Clathrin-coated pits and vesicles Both endocytosis of material at the plasma membrane and exocytosis from the Golgi apparatus involve the formation of clathrin-coated pits and vesicles.
All those things are awesome. But it wasn't until the appearance of birds and mammals that some animals' brains came to be dominated by the last of the five vesicles, the telencephalon.
科学快报-科学美国人2023Science Quickly, from SCIENTIFIC AMERICAN 2023
And once we saw that they were the same as a subset of the ones in the synapse, we can pinpoint them and say, well, that's how the synaptic vesicle works.