[kuhewa]

We don't teach theories in primary and secondary education when they are first proposed though. And don't come at me with the Wikipedia summary intro paragraph sir — Margulis started promoting the idea in 1967 with a theory paper, she didn't substantiate it with new evidence. It required the genetic evidence later decades would bring to really substantiate.

And yes, no one has questioned the existence of mitochondria for a good long while now.