Human evolution: fingerprint fine sensitivity (Introduction)

by David Turell @, Monday, March 15, 2021, 17:51 (1137 days ago) @ David Turell

The use of our hands in very refined:

https://www.newscientist.com/article/2271320-fingerprint-ridges-carry-nerve-endings-tha...

"Our fingertips have an extraordinarily high sensitivity to touch – and now it looks like that sensitivity might be largely confined to the ridges of our fingerprints.

“'They really help us get very detailed information about what we touch,” says Ewa Jarocka at Umeå University in Sweden.


"Scientists have suspected that our circular, winding fingerprints might have evolved to improve our ability to grip objects by creating better friction, says Jarocka. But she says others have suggested they might contribute to our “very refined sense of touch”.

***

"The results allowed the researchers to map out exactly where on the fingertips the information that was sent to the nerve was collected. These sensitivity hotspots turned out to be very small, each only about 0.4 millimetres wide.

"What’s more, these hotspots followed specific patterns on the fingertips – the same ones as the fingerprint ridges. Regardless of how the researchers moved the dotted card over a finger, its hotspot map stayed the same, suggesting the sensitivity zones were “anchored in the very stable structure” of the ridges themselves, says Jarocka.

“'We have all those multiple hotspots, and each one responds to the details of 0.4 millimetres, which is the approximate width of the [fingerprint] ridge,” she says. “Then our brain receives all that information. This really offers an explanation to how it’s possible that we’re so dexterous and have such a high sensitivity in our fingertips.”

"This doesn’t mean fingerprints might not have other functions as well, however – perhaps including improving grip, says Jarocka. But it does reveal the important role that the ridges play in touch.

“'Now that we know that the single neuron can be so sensitive on such a [precise] scale, we can finally explain how people can be so detail-sensitive,” she says."

Comment: We do not know when fingerprints appeared on our evolution. We are now learning their usefulness. Is this another 'stasis problem' appearing long before we developed fine use like violin playing? I would think so. Another special attribute in advance designed by God


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