The word in question is “contentious.”
Such a shift of Earth is called “true polar wander”, but the evidence for this process has been contentious.
http://astrobiology.com/2021/10/did-the-earth-tip-on-its-side-84-million-years-ago.html
Contentiousness is a human emotion or behavior. It’s not something that inanimate objects such as evidence do.
So I say the sentence should say:
Such a shift of Earth is called “true polar wander”, but the evidence for this process has been a source of contention.
What do you think?
Here’s a picture from the article:
