The problem highlights a general issue in evolutionary biology of what determines the range of plants and animals we see compared to those that might have evolved theoretically. To what extent does observed biodiversity reflect the rules of development or the action of Darwinian selection?
To address this problem, Enrico Coen at the John Innes Centre and Dr. Przemyslaw Prusinkiewicz and colleagues at the University of Calgary analysed not Unicorns, but a more tractable system, the evolution of flower branching displays, or inflorescences. Flowering plants have three basic types of inflorescence - racemes, cymes and panicles. Theoretically there are many other possible branching arrangements so why has nature chosen only these three? The researchers showed how the three types arise quite naturally from a simple mathematical model for how growing tips switch to make flowers. The model was supported by experimental studies on genes in the garden weed Arabidopsis.
So it looks like the way genes control development plays an important role in determining what sorts of structure evolve. But the researchers also showed that selection plays a key part in setting the routes that evolution may take within the space of possibilities. They revealed novel paths, called evolutionary wormholes that link together different inflorescence types, allowing one to evolve into another. Perhaps there are no Unicorns because no evolutionary wormholes exist that connect them to horses, or maybe the wormholes are there but evolution has not had time to go down them. The riddle of the Unicorn remains but at least scientists now have a more rigorous mathematical and experimental framework in which to consider such issues.
Antimicrobial substances identified in Komodo dragon blood
23.02.2017 | American Chemical Society
New Mechanisms of Gene Inactivation may prevent Aging and Cancer
23.02.2017 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
23.02.2017 | Physics and Astronomy
23.02.2017 | Earth Sciences
23.02.2017 | Life Sciences