I to be nibbling on part nori the other day once a assumed suddenly fight me. I don"t know squat about algae. I recognize it comes in numerous shapes, sizes, and also colors. I know it is the stuff the we provided to litter at each various other on the beach. I recognize that it photosynthesizes. That"s around it. What room algae? room they even plants?

The shortest answer ns can give you is "it depends." The term algae is a little bit nebulous in and of itself. In Latin, the word "alga" simply way "seaweed." Algae room paraphyletic, meaning they perform not re-superstructure a recent common ancestor v one another. In fact, there is no specification, algae may refer come entirely different kingdoms the life including Plantae (which is often divided in the vast sense, Archaeplastida and the narrow sense, Viridiplantae), Chromista, Protista, or Bacteria.

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Caulerpa racemosa, a beautiful environment-friendly algae. Picture by Nhobgood Nick Hobgood license is granted under CC BY-SA 3.0


Taxonomy gift what it is, these groupings might differ relying on who girlfriend ask. The suggest I am trying come make right here is the algae space quite diverse from an evolutionary standpoint. Also calling them seaweed is a little misleading as numerous different varieties of algae have the right to be uncovered in fresh water and also growing top top land.

Take for circumstances what is described as cyanobacteria. Known commonly as blue-green algae, nests of these photosynthetic bacteria represent some that the earliest proof of life in the fossil record. Stays of early american blue-green algae have actually been found in rocks dating back much more than 4 exchange rate years. As a whole, these varieties of fossils represent practically 7/8th of the history of life ~ above this planet! However, lock are considered bacteria, not plants.

Diatoms (Chromista) are another enormously crucial group. The solitary celled, photosynthetic organisms room encased in beautiful glass shells that comprise entire class of geologic strata. They make up a majority of the phytoplankton in the world"s oceans and also are necessary indicators of climate. However, castle belong to their very own kingdom the life - Chromista or the brown algae.

To bring it earlier to what constitutes true plants, over there is one team of algae that really began it all. That is widely believed that land plants share a nearby evolutionary background with a branch of green algae known as the stoneworts (order Charales). These aquatic, multicellular birds superficially resemble plants with their stalked appearance and radial leaflets.


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It is most likely that land plants developed from a Chara-like ancestor the may have resembling modern day hornworts that stayed in shallow freshwater inlets. Estimates of as soon as this take place go earlier as far as 500 million years prior to present. Unfortunately, fossil proof is thin for this kind of thing and also mostly come in the form of fossilized spores and molecular clock calculations.

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Porphyra umbilicalis - one of the many types of red algae commonly referred to together nori. Photograph by Gabriele Kothe-Heinrich licensed under CC BY-SA 3.0


Now, to carry it back to what began me under this road in the first place. Nori is made from birds in the genus Porphyra, i beg your pardon is a type of Rhodophyta or red algae. In addition to Chlorophyta (the green algae), they consist of some of the most familiar groups the algae. Lock have also been the resource of a the majority of taxonomic debate. Recent phylogenetic analyses place the red algae as a sister team to all other plants starting with environment-friendly algae. However, part authors choose to take a broader look in ~ the tree and thus bump red birds in a member of the plant kingdom. So, relying on the particular paper I am reading, the nori i am at this time digesting might or might not be considered a plant in the strictest sense of the word. The being said, the lines room a little bit blurry and also frankly ns don"t really care as lengthy as it tastes good.

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In Evolution, general Botany, Plants, Taxonomy tag algae, plants, alga, plantae, plant evolution, Archaeplastida, Viridiplantae, Chromista, Protista, Bacteria, cyanobacteria, red algae, environment-friendly algae, diatoms, Caulerpa, Caulerpa racemosa, stonewort, Chara, Charales, Chara braunii, nori, Porphyra, Rhodophyta
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