Fingerprints, notoriously, do not change – but of course, says Schuckers, they do, particularly in young children.
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The latter is an issue both for newborns and senior citizens, whose prints are less elastic and have thicker ridges, making them harder to read.

We all know how faces change, from beards to glasses to wrinkles beside the eyes. Schuckers says the long and the short of it with face biometrics is that algorithms are far, far better than they used to be, and continually improving. With vast databases of accrued images to learn from, performance rates are near perfect, and algorithms can account for aging with standardized re-enrolments in tandem with passports (i.e. every ten years or so).

The story is different for kids, for whom performance rates remain in the low 90s. “It used to be that it just didn’t work at all,” she says. “But these more advanced algorithms – not trained on children, still trained on adult data – are able to handle more variability and are doing better.”