Why do we say on the team and not in the team? [duplicate]

"on" vs "in" tends to be the result of metaphor - how we understand things in terms of other things. "in" makes sense if you think of a group of people, and the team member is in the middle of that group.

However, imagine writing the team names out on paper, compiling the team list. The player's name would be on the page, and if the page defines the team (which it does, in terms of listing who is in the team), then the player is on the team.

So, when people say "in the team" they may be thinking of an actual group of people, standing by the pitch, say, and when they say "on the team", they may be thinking of a list of players, and perhaps the process of deciding who is on that list.

As another example, think of someone saying "I play in a softball team". They are thinking of the other players. But in another situation they might say "I'm on the team for the easter tournament", meaning that they have been selected, ie added to a list.

Both metaphors are equally valid, and so "on" and "in" are both acceptable.

On reflection, I could have simplified this explanation by saying that "team" has multiple meanings: one meaning is the actual group of players, and another meaning is the list of players. We use "in" with the group and "on" with the list.