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The Euler spiral of rat whiskers.

ABSTRACT: 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∘ 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.

SUBMITTER: Starostin EL

PROVIDER: S-EPMC6962041 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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The Euler spiral of rat whiskers.

Starostin Eugene L EL Grant Robyn A RA Dougill Gary G van der Heijden Gert H M GHM Goss Victor G A VGA

Science advances 20200115 3

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 ...[more]

PMID: 31998835

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