The first "true mammal" to sense prey by their electric fields

Electroreception in the Guiana dolphin (Sotalia guianensis)

Nicole U. Czech-Damal, Alexander Liebschner,Lars Miersch,Gertrud Klauer,Frederike D. Hanke,Christopher Marshall,Guido Dehnhardt,and Wolf Hanke

Published online before print July 27, 2011, doi:10.1098/rspb.2011.1127 Proc. R. Soc. B

The South American  Guiana dolphin (Sotalia guianensis) has just been described as the only  "true mammal" to sense prey by their electric fields. Even though Electroreception is well known in fish and amphibians, till now the only mammal example was the platypus.

In the paper referred to above the scientists  show that the hairless vibrissal crypts on the rostrum of the Guiana dolphin, structures originally associated with the mammalian whiskers, serve as electroreceptors in Guiana dolphin.

The researchers recorded a sensory detection threshold for weak electric fields of 4.6 µV cm⁻¹, which is comparable to the sensitivity of electroreceptors in platypuses.

Now the researchers plan to investigate whether other cetaceans possess the same ability.