Arthropod-Plant Interactions

, Volume 4, Issue 1, pp 1–6 | Cite as

Why do many galls have conspicuous colors? A new hypothesis

  • M. InbarEmail author
  • I. Izhaki
  • A. Koplovich
  • I. Lupo
  • N. Silanikove
  • T. Glasser
  • Y. Gerchman
  • A. Perevolotsky
  • S. Lev-Yadun
Forum Paper


Galls are abnormal plant growth induced by various parasitic organisms, mainly insects. They serve as “incubators” for the developing insects in which they gain nutrition and protection from both abiotic factors and natural enemies. Galls are typically armed with high levels of defensive secondary metabolites. Conspicuousness by color, size and shape is a common gall trait. Many galls are colorful (red, yellow etc.) and therefore can be clearly distinguished from the surrounding host plant organs. Here we outlined a new hypothesis, suggesting that chemically protected galls which are also conspicuous are aposematic. We discuss predictions, alternative hypotheses and experimental tests of this hypothesis.


Aposematism Chemical defense Extended phenotype Plant manipulation Warning coloration 



We thank Martin Schaefer, Stig Larsson and anonymous referees for their critical suggestions and comments.


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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • M. Inbar
    • 1
    Email author
  • I. Izhaki
    • 1
  • A. Koplovich
    • 1
  • I. Lupo
    • 1
  • N. Silanikove
    • 2
  • T. Glasser
    • 2
  • Y. Gerchman
    • 3
  • A. Perevolotsky
    • 4
  • S. Lev-Yadun
    • 3
  1. 1.Department of Evolutionary & Environmental Biology, Faculty of Science and Science EducationUniversity of HaifaHaifaIsrael
  2. 2.Institute of Animal ScienceAgricultural Research OrganizationBet DaganIsrael
  3. 3.Department of Science Education - Biology, Faculty of Science and Science EducationUniversity of Haifa, OranimTivonIsrael
  4. 4.Department of Natural Resources, Institute of Field CropsAgricultural Research OrganizationBet DaganIsrael

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