I'm fighting depression with reading about phylogenic relationships, that is "tree of life" relationships where the branching is specifically considered to determine evolutionary relationships.
Mushrooms are more closely related to people than they are to any plant.http://tolweb.org/Eukaryotes/3
Also, "Malawimonads." That just looks fun. Also, "Protists of uncertain placement."
Another diversion: single celled organisms, how big can they get? A single slime mold is one cell and can cover a square foot.
Here's this candidate, members of the Xenophyophore, a . See http://www.newscientist.com/article/dn18468#.U73XFI1dVBI
"Shunning the convention that single cells are microscopic, Syringammina is a brute, growing to a width of 10 centimetres – and sometimes even twice that." It's much larger than this ameoba that also creates a "test" or shell of sand: http://en.wikipedia.org/wiki/Gromia_sphaerica
. An inch and half is still pretty large for what comes to my mind when one sees the word "amoeba."
Why one particular species of http://en.wikipedia.org/wiki/Caulerpa
isn't the winner, i don't know: "A species in the Mediterranean can have a stolon more than 3 metres (9 ft) long, with up to 200 fronds." Then there's http://en.wikipedia.org/wiki/Acetabularia
. This has only one nucleus, but grows to 10 cm high and has a defined structure (more like a mushroom).
So, you know, when you look at the wiki page for http://en.wikipedia.org/wiki/Valonia_ventricosa
and see the claim that this 2 inch diameter bubble is "arguably the largest single-cell organism" i really have to go back to the algae Caulerpa.
Wait, no "In the genus Halimeda, whole seabed meadows may consist of an individual, single-celled organism connected by filamentous threads running through the substrate." http://en.wikipedia.org/wiki/Bryopsidales
I suppose i am not surprised that the single celled organisms get so large in the seas. They've had a very long time to evolve there.