https://onlinelibrary.wiley.com/doi/10.12705/642.12

I'm finding it surprisingly hard to find sources for known age of species - is that information collected somewhere? Or is it something we often just don't know because of how sparse the fossil record is?

Wondering because of trying to look up the age of fern species I do eat (no cinnamon fern near me) and I can't find out.

Isn't the first dinosaurs appeared like 400m years ago, but Ginkgo only 290m?

https://en.wikipedia.org/wiki/Fiddlehead

The actual fruit (looks like a rotten plum, smells terrible) has ginkgolic acids which cause contact dermatitis (think poison ivy).

Then the nuts themselves contain Ginkgotoxin, which interferes with your B6, screwing up your nervous system and causing seizures. Cooking reduces but does not eliminate Ginkgotoxin.

I only ate one, and ate it raw. It was a delightful texture, but tasted like chewing random plant matter. Like leaves from a tree. Was maybe half a cubic centimeter of matter. Escaped any ill effects.

According to my research, kids can have seizures from as few as 10 nuts, which would probably be like 1.5 spoonfuls if you mashed them up. The guidelines I found don't seem very scientific but supposedly a kid can safely handle 3-5 nuts over the course of a day, and an adult could handle 5-10. So it doesn't seem like there is a good margin of safety.

Overall a real risk to health for an insignificant amount of food that doesn't taste special. But a nice texture.