Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists move a step closer to linking embryos of earth’s first animals to adult form

03.11.2004


Animal embryos


In 1998, Shuhai Xiao and colleagues reported finding thousands of 600 million year old embryo microfossils in the Neoproterozoic Doushantuo Formation, a fossil site near Weng’an, South China, (Xiao, S., Zhang, Y., and Knoll, A.H., 1998, "Three-dimensional preservation of algae and animal embryos in a Neoproterozoic phosphorite," Nature, v. 391). Within the egg cases they examined at that time, they discovered animals in the first stages of development – from a single cell to only a few dozen cells. "The cellular preservation is amazing," says Xiao, assistant professor of geosciences at Virginia Tech.

But what kind of adult would these ancient embryos have hatched into?

In 2000, Xiao’s team reported the discovery of a coral-like animal that might be a candidate for parenthood (Xiao, S., Yuan, X., and Knoll, A.H., 2000, "Eumetazoan fossils in terminal Proterozoic phosphorites?" Proceedings of the National Academy of Sciences, USA, v. 97). "It was tubular, not spherical. But in some of the best specimens, we could see that the tube branches and has cross-walls," Xiao said. "But can it be linked to the embryos?"



Upon examination of more embryos collected from the original site, Xiao’s research team has discovered some embryos that may be at the hatching stage. He will report on this latest finding at the Geological Society of America meeting in Denver Nov. 7-10. "Looking now at these egg cases, we can see clockwise spiral grooves, as if a knife sliced the egg open," Xiao said. "The embryo was beginning to hatch. When we removed the egg case, we found that the post blastula but pre-hatching embryo at this stage is beginning to transform into a spiral animal. Each such animal had three clockwise spires. After hatching, the spiral organism began to uncoil slightly," Xiao said. "They look as if they can unwind to a tube structure. We are looking for more evidence, but if that is true, it might link the embryo fossils to the tubular coral-like animal."

The researchers will slice open a hatched embryo specimen that appears to be unwinding to see if it has cross-walls. "That would indicate it is related to the tubes," Xiao said. "These organisms lived 600 million years ago – before big animals. This the very first moment of animal evolution preserved in the fossil record."

The research, "Animal Embryos from the terminal Neoproterozoic Doushantuo Formation: How did they hatch?," written by Xiao of Virginia Tech’s College of Science, and Chuanming Zhou and Xunlai of the Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences, will be presented at 1:30 p.m. Wednesday, Nov. 10, in rooms 108/110/112 of the Colorado Convention Center.

Susan Trulove | EurekAlert!
Further information:
http://www.vt.edu

More articles from Earth Sciences:

nachricht New research calculates capacity of North American forests to sequester carbon
16.07.2018 | University of California - Santa Cruz

nachricht Scientists discover Earth's youngest banded iron formation in western China
12.07.2018 | University of Alberta

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>