What Are the Tiny Dots on Thanksgiving Apples and Pears?

An apple in a Thanksgiving fruit bowl can look almost polished until the light catches its little freckles. A pear beside it may have a different pattern: small pale marks, darker dots, or tiny star-like shapes. Many of these ordinary surface markings are lenticels, structures involved in the exchange of gases through the fruit’s outer covering. They offer a small, visible introduction to the less visible workings of a fruit. Research on apple lenticels

A fruit has living tissue inside

Apples and pears contain living cells that carry out respiration. In this process, cells consume oxygen and produce carbon dioxide. Gases move between the fruit and its surroundings, with diffusion playing an important role. The outer covering and the tissues beneath it influence that movement.

Calling lenticels the fruit’s “breathing spots” is a useful first approximation, provided it does not suggest miniature lungs. Fruit has no pumping respiratory organ. Researchers studying gas exchange in pears instead work with oxygen consumption, carbon dioxide production, gas movement, and the actual shape of the fruit. Even a quiet-looking pear is a three-dimensional system. Pear gas-exchange research

Where the dots come from

The skin of a young fruit changes as the fruit develops. In a study of Conference and Clapp’s Favourite pears, researchers found lenticels at the positions of stomata, the small openings present on young fruit, and at places where surface hairs had been lost.

Under microscopes, the pear lenticels included oval and star-shaped forms. Some were open, while others were closed by surface tissues. That variety helps explain why a lenticel is better understood as a small area with a particular tissue structure than as a perfectly round, empty hole. The findings concern those two pear cultivars, rather than establishing one identical pattern for every pear. Microscopy of developing pears

Apples do not wear identical patterns

Lenticels vary across apple varieties and across different parts of the same apple. In a 2020 study, researchers measured differences in their size, density, and combined area between the stem end, the middle, and the blossom end.

The study also measured water-vapor movement. Lenticels contributed to water loss, but their share differed between cultivars and positions on the fruit. The visible dots therefore belong to a working surface whose properties vary. Counting them is not a shortcut to measuring everything that passes through an apple’s skin. Apple-skin measurements

There is another landscape under the skin

A surface opening is only part of the journey. X-ray tomography has revealed spaces between the cells inside apples and pears, allowing researchers to examine the internal routes available to gases without treating fruit flesh as a uniform block.

In the fruit examined in one study, the apple tissue contained larger cells and larger voids than the pear tissue. The pear’s smaller spaces formed a closely connected network around many cells. Those differences in internal architecture helped explain differences in gas movement. A dot visible from the outside cannot show you that whole network. Three-dimensional fruit imaging

A visible dot is not necessarily an open passage

An early investigation following 18 apple varieties documented both open and closed lenticels. Changes in the cells beneath the surface, or a covering of cuticle over the associated opening, could restrict free movement through them. This is another reason to avoid imagining every freckle as an unobstructed tunnel straight into the center. Apple lenticel development

For a Thanksgiving-table observation, compare shapes and spacing rather than trying to diagnose the fruit. Turn an apple slowly under a light, then look at a pear. Are the dots evenly scattered? Do they look round or irregular? Does their contrast change against different areas of skin?

This explanation concerns ordinary lenticels. It cannot identify every mark on a particular fruit or determine its condition from dots alone. The reward for looking closely is simpler: a familiar centerpiece becomes a chance to notice plant anatomy that was there all along.