Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Reverse evolution in real-time

Instituto Gulbenkian de Ciência scientists turn back clock on evolution in fruit fly to provide key insights into basic mechanisms of evolution

In his book, Wonderful World, Stephen Jay Gould writes about an experiment of ‘replaying life’s tape’, wherein one could go back in time, let the tape of life play again and see if ‘the repetition looks at all like the original’.

Evolutionary biology tells us that it wouldn’t look the same – the outcome of evolution is contingent on everything that came before. Now, scientists at the Instituto Gulbenkian de Ciência (IGC) in Portugal, New York University and the University of California Irvine, provide the first quantitative genetic evidence of why this is so.

In this study, to be published online this week in the journal Nature Genetics, Henrique Teotónio and his colleagues recreated natural selection in real-time, in the laboratory (rather than based on inferences from fossil records or from comparing existing natural populations) and provide the first quantitative evidence for natural selection on so-called standing genetic variation – a process long thought to be operating in natural populations that reproduce sexually but which, until now, had never been demonstrated.

The researchers used laboratory-grown populations of fruit fly (Drosophila melanogaster), derived from an original group of flies, harvested from the wild back in 1975. These ancestral flies were grown in the laboratory, for two decades, under different environmental conditions, (such as starvation and longer life-cycles) so that each population was selected for specific characteristics. Henrique Teotónio and his colleagues placed these populations back in the ancestral environment, for 50 generations, to impose reverse evolution on the flies, and then looked at the genetic changes in certain areas of chromosome 3 of these flies.

Says Henrique, ‘In 2001 we showed that evolution is reversible in as far as phenotypes are concerned, but even then, only to a point. Indeed, not all the characteristics evolved back to the ancestral state. Furthermore, some characteristics reverse-evolved rapidly, while others took longer. Reverse evolution seems to stop when the populations of flies achieve adaptation to the ancestral environment, which may not coincide with the ancestral state. In this study, we have shown that underlying these phenomena is the fact that, at the genetic level, convergence to the ancestral state is on the order of 50%, that is, on average, only half of the gene frequencies revert to the ancestral gene frequencies – evolution is contingent upon history at the genetic level too’.

These findings provide further insights into the basic understanding of how evolution and diversity are generated and maintained. On the one hand, it provides evidence for evolution happening through changes in the distribution of alleles in a population (so-called standing genetic variation), from generation to generation, rather than the appearance of mutations, from one generation to the next. On the other hand, as Henrique notes, ‘It has implications for the definition of biodiversity: some of the ‘reversed’ flies may be phenotypically identical to the ancestral flies, but they are genetically different. How then do we define biodiversity?’

This study was funded by a Fundação para a Ciência e a Tecnologia grant awarded to Henrique Teotónio, who joined the IGC in 2003 as a group leader and currently heads the Evolutionary Genetics group and the in-house PhD Programme in Life Sciences.

Ana Godinho | alfa
Further information:

More articles from Life Sciences:

nachricht Gene therapy shows promise for treating Niemann-Pick disease type C1
27.10.2016 | NIH/National Human Genome Research Institute

nachricht 'Neighbor maps' reveal the genome's 3-D shape
27.10.2016 | International School of Advanced Studies (SISSA)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

How nanoscience will improve our health and lives in the coming years

27.10.2016 | Materials Sciences

OU-led team discovers rare, newborn tri-star system using ALMA

27.10.2016 | Physics and Astronomy

'Neighbor maps' reveal the genome's 3-D shape

27.10.2016 | Life Sciences

More VideoLinks >>>