That was my first thought on seeing the second picture, but that's not what's being discussed: 'The shape that Bertoldi and colleagues at SEAS unexpectedly enc

That was my first thought on seeing the second picture, but that's not what's being discussed: 'The shape that Bertoldi and colleagues at SEAS unexpectedly encountered is a hemihelix with _multiple_ “perversions.”' [...] 'there is a critical value of the aspect ratio at which the resulting shape transitions from a helix to a hemihelix with _periodic reversals_ of chirality'. A phone cord may have multiple reversals, but they almost certainly won't be periodic.