Miraculous Mosses

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Mosses are an amazingly resilient and versatile group of plants. They range from microscopic discolourations on the soil to great shaggy knee-high carpets. They can be found in just about every habitat you can think of, from deserts to streams and from the Arctic to the Antarctic.

Masters of suspended animation, you can dry them out completely, subject them to heats of 70 0C (twice as hot as our recent summer heat wave) and on applying water, they will spring back into vibrant life again. (Dried museum specimens, have on occasion, been brought back to life after many years storage, by the simple application of a few drops of water.)

Mosses will grow in deep, dense forests and caves, in light intensities too low for any other green plants to survive. In places like the high Arctic, they are one of the few plant forms that can survive the devastating coldness. Miraculous indeed!

Together with the related liverworts, mosses make up a group of plants known collectively as ‘Bryophytes’. This is a group of non-flowering plants which are considered to be fairly simple in evolutionary terms. Compared to Flowering Plants, such as daisies or dandelions, they have a much less organised structure. They have no true roots and the leaves are only a few cells thick.

*Polytrichastrum formosum (Bank Haircap) - male shoots bearing antheridial cups

Moss reproduction also demonstrates relatively simple characteristics. Their sex life is out in the open rather than hidden from view within flowers. Antherozoids (sperm equivalent) are produced in tiny sacs, called antheridia. On their release from the antheridia, the antherozoids must then swim through surface water to fertilize neighbouring egg cells. These are produced in the base of flask-shaped structures embedded in the moss tissue. This absolute requirement for the presence of a surface water film for successful reproduction, ties mosses to habitats where wet conditions occur at least occasionally.

Although mosses do not produce flowers, in some species, shoots carrying male reproductive organs (antheridia) can look just like small green flower heads (left).


*Polytrichum juniperum sporophytes

Fertilization of an egg cell results in the development of a new, asexual stage in the moss life cycle. This is the sporophyte, consisting solely of a stalked capsule, whose base remains embedded in the parent moss tissue. Sporophytes are mostly non-photosynthetic and remain reliant on the parent plant for nutrients and water.

At certain times of year, most moss species produce large numbers of these capsules, springing up in profusion from the moss carpet like minute forest towers.


Funaria hygrometrica (*Common Cord-moss) capsule with peristome teeth.

Spores are produced within the uplifted capsules and then shed, often using ingenious dispersion methods.

The capsule (left) sheds spores a bit like a pepperpot. It has a peristome with radial teeth which swell or contract depending on the amount of moisture in the air. This has the effect of closing or opening the centre of the peristome. When the peristome teeth contract, opening up a gap, the wind can shake the spores out of the capsule.

When the spores reach a suitable habitat and germinate, each will eventually produce a new moss plant.



*Thanks to Dr Sean Edwards, Keeper of Botany at the Manchester Museum, for kindly supplying some identifications and common names of the mosses pictured above.

The names of the mosses illustrated are included in the image titles. (These titles become visible when you hold your mouse pointer over the image.)