The Euler spiral of rat whiskers
E.L. Starostin, R.A. Grant, G. Dougill,
G.H.M. van der Heijden & V.G.A. Goss
This paper reports on an analytical study of the intrinsic shapes of 523
whiskers from 15 rats. We show that the variety of whiskers on a rat's
cheek, each of which has different lengths and shapes, can be described
by a simple mathematical equation such that each whisker is represented
as an interval on the Euler spiral. When all the representative curves of
mystacial vibrissae for a single rat are assembled together, they span an
interval extending from one coiled domain of the Euler spiral to the other.
We additionally find that each whisker makes nearly the same angle of 47
degrees with the normal to the spherical virtual surface formed by the tips
of whiskers, which constitutes the rat's tactile sensory shroud or `search
space'. The implications of the linear curvature model for gaining insight
into relationships between growth, form, and function are discussed.
keywords: whisker, vibrissa, rat, Euler spiral, morphology, intrinsic
curvature
Science Advances 6, eaax5145 (2020)