And this is where it gets even trickier, as mentioned above. A single kelp organism can weigh over tonne, is considered a plant by most people and is certainly not one celled, yet according to most taxonomies it is still a protist. And the reason for that is that it has close relatives that are entirely unicellular.
So here we have a huge, multicellular, photosynthetic organism with a trunk, ‘leaves’ and fruiting bodies that forms forests. But it’s not a plant, it’s a protist.
Meanwhile we can look at some of the corals that are green, immobile, obtain most of their energy from photosynthesis and have a trunk and branches. And they are animals.
Then we look at the saprophytic plants, which are white, threadlike, never see the sun, much less photosyntheise and live entirely on decaying organic matter. And they are still considered plants.
Unfortunately there’s no simple way of defining a plant without referring to ancestry.
Anyone remember that old sci-fi movie, I think it was called The Thing, about the alien that was a plant? It had two arms and legs, and a head. Could move and think. But its cells were what we would consider plant cells.
This thread just got me thinking about that movie. sorry.
Most outdated taxonomies. Protista hasn’t been a useful taxonomic classification for the last generation, at least. Not since biologists decided cladistics is where it’s at.
No, I was not joking. I stand by my statement. Protista has ceased to be a useful classification. That it is still used doesn’t mean it’s useful. As your own kelp example clearly shows. It’s outdated. Eventually the literature will catch up.
BTW, got that cite for the ur-metazooan being photosynthetic, yet, speaking of blatant misinformation?
I should add that I am specifically referring to Protista’s use as a taxonomic classification. For an ecological or morphological scheme, great, use it if you want. But for modern taxonomy, it’s worse than useless, obscuring as it does any real phyletic relationships.
Yeah, it’s outdated and hasn’t been used fo generation… except for all those thousands of scientists publishing in high end journals who used it in the last year.
But they’re all wrong, Mr. Dibble is wisdom wright, and they’ll all realise how wrong they are and acept his wisdom some day.:rolleyes:
Tell ya what dude, when that day arrives you can say the system is outdated. Until then I’ll accept the word of actual taxonomist published inpeer reviewed journals over that of some anonynous internet poster. This the supposed to be a forum for factual answers, not wild proclamations on how your pet theory is the only right one.
I should say that I know that the protists aren’t a clade (that’s what I was alluding to when I referred to them as a sort of catch-all category), but I thought, from the question, that an answer of “six kingdoms” would be more useful than going into the cladistics.
There was nothing exactly *wrong *with your answer (with Blake’s correction to it). Even Blake’s extention of the point re: fuzziness of the concept of “plant” was spot-on.
But if someone asks a question like that in GQ, *not *using cladistics strikes me as about as useful as using Linnaeus’ two-kingdoms model - neither is the current state-of-the-art in taxonomy. And in modern taxonomy, Protista is as useful as Invertabrate. Not totally useless, often convenient, mostly kept around for historic reasons but not hella precise or truly meaningful the way clades are.
As **Blake **has shown, lots of people still use the older classification system, but like I said, that doesn’t make it best practice. And (counter to what Blake seems to think) this is not just *my *opinion - papers get written about this all the time. By the time the dust settles, we may have an 18-Kindgom model, or a 30-Kindgom one, or somewhere inbetween. But that doesn’t mean we have to wait for the final concensus before we can confidently say to any General Questioners that the 6-Kingdom model is outdated.
I should add, that as far as the OP goes, a more meaningful answer would be that Plant and Animal are fuzzy concepts, and does he mean Plantae vs Metazoa, or Photo-autotroph vs heterotroph?
