Slowest heartbeat

Slowest heartbeat

Last updated: October 13, 2017 at 16:32 pm

The narwhal (Monodon monoceros) can slow its heart to as little as 4 beats per minute during a dive. A study published in 2014 revealed significant changes in heart rate when alternating solutions of high-salt and fresh water are exposed to the Narwhal’s external tusk surface. The narwhal’s tusk is also the world’s most sensitive tooth.

SOURCE:

Nweeia, M. T., Eichmiller, F. C., Hauschka, P. V., Donahue, G. A., Orr, J. R., Ferguson, S. H., Watt, C. A., Mead, J. G., Potter, C. W., Dietz, R., Giuseppetti, A. A., Black, S. R., Trachtenberg, A. J. and Kuo, W. P. (2014), Sensory ability in the narwhal tooth organ system. Anat. Rec., 297: 599–617. doi:10.1002/ar.22886

A pod of narwhals. Note the spiral configuration of the single tusk. Photo by Dr. Kristin Laidre, Polar Science Center | NOAA (Public Domain)

Narwhal pod off Greenland. Photo by Dr. Kristin Laidre, Polar Science Center | NOAA (Public Domain)

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