Diving insects boost their buoyancy bubbles

Underwater backswimmers use their haemoglobin to help them stay stationary while waiting for prey.


Backswimmers (Notonectidae) are common diving insects found around the world that exploit the mid-water zone for predation — they breathe by using an air bubble collected at the surface. Here we show that backswimmers achieve prolonged periods of neutral buoyancy by using oxygen stored in their haemoglobin to stabilize the volume of the bubble as they breathe from it. This enables them to maintain their position in the water column without continually swimming.

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Figure 1: Partial pressure of oxygen inside a bubble and the change in the bubble's volume while attached to the insect Anisops deanei during a dive.


  1. 1

    Ege, R. Z. Allg. Physiol. 17, 81–125 (1915).

  2. 2

    Thorpe, W. H. & Crisp, D. J. J. Exp. Biol. 24, 227–269 (1947).

  3. 3

    Miller, P. L. J. Exp. Biol. 44, 529–543 (1966).

  4. 4

    Bare, C. O. Univ. Kansas Sci. Bull. 18, 265–349 (1929).

  5. 5

    Miller, P. L. Nature 201, 1052 (1964).

  6. 6

    Wells, R. M. G., Hudson, M. J. & Brittain, T. J. Comp. Physiol. 142, 515–522 (1981).

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Correspondence to Philip G. D. Matthews.

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Matthews, P., Seymour, R. Diving insects boost their buoyancy bubbles. Nature 441, 171 (2006). https://doi.org/10.1038/441171a

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