Few specimens inspire greater thrills among fossil collectors than a complete trilobite. These ancient arthropods – relatives of lobsters, spiders and insects – went extinct more than 250 million years ago, but are sometimes found in beautifully preserved condition.
In rare instances, an entire population of trilobites is found fossilized together. Carlton E. Brett finds evidence for ancient environment and behavior in these mass graves.Brett, University of Cincinnati professor of geology, will present his findings March 20 at the Geological Society of America regional meeting in Pittsburgh, in a paper co-authored with Adrian Kin of Poland’s Institute of Geological Sciences at Jagiellonian University, and Brenda Hunda of the Cincinnati Museum Center.
In a quest that has taken him from Oklahoma to Morocco and Poland, Brett has analyzed multiple examples of mass trilobite burial. A smothering death by tons of hurricane-generated storm sediment was so rapid that the trilobites are preserved in life position. These geologic “snapshots” record behavior in much the way that ancient Roman life was recorded at Pompeii by volcanic ash.Burial was rapid, Brett said, but also somewhat delicate. Trilobites, like other arthropods, shed their hard exoskeletons from time to time.
“We find molted pieces lying immediately adjacent to each other,” he said. “This is proof that the sediments were not significantly disturbed after burial.”
Like modern crabs and lobsters, trilobites appear to have gathered in large groups for protection when they shed their protective exoskeletons. During molting, there was safety in numbers. And, like their modern cousins, trilobites seem to have used these molting gatherings as opportunities for mating.
The mass burials preserve large groups of similar-sized – and therefore similarly aged – specimens, segregated by species and, after molting, “naked.”
“It’s an orgy,” Brett said.
Brett and colleagues found evidence of another behavioral connection to modern arthropods – long chains of trilobites apparently fossilized in mid-migration.
“The recent discovery of rows of more than a dozen specimens provides the oldest evidence of migratory queues similar to those seen in modern crustaceans,” Brett said.
Taken together, the mass burials record an array of communal behaviors in ancient trilobites, comparable to those seen in some living crustaceans.
“Such evidence points to complex synchronized escape and reproductive behavior,” Brett said. “This provides extraordinary insights into the paleobiology of these ancient organisms.”
UC's paleontology program was again ranked sixth in the nation by U.S. News on March 15, 2011.
Greg Hand | EurekAlert!
Stagnation in the South Pacific Explains Natural CO2 Fluctuations
23.02.2018 | Carl von Ossietzky-Universität Oldenburg
First evidence of surprising ocean warming around Galápagos corals
22.02.2018 | University of Arizona
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy