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A coat of tiny hairs

Why Is a Peach Fuzzy?

A peach is covered in fine hairs, and a nectarine is the same fruit without them — the difference is one gene.

A peach's skin Thousands of finehairs
The fuzz is not dirt or mould. It is the fruit's coat.
  1. Step 1 of 5

    The hairs are part of the skin.

    Hairs grown from thefruit's own skinDense enough to trapa layer of airThickest while thefruit is youngAbsent entirely in anectarine

    Each one grows out of the fruit's surface, the same way a hair grows out of skin. They stand up in a dense layer over the whole peach.

  2. Step 2 of 5

    They hold a layer of still air.

    Bare skin Wind takes waterstraight offFuzzy skin A trapped layer slowsit down

    Still air next to the skin is what stops water escaping. The fuzz traps a layer of it, so a peach dries out far more slowly than a bare-skinned fruit.

  3. Step 3 of 5

    They also put insects off.

    An insect tryingto land Hairs make ithard to grip orbite

    A layer of hairs makes it hard for a small insect to get a grip or reach the skin to bite. It is a physical fence rather than a poison.

  4. Step 4 of 5

    A nectarine is the same fruit without them.

    A peach One gene switched onA nectarine The same fruit, geneswitched off

    Nectarines are not a cross with anything. A single gene switched off stops the hairs growing, and everything else about the fruit is a peach.

  5. Step 5 of 5

    Smooth skin costs it something.

    Fuzz or no fuzzFuzz: keeps water in, insects outSmooth: bruises and dries faster

    Without the fuzz a nectarine bruises more easily, loses water faster and is more prone to disease — which is why the fuzzy version came first.

    A peach tree can produce both. A branch on a peach tree occasionally reverts and grows nectarines instead.

The short version

A peach's fuzz traps still air to slow water loss and makes it hard for insects to bite, and a nectarine is a peach without it.

Try it yourself

Rinse a peach and watch how the water beads on the fuzz instead of wetting the skin.

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