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 firstname.lastname@example.org
Dr. Heiko Vogel, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany, Tel. +49 3641 57-1512, E-Mail email@example.com
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 firstname.lastname@example.org
Download of high resolution images via http://www.ice.mpg.de/ext/downloads2015.html
Angela Overmeyer | Max-Planck-Institut für chemische Ökologie
Alkaline soil, sensible sensor
03.08.2017 | American Society of Agronomy
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
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
21.08.2017 | Materials Sciences
21.08.2017 | Health and Medicine
21.08.2017 | Materials Sciences