Are seaweed and algae the same thing?

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Sorry if that’s a dumb question. From wikipedia, it seems like they are: “Seaweed is a loose colloquial term encompassing macroscopic, multicellular, benthic marine algae.” Or is seaweed a certain kind of algae, so all seaweed is algae, but not all algae is seaweed?

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Topics: science, biology, ocean, taxonomy, algae, seaweed

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Seaweed generally refers to the leafy/mossy stuff that is attached to rocks and sways in the tide. As a term, it sometimes refers to actual marine plant-life, and sometimes to algae-cousins that are physically similar to plants but evolutionarily different (such circumstances are called convergent evolution)

Algae generally refers to the colored soupy stuff that is gunk/mold-esque, like what you might find in a swamp or a really gross pond. Most of it is single-celled goop. Call it “algae” with no capital letter.

Algae, capital A, is also a much larger grouping of “simple” forms of life, of which both “seaweed” and “algae” are members, as are Lichens and Coral.

So, Certain kinds of seaweed are Algae, some seaweed is not Algae at all. Seaweed is not “algae” (the unicellular stuff).

Also, there are a lot of kinds of algae that are not seaweed, but are still Algae.

aphilotus (2219

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@aphilotus you sure about coral being in that family. I mean im aware most corals host zooxanthellae algae inside of it but didnt think they were in the same grouping.

uberbatman (14813

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augustlan (20071

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@uberbatman You’re right. I always forget that Coral and Lichen are like weird algae symbionts, and not themselves algae.

aphilotus (2219

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@aphilotus yea, im not sure how it works with lichen, but with coral, the zooxanthellae 0-algae takes in light to photosynthesize and produce more. All the extra algae produced is used to feed the coral—(though they still do eat other foods) Its this algae that also gives coral its bright vibrant colors.—

uberbatman (14813

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Corals are members of the Class Animalia, family Cnidaria…ie they aren’t plants, but they have a symbiotic relationship with unicellular algae (zooxanthellae).

Lichens consist of a symbiotic relationship between a fungus and either green algae or a cyanobacterium.

Algae may be unicellular or multicellular. When benthic, marine/or brackish water, and multicellular it is generally referred to as seaweed.

Critter38 (2095

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