Research Highlights: Indian Jumping Ants Can Shrink and Regrow Their Brains

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Indian Jumping Ants Can Shrink and Regrow Their Brains

April 18, 2021

  • Changes in observable characteristics allow organisms to respond to changing environments.
  • However, these changes are usually not reversible.
  • A long-lived vertebrate species was observed to exhibit seasonal changes in brain size.
  • Similar changes have not been observed in short-lived species like insects.
  • Researchers revealed a change in brain size of reproductive worker ants Harpegnathos saltator also known as Indian jumping ants.
  • H. saltator worker ants are capable of sexual reproduction, unlike most ant species.
  • They compete in a dominance tournament to establish a group of reproductive worker ants called “gamergates”.
  • In comparison with the foragers who usually search for food, gamergates show a 19% reduction in brain volume.
  • They also differ in behavior, ovarian status, cuticular hydrocarbon profile, venom production, and expression profiles of related genes.
  • Researchers manipulated gamergates to observe the traits.
  • After 6-8 weeks from being reverted back to non-reproductive status, their observable traits changed to the forager type across all traits they measured.
  • The changes in traits include brain volume which changes were shown to be irreversible in Drosophila and honeybees.
  • The change in brain size of H. saltator is more similar to that found in some long-lived vertebrates that display reversible changes in brain volume.

Source:

Penick Clint A., Ghaninia Majid, Haight Kevin L., Opachaloemphan Comzit, Yan Hua, Reinberg Danny and Liebig Jürgen 2021Reversible plasticity in brain size, behavior and physiology characterizes caste transitions in a socially flexible ant (Harpegnathos saltator)Proc. R. Soc. B.2882021014120210141. http://doi.org/10.1098/rspb.2021.0141