the Grande Coupure, the "Big Cut" in French, because it marks a massive extinction of life in both marine and land environments. Scientists believe the drop in temperature was likely due to changes in oceanic currents, MacFadden said.
"Fossil mammals are archives of ancient information," MacFadden said. "Their teeth are like little time capsules that allow us to analyze chemicals captured millions of years ago within the animals' skeletons."
MacFadden said 49 of the 68 fossil teeth analyzed came from the Florida Museum's vertebrate paleontology collection. Researchers analyzed oxygen and carbon isotopes in the preserved teeth and bones of primitive fossil horses and a primitive cloven-hoofed mammal called an oreodont. Isotopes are atoms of naturally occurring elements, characterized by varying numbers of neutrons but constant numbers of protons. Oxygen isotopes act as thermometers, telling scientists at what temperature they were formed; and carbon isotopes act as barometers, revealing relative humidity.
"A combined analysis of the isotope composition of bones and teeth is a new approach to studying this boundary in time," said Alessandro Zanazzi, a doctoral student in geology at the University of South Carolina and lead author of the paper. "Tooth enamel has very low porosity and low organic matter, so it maintains the isotopic composition of when it was formed."
Donald R. Prothero, a professor of geology at Occidental College and an expert on the Eocene-to-Oligocene transition, said, "We have long known that there were some dramatic climatic changes in the earliest Oligocene based on the record of marine plankton and isotopes. But we didn't know how much change there was in degrees, although the plant changes suggested it was indeed about 15 degrees."
Prothero also said gaps in the fossil record from Nebraska may have prevented researchers from obtaining detailed temperature data, and he hopes further studies will be completed at other sites such as Wyoming.
Bruce MacFadden | EurekAlert!
Study relating to materials testing Detecting damages in non-magnetic steel through magnetism
23.07.2018 | Technische Universität Kaiserslautern
Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
17.08.2018 | Physics and Astronomy
17.08.2018 | Information Technology
17.08.2018 | Life Sciences