By Gisela Sepulveda
Ever heard of diatom? No? You're not alone. These beautifully patterned, unicellular phytoplankton (a group of algae) are often overlooked, literally. Diatoms are small (and when I say small I mean microscopic) with the cells ranging from 2 to 500 microns (or 0.002-0.5 mm). However, although
they are small they have a massive impact on our lives.
The Art of Diatoms
Diatoms live in aqueous environments; from rivers and oceans to bogs and damp rock surfaces. They
are nature's own artwork coming in a range of weird and wonderful geometric shapes. They have even been used in art, an example of this is Klaus Kemp's work which uses a beautiful arrangement of diatoms to create a large variety of patterns. Kemp has revived this Victorian era art form using updated techniques and microscopes to arrange diatoms on slides, creating a stunning kaleidoscope of these phytoplankton. Diatom art has also seen a revival in the recent documentary by Matthew Killip, who has been able to capture these inspiring patterns of natures work.
Thomas Comber continued the examination of diatoms developing a large collection of slides, bottles and notes that can be viewed online and at the Natural History Museum. As a young man he took up microscopy, travelling far and wide from collecting diatom samples from a variety of aqueous environments. In a recent volunteer programme - Making the Invisible Visible - Thomas Comber's diatom specimens were set up in the specimen preparation area of the Darwin Centre at the Natural History Museum to convert each of these slides and notes into an online database for worldwide use.
Diatoms are more than just nature's mobile art gallery, playing an important role in helping to predict
climate change. They are used in palaeoclimatology, the study of past climates, as they are great environmental indicators, being very sensitive to environmental changes and ecological conditions. As they have silica cell walls, which are deposited and preserved in sediments, they can record past changes in climatic environments which can actually be measured and studied, a useful trope in predicting future climatic changes. They can indicate sea temperatures, acidification levels, river quality, the amount of oxygen or carbon in the atmosphere and much more.
They don't merely act as beautiful indicators of change, they impact on it also. As diatoms are phytoplankton they use photosynthesis to live. This means they produce oxygen, in fact, they contribute to the production around ¼ of the oxygen we breathe. As they take in carbon dioxide from the ocean, infiltrated from the atmosphere, they are also key players in carbon fixation. They can even fix the same amount of carbon (per day) as a forest of plants. So you can breathe easy
now thanks to our small friends!
You may be surprised to know that the diversity of uses of diatoms or diatomite (a white silica rich mineral). It can be found in everyday items from nail polish and paint, to insecticides and fertilisers. Alfred Nobel would not have been able to create dynamite without them, the cats eye road markings are lit up by the reflecting diatom shell and that nice glass of wine at the end of the day
was purified by diatoms. What pearly whites you have, thank diatoms! The silica from diatom cell walls has mild abrasive properties due to which they are sometimes used in whitening tooth pastes. They can even be used in nanotechnology, swimming pool filters and are useful in forensics as well.
So don't overlook our friends; The Diatoms