Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

In Evolution Game, Survival Doesn’t Equal Success

11.06.2002


Finding has implications for future of biodiversity



A significant number of organisms that survived the five greatest mass extinctions in Earth’s history subsequently failed to achieve evolutionary success, according to a new study funded by the National Science Foundation (NSF) and conducted by University of Chicago scientist David Jablonski.

"It’s clear that there is a lot of evolutionary action in the aftermath of mass extinctions," said Jablonski. "During the rebound from mass extinctions, it’s not an all-or-nothing thing. The shape of the post-extinction world comes not only from who goes extinct, but from which survivors are successful - or, instead, become extinct or marginalized in the aftermath."


Jablonski lays out his evidence in the June 11 issue of the journal, Proceedings of the National Academy of Sciences. The research was also supported by the Guggenheim Foundation.

"Because most extinction event survivor organisms rebound so robustly, paleontological studies are generally focused on these evolutionary winners," explains Richard Lane, director of NSF’s paleontology program. "Jablonski’s research examines why other groups of organisms weakly struggle through these major catastrophic events only to meet their demise somewhat later, geologically speaking."

To test the idea that many survivors go on to lose the evolutionary game, Jablonski turned to the paleontological literature and to his own work on the aftermath of mass extinction at the end of the Mesozoic Era. In a global analysis of marine genera, he determined how many lineages survived each of the largest mass extinctions in Earth’s history only to die off within the first five or 10 million years thereafter.

Patterns at higher levels of biological organization - for example, orders that include a large number of genera - often play out differently. However, Jablonski also found a 17 percent extinction rate for orders following three of the five big mass extinctions.

This result surprised Jablonski, who had assumed that survival of a mass extinction would be good news for most major groups. "It wasn’t good news for everybody, even at this level," he said.

These sets of doomed survivors are the last representatives of their clades, a technical term for an evolutionary group of organisms that includes an ancestor and all of its descendants. Jablonski creates a special category for them in his article, calling them "Dead Clade Walking," in homage to the 1995 film "Dead Man Walking," about a death-row inmate.

Paleontologists still poorly understand the process that sorts the winners from the losers after a major extinction, Jablonski said. His statistical analysis ruled out one of the most straightforward of possible causes - that lineages that have suffered a major blow to their numbers during a mass extinction might be especially extinction-prone in the aftermath because they contain fewer species to buffer against the hard times. Instead, Jablonski found that many of the biggest post-extinction winners had passed through a diversity bottleneck as narrow as the Dead Clade Walking groups.

Other possible causes include environmental change and increased competition between species. Both issues need further study, Jablonksi said, and there are probably examples of each in the fossil record.

Cheryl Dybas | National Science Foundation

More articles from Life Sciences:

nachricht Russian scientists show changes in the erythrocyte nanostructure under stress
22.02.2019 | Lobachevsky University

nachricht How the intestinal fungus Candida albicans shapes our immune system
22.02.2019 | Exzellenzcluster Präzisionsmedizin für chronische Entzündungserkrankungen

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: (Re)solving the jet/cocoon riddle of a gravitational wave event

An international research team including astronomers from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has combined radio telescopes from five continents to prove the existence of a narrow stream of material, a so-called jet, emerging from the only gravitational wave event involving two neutron stars observed so far. With its high sensitivity and excellent performance, the 100-m radio telescope in Effelsberg played an important role in the observations.

In August 2017, two neutron stars were observed colliding, producing gravitational waves that were detected by the American LIGO and European Virgo detectors....

Im Focus: Light from a roll – hybrid OLED creates innovative and functional luminous surfaces

Up to now, OLEDs have been used exclusively as a novel lighting technology for use in luminaires and lamps. However, flexible organic technology can offer much more: as an active lighting surface, it can be combined with a wide variety of materials, not just to modify but to revolutionize the functionality and design of countless existing products. To exemplify this, the Fraunhofer FEP together with the company EMDE development of light GmbH will be presenting hybrid flexible OLEDs integrated into textile designs within the EU-funded project PI-SCALE for the first time at LOPEC (March 19-21, 2019 in Munich, Germany) as examples of some of the many possible applications.

The Fraunhofer FEP, a provider of research and development services in the field of organic electronics, has long been involved in the development of...

Im Focus: Regensburg physicists watch electron transfer in a single molecule

For the first time, an international team of scientists based in Regensburg, Germany, has recorded the orbitals of single molecules in different charge states in a novel type of microscopy. The research findings are published under the title “Mapping orbital changes upon electron transfer with tunneling microscopy on insulators” in the prestigious journal “Nature”.

The building blocks of matter surrounding us are atoms and molecules. The properties of that matter, however, are often not set by these building blocks...

Im Focus: University of Konstanz gains new insights into the recent development of the human immune system

Scientists at the University of Konstanz identify fierce competition between the human immune system and bacterial pathogens

Cell biologists from the University of Konstanz shed light on a recent evolutionary process in the human immune system and publish their findings in the...

Im Focus: Transformation through Light

Laser physicists have taken snapshots of carbon molecules C₆₀ showing how they transform in intense infrared light

When carbon molecules C₆₀ are exposed to an intense infrared light, they change their ball-like structure to a more elongated version. This has now been...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Global Legal Hackathon at HAW Hamburg

11.02.2019 | Event News

The world of quantum chemistry meets in Heidelberg

30.01.2019 | Event News

Our digital society in 2040

16.01.2019 | Event News

 
Latest News

JILA researchers make coldest quantum gas of molecules

22.02.2019 | Physics and Astronomy

Understanding high efficiency of deep ultraviolet LEDs

22.02.2019 | Materials Sciences

Russian scientists show changes in the erythrocyte nanostructure under stress

22.02.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>