Single-Celled Organisms

Individuals can die--when more individuals die than scizm the species will go extinct.

Ummm, yes. What do you think happens when bacteria is exposed to antibacterial compounds like soap and other cleaners?

Understood. Thank you, tsarstepan.

I think all other living things have a parent(s) and often children. In contrast, I think the single-celled organism keeps on dividing without dying unless is is hit with anti-bacterial spray, etc.

Stromatoporoids in the Lexington Limeston: Sponge...

By the trillions.

maybe even quadrillions

Single-celled organisms. Do they die?

Interesting question that was sidestepped in 2012. But it has wider implications. Since they reproduce by fission, they produce clones, exact copies of themselves, actually the same organism. So, they have the potential to live forever.

Then I thought of the smooth sumac--Rhus glabra--, a small tree no more than 8 feet tall and considered a weedy, short-lived thicket-producing tree. And, indeed the individual may only live ten years or so. But the tree puts out rhizomes every year, many of them, and each one sprouting another tree, a clone. The rhizome is an underground stem so you have to think of the whole thicket as one tree. This tree is continually regenerating, and thus has the potential live forever.