After the European (re-)discovery of the Americas, there was a widespread transfer of animals, plants, culture, human populations, communicable diseases, technology and ideas between the Americas and the Old World (primarily Europe). This became known as the Columbian Exchange).
Some examples of this, in the form of animals and food stuffs, would be the potato and the horse.
Before the Columbian Exchange, (white) potatoes were unknown to the old world. After being brought back by traders and merchants, they were fairly quickly adopted as a staple food stuff, providing much needed starches. Although not completely related to just the potato blight disease, the fact that potatoes were ruined as a crop throughout Europe in the 1840's was a leading factor in the creation of the Great Potato Famine of Ireland. This famine (and admittedly other factors as well) caused the population of Ireland to drop by 1.5 million from 1841 to 1851, instead of the expected raise of about a million.
During the exploration of the Americas, the Europeans brought many things with them (including disease), such as the domesticated horse. With the horse, the North American West was conquered (indeed nothing is, IMO, as American as the American Wild West). It can be said that some tribes of Native Americans became more accomplished at horsemanship than the peoples who brought them over.
I really don't want to get into a political (Meiji Restoration) or medical (diseases) discussion, but would rather just discuss 'fun facts', perhaps food stuffs or animals, as discussed above.
Were there any foods introduced into the Japanese culture AND accepted by them to the point of being called, perhaps, a staple food? What about any taken from them back to the Old World?
Were any animals introduced into Japan by Europeans that are now treated as 'a part of the natural fauna' of Japan? Or the other way?