Around 540 million years ago there was a sudden diversification of species on earth. Within a short period of time, countless new species evolved almost simultaneously, becoming the predecessors of today's main animal groups. But what caused this rapid evolution? Palaeontologists around the world have been searching for the answer to this question for centuries.
Researchers at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have now confirmed the existing theories that extreme niche formation and tectonic plate movements are responsible for the development of the wide variety of species. Their findings have recently been published in the renowned journal PNAS*.
451 million years ago, an event took place that had a major influence on the evolution of life on earth. This event was the Cambrian explosion, which took place at the beginning of the Cambrian Period over a – from a geological point of view – relatively short period of 5 to 10 million years and saw the evolution of all of the major modern animal groups.
To find out what caused this event, researchers from FAU's Geozentrum Nordbayern evaluated a large database of fossils from the Cambrian Period. They analysed the biological diversity of all known species from this period on a local, regional and global level with the aim of understanding the ecological principles that led to the Cambrian explosion.
The causes? Niche formation and plate tectonics
'We discovered that while the number of species within local ecosystems increased in the early Cambrian Period, this was not the main reason for the evolution of the variety of species on a global level,' says Lin Na from FAU's Chair of Palaeoenvironmental Studies. Instead, the different evolution of different populations was much more important.
This is because as species adapted more and more to their environment their ecological niches became more restricted. This meant that individual populations evolved into new species that were adapted to their environments. Carnivores played an important role in this, as Prof. Dr. Wolfgang Kießling, Chair of Palaeoenvironmental Studies, explains.
'Carnivores kept populations small, preventing too much competition for resources. At the same time, however, they forced species to develop new ways of avoiding being eaten and increasingly sophisticated methods of getting food.'
This biological arms race controlled the variety of species at a local and regional level. However, on a global level there was another factor driving the evolution of species forward: plate tectonics. At the beginning of the Cambrian Period, the supercontinent Pannotia broke apart. From then on, deep oceans separated parts of the land and the different sea creatures evolved separately.
'We saw a significant increase in provincialism. The species composition found in the continents' different old shelf seas became more and more different. This could be the main reason that the total number of species increased so considerably,' says Lin Na.
*Lin Na, Wolfgang Kießling: 'Diversity partitioning during the Cambrian radiation', Proceedings of the National Academy of Sciences (USA). doi: 10.1073/pnas.1424985112
Prof. Dr. Wolfgang Kießling
Phone: +49 9131 8526959
Dr. Susanne Langer | idw - Informationsdienst Wissenschaft
Climate change weakens Walker circulation
20.10.2017 | MARUM - Zentrum für Marine Umweltwissenschaften an der Universität Bremen
Shallow soils promote savannas in South America
20.10.2017 | Senckenberg Forschungsinstitut und Naturmuseen
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research