Indian Jumping Ants Can Shrink and Regrow Their Brains
- 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
