Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Visiting researcher at Kassel University solves riddle of Cambrian fossils

01.08.2017

Three fossils from the Early Cambrian which have long posed a puzzle to scientists belong to the same primeval creature. This has been shown in studies of new finds from the so-called Chengjiang deposits dating back to more than 500 million years ago. Paleontologist Dr. Qiang Ou, a guest researcher working together with Prof. Dr. Georg Mayer at the University of Kassel, played a significant role in the new discovery. These findings provide new insights regarding the evolution of the diversity of species during the so-called Cambrian explosion.

Based on the findings of Ou, Mayer, and additional co-authors of the study, the primeval creature †Xianguangia sinica, which lived approximately 520 million years ago, was an ancestral cnidarian, contrary to what was previously believed. The cnidarians today include jellyfish, corals, and sea anemones.


Reconstruction of the feather polyp †Xianguangia sinica, an extinct representative of the cnidarian stem group.

Copyright: Huanzhen Li & Qiang Ou

The animal measured approximately five centimetres in height and resembled a polyp, but possessed an additional body cavity that apparently served as a hydrostatic skeleton within an anchoring device at the base of the body. Feather-like tentacles with numerous cilia were characteristic for the species and served for capturing food particles from the water column.

“The ‘feather polyp’,” as the scientists informally named †X. sinica, “was a so-called suspension feeder,” says Mayer. This means that it filtered organic particles from the surrounding water through the action of cilia that transported food material towards the mouth. This finding refutes previous hypothesis that †X. sinica was a predator which, like most living cnidarians, caught macroscopic planktonic organisms using simple, unbranched tentacles laden with venomous cnidocytes.

The scientists have now been able to clarify the contradictory classification of the fossils †Chengjiangopenna wangii (a purported Cambrian “sea pen”) and †Galeaplumosus abilus (the “oldest hemichordate”). It now has become evident that these fossils are simply body fragments of †X. sinica. Previously, they had been incorrectly identified and described as separate species.

The detailed reconstruction of the body structure of †X. sinica was made possible by examining 85 new and exceptionally preserved specimens from the Chengjiang deposit in China. Ou, Mayer, and their colleagues examined these specimens using scanning electron microscopy (SEM) as well as energy-dispersive X-ray spectroscopy (EDX). In addition, the researchers conducted phylogenetic analyses in order to clarify the position of the fossil species in the animal tree of life. The results indicate that the diversity of cnidarian morphology and feeding behaviour was higher in the Cambrian than previously thought.

Major parts of this study were carried out at the University of Kassel where Dr. Qiang Ou (40) is conducting research as an Alexander von Humboldt Fellow in the Zoology department.

In the last decades, numerous previously unknown fossils have been discovered in the Chengjiang deposits, opening up new dimensions in our understanding of biodiversity in the Cambrian period. Many of these fossils, however, have not yet been completely and unequivocally analysed. The term "Cambrian explosion" refers to a massive emergence of new species during the Cambrian period approximately 530 million years ago.

The new results concerning the species †Xianguangia sinica have been published in the prestigious journal "Proceedings of the National Academy of Sciences of the United States of America": http://www.pnas.org/content/early/2017/07/26/1701650114.abstract

Contact details:
Prof. Dr. Georg Mayer
University of Kassel
Department of Zoology
Phone: +49 (0)561 804-4805
E-Mail: georg.mayer@uni-kassel.de

Weitere Informationen:

http://www.uni-kassel.de/uni/universitaet/pressekommunikation/neues-vom-campus/m...
http://www.pnas.org/content/early/2017/07/26/1701650114.abstract

Sebastian Mense | idw - Informationsdienst Wissenschaft

More articles from Earth Sciences:

nachricht Hundreds of bubble streams link biology, seismology off Washington's coast
22.03.2019 | University of Washington

nachricht Atmospheric scientists reveal the effect of sea-ice loss on Arctic warming
11.03.2019 | Institute of Atmospheric Physics, Chinese Academy of Sciences

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Important Progress in the Fight against Testicular Cancer

25.03.2019 | Life Sciences

Measurement of thoughts during knowledge acquisition

25.03.2019 | Life Sciences

Eliminating hepatitis C viruses effectively

25.03.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>