could anything [cat/squirrel] have been trying to climb up it? are the stalks where they join the main stem damaged?

Hi, I would think that these leaves are being shed,as they are, as the plant gets larger, this is quite normal, and you can just leave them alone to eventually drop off, or you can help them along, if you feel they make the plant look untidy, Derek.

My first impression was a cat, squirrel or some animal tried to climb it and fell down.