Algae is commonly known as the green dirty stuff that grows in water bodies, water storage tanks and water channels. Though this is quite sad, it is not surprising as many people see algae as contaminants in water and fish tanks, swimming pools, weeds on waterways, and worst of all, as poisons. This total lack of appreciation for algae stems from the lack of awareness about the world’s most important ‘plant’. This lack of awareness can be seen even from the basic singular and plural word for algae. In fact, a lot of renewable energy proponents will often give their articles titles such as ‘Algae, an untapped biodiesel resource’.

We can have one alga or a couple of algae, but the notion that algae represent everything bad is erroneous. Algae do much more than to be considered obstructive and/or destructive. History has it that algae (blue-green algae) were instrumental to the evolution of organisms. Several billion years ago when uni-cellular life began on earth in the absence of oxygen, algae began releasing oxygen into the atmosphere as a waste product of photosynthesis. Plants, flowers, Timber and other vegetables are also believed to have evolved from green algae and are sustained by the Nitrogen-fixing ability of algae.

Away from history, algae are currently responsible for about half the total volume of oxygen produced on Earth despite constituting only about 10% of total plant biomass on the planet. Algae are the primary producers in the aquatic ecosystem. That is, they are the starting point in the aquatic food web and hence important for the availability of the sea foods we eat. The algae are also sources of various forms of pharmaceutical compounds especially antibiotics and antiretrovirals. The algae fix nitrogen to support life on Earth and are efficient in the use of sunlight. They do not need scarce land and water resources to grow as they can grow in brackish water habitat and/or salt water habitat. The algae can clean up polluted waters and they take up lots of carbon dioxide to grow. They (Cretaceous algae) are largely responsible for the majority of Gas and Oil deposits that we are so heavily dependent on globally and they have been found to be important for the development of third generation biofuel. They have a short lifespan ranging from weeks to months depending on the type of algae and their putrefaction, like the putrefaction of all life forms, are often responsible for some of the unpleasant experiences people have with algae.

While these algae have collectively been instrumental to evolution and the continuous existence of life on Earth, they exist in different classifications. A broad and easy to remember classification is the big and small algae. The big algae commonly called seaweeds are often seen around water bodies like ponds, lakes and oceans. They exist is three groups- red, green and brown algae groups. The small algae on the other hand, are usually very beautiful and very noticeable especially in large blooms. They largely occur in coastal regions or near shorelines. They include the diatoms, dinoflagellates, and the blue–green algae amongst others.

The red algae are mostly (90%) marine and some of them make calcium carbonate structures which are important components of coral reefs. The red algae are the source of agar and carrageenan’s (sulfated polysaccharides used in hundreds of products including ice creams, beer, shampoo and soy milk), and thus are collected for commercial purposes. Some species of the red algae are also usually harvested as Nori, a dried edible seaweed used in the Japanese cuisine, Sushi. The red algae are very beautiful seaweeds and have been found to also contain useful pharmaceutical compounds.

The green algae on the other hand, are mostly found in freshwater. They are the ‘ancestors’ of all land plant flora. The green algae are less beautiful than the red algae and are usually considered invasive or plaguing on most fresh waterways but unknown to many people, they are, more often than not, introduced to such habitats by human accident. An example is the green alga, Codium (‘Deadman’s fingers’) which has been invading the east coast of the U.S. and steadily moving northward and plaguing shellfish industries along the waterway. This, however, does not in anyway mean that they are bad, in fact, Codium has been found to have a complex aromatic composition that give spirits, whiskey and tequila a vanilla-like flavour when infused with Codium. Some species of Codium have coconut and floral aromas. Codium in general, are responsible for the flavours in many sea foods.

Brown algae represents all of the giant and ‘tough’ intertidal seaweeds. The notable Sargassum of Sargasso Sea belongs to the brown algae group. The Sargasso Sea is a vast patch of the North Atlantic Ocean between the United States and West Africa. These are abundant marine organisms that often form large forests and are collected for alginic acids. Alginic acids are polysaccharides which are used industrially in food products thickening, glossy paper production and beer brewing. There are only about 1,500–2,000 species of the brown algae. They are also a source of important pharmaceutical compounds.

Diatoms, a subgroup of small algae, are often very abundant and live within ‘glass’ walls they make from silicon dioxide. These walls are known as frustules and overlap like the cover and bottom of the Petri dish used in scientific laboratories. Diatoms move around and have sex in these frustules. These frustules live for thousands of years and its deposits which are sometimes hundreds of feet thick is called diatomaceous earth (diatomite). Diatomaceous earth is used in pool filter systems, in car polishes, as pest and bug control in animals and as detoxifiers in humans. There are 12,000 known species of diatoms though it is believed that there are as many as 60,000 to 600,000 species.

The Blue–green algae (Cyanobacteria) are also abundant and grow in almost every type of habitat on earth. The Blue-green Algae are the ‘photosynthesizers’ that are important not only for the oxygen they produce, but also for nitrogen fixation. Nitrogen is important in our atmosphere as it prevents the oxygen in the atmosphere from igniting when we strike a match. Plants also need Nitrogen to grow hence a lot of money is spent on the production of nitrogen containing chemical fertilizers that are harmful to our natural environment. When at bloom-level densities, the Blue-green Algae can give water a reddish colouration.

The algal classification will be concluded with Dinoflagellates. This is because this group of small Algae have been associated with paralytic shellfish poisoning, amnesic shellfish poisoning, diarrhetic shellfish poisoning, neurotoxic shellfish poisoning, and ciguatera fish poisoning. Again, despite all these, algae are not to be considered bad. Dinoflagellate poisoning occurs only when there are massive blooms often caused by excessive nutrients from human pollution. Other than this, the dinoflagellates are benign sources of oxygen and food for other organisms. They are also symbionts of corals. Unfortunately, increasing levels of pollution and increasing global (and by extension, water) temperatures are bleaching coral reefs thereby causing the algae to abandon these corals. The abandonment has contributed to the death of majority of coral reefs with a sizeable percentage being threatened. On a fun side, dinoflagellates exhibit bioluminescence and produce dreamlike scenes of people, boats, or dolphins moving through the water at night creating glowing trails.

In summary, the Algae do a whole lot to keepall life forms on earth alive and don’t deserve to be labelled bad. They produce about half the oxygen in the world, they started and now sustain the food web, they are responsible for our oil and gas deposits, they support pharmaceutical research and development, are great potentials for renewable energy and grow with minimal supervision and requirements. Can the people stop seeing the Algae as dirt/pond scum/obstructive seaweed and be thankful to these wonderful, simple creatures?