An international team of researchers has used the power of genomics to reveal the mechanisms of an ancient and ongoing arms-race between butterflies and plants, played out in countless gardens around the world as green caterpillars devour cabbage plants.
This study appears 50 years after a classic paper by Drs. Paul Ehrlich and Peter Raven that formally introduced the concept of coevolution using butterflies and plants as primary examples. The present study not only provides striking support for coevolution, but also provides fundamentally new insights into its genetic basis in both groups of organisms. (Proceedings of the National Academy of Sciences of the USA, June 2015).
Larva of the Black Jezebel butterfly (Delias nigrina) feeding on mistletoes. This species has lost the ability to feed on cabbage plants.
Heiko Vogel / Max Planck Institute for Chemical Ecology
The major chemical defense of cabbage plants and relatives belonging to the mustard family Brassicales is based on a two-component activated system composed of non-toxic precursors (the glucosinolates or mustard oils) and plant enzymes (myrosinases). These are spatially separated in healthy tissue, but when the tissue is damaged by chewing insects both components are mixed and the so-called "mustard oil bomb" is ignited, producing a series of toxic breakdown products.
It is exactly these breakdown products that can be appealing to humans in certain concentrations (as found in mustard) as well as deterrent or toxic to unadapted herbivores. However, some insects have specialized on cabbage plants and have found various ways to cope with their host plant defenses. Among these are pierids (the White butterflies) and relatives, which specialized on these new host plants shortly after the evolutionary appearance of the Brassicales and their “invention” of the glucosinolate-based chemical defense.
Comparing the evolutionary histories of these plants and butterflies side-by-side, the researchers discovered that major advances in the chemical defenses of the plants were followed by butterflies evolving counter-tactics that allowed them to keep eating these plants. This back-and-forth dynamic was repeated over nearly 80 million years, resulting in the formation of more new species, compared to other groups of plants without glucosinolates and their herbivores.
Thus, the successful adaptation to glucosinolates enabled this butterfly family to rapidly diversify; and pierids are nowadays widespread with some species being very abundant worldwide, such as the Small White and the Large White. While most butterflies of this family now feed on Brassicales, some relatives stick with the ancestral preference for legumes and cannot detoxify glucosinolates. Secondary host shifts away from Brassicales have also taken place, with some species now feeding on other host plants such as mistletoes.
By sequencing the genomes of both plants and butterflies, the researchers discovered the genetic basis for this arms race. Advances on both sides were driven by the appearance of new copies of genes, rather than by simple point mutations in the plants’ and butterflies’ DNA.
Furthermore butterfly species that first developed gene copies adapted to glucosinolates, but later shifted to feeding on non-Brassicales plants such as mistletoes, showed a different pattern. The genes responsible for the ‘mustard-adaptations’ have completely vanished from their genomes. Even an adaptation that took 80 million years to evolve can be discarded when it is no longer needed.
The research is the product of an international team of plant scientists from the University of Missouri, USA and butterfly biologists from Stockholm University, Sweden and the Max Planck Institute for Chemical Ecology, Germany.
Edger, P.P., Heidel-Fischer, H. M., Bekaert, M., Rota, J., Glöckner, G., Platts, A. E., Heckel, D. G., Der, J. P., Wafula, E. K., Tang, M., Hofberger, J. A., Smithson, A., Hall, J. C., Blanchette, M., Bureau, T. E., Wright, S. I., dePamphilis, C. W., Schranz, M. E., Barker, M. S., Conant, G. C., Wahlberg, N., Vogel, H., Pires, J. C., Wheat, C. W. (2015). The butterfly plant arms-race escalated by gene and genome duplications. Proceedings of the National Academy of Sciences of the USA.
Dr. Hanna Heidel-Fischer, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany, Tel. +49 3641 57-1516, E-Mail email@example.com
Dr. Heiko Vogel, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany, Tel. +49 3641 57-1512, E-Mail firstname.lastname@example.org
Contact and Picture Requests:
Angela Overmeyer M.A., Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07743 Jena, Germany, +49 3641 57-2110, E-Mail email@example.com
Download of high resolution images via http://www.ice.mpg.de/ext/downloads2015.html
Angela Overmeyer | Max-Planck-Institut für chemische Ökologie
New 3-D model predicts best planting practices for farmers
26.06.2017 | Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign
Fighting a destructive crop disease with mathematics
21.06.2017 | University of Cambridge
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine
Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...
19.06.2017 | Event News
13.06.2017 | Event News
13.06.2017 | Event News
26.06.2017 | Life Sciences
26.06.2017 | Physics and Astronomy
26.06.2017 | Information Technology