I was nibbling on some nori the various other day as soon as a thought unexpectedly hit me. I do not understand squat about algae. I know it comes in many kind of shapes, sizes, and colors. I understand it is that stuff that we provided to throw at each other on the beach. I recognize that it photosynthesizes. That"s around it. What are algae? Are they even plants?
The shortest answer I can provide you is "it counts." The term algae is a bit nebulous in and also of itself. In Latin, the word "alga" sindicate indicates "seaweed." Algae are paraphyletic, interpretation they do not share a recent common ancestor through one another. In fact, without specification, algae may describe entirely various kingdoms of life consisting of Plantae (which is regularly split in the broad feeling, Archaeplastida and the narrow sense, Viridiplantae), Chromista, Protista, or Bacteria.
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Caulerpa racemosa, a beautiful green algae. Photo by Nhobgood Nick Hobexcellent licensed under CC BY-SA 3.0
Taxonomy being what it is, these groupings might differ relying on who you ask. The suggest I am trying to make below is that algae are fairly varied from an evolutionary standpoint. Even calling them seaweed is a bit misleading as many different species of algae have the right to be uncovered in fresh water and also flourishing on land also.
Take for instance what is described as cyanobacteria. Known frequently as blue-green algae, swarms of these photoartificial bacteria represent some of the earliest proof of life in the fossil record. Remains of early american blue-green algae have actually been found in rocks dating back more than 4 billion years. As a entirety, these kinds of fossils represent nearly 7/8th of the history of life on this planet! However, they are considered bacteria, not plants.
Diatoms (Chromista) are an additional enormously important team. The single celled, photoartificial organisms are encased in beautiful glass shells that consist of whole layers of geologic strata. They make up a bulk of the phytoplankton in the world"s oceans and also are crucial indicators of climate. However before, they belengthy to their own kingdom of life - Chromista or the brvery own algae.
To bring it back to what constitutes true plants, tbelow is one team of algae that really began it all. It is widely believed that land also plants share a cshed evolutionary history with a branch of green algae recognized as the stoneworts (order Charales). These aquatic, multicellular algae superficially resemble plants via their stalked appearance and also radial leafallows.
It is most likely that land plants developed from a Chara-favor ancestor that might have resembling modern day hornworts that lived in shenable freshwater inallows. Estimates of when this happen go earlier as much as 500 million years before existing. Unfortunately, fossil evidence is sporadic for this sort of thing and also mainly comes in the create of fossilized spores and also molecular clock calculations.
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Porphyra umbilicalis - One of the many species of red algae generally referred to as nori. Photograph by Gabriele Kothe-Heinwealthy licensed under CC BY-SA 3.0
Now, to bring it back to what started me dvery own this road in the initially location. Nori is made from algae in the genus Porphyra, which is a form of Rhodophyta or red algae. Together via Chlorophyta (the green algae), they comprise some of the a lot of acquainted groups of algae. They have actually likewise been the source of many taxonomic debate. Recent phylogenetic analyses location the red algae as a sister group to all various other plants beginning with green algae. However before, some authors choose to take a more comprehensive look at the tree and therefore lump red algae in a member of the plant kingdom. So, depending upon the particular paper I am reading, the nori I am currently digesting might or might not be taken into consideration a plant in the strictest sense of the word. That being said, the lines are a bit blurry and also frankly I do not really treatment as long as it tastes good.
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In Evolution, General Botany kind of, Plants, Taxonomy Tags algae, plants, alga, plantae, plant development, Archaeplastida, Viridiplantae, Chromista, Protista, Bacteria, cyanobacteria, red algae, green algae, diatoms, Caulerpa, Caulerpa racemosa, stonewort, Chara, Charales, Chara braunii, nori, Porphyra, Rhodophyta
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