Not explained as in "through text", but through gameplay.
Yep! The ear things also increase in number.
I thought the extra sprites for collection were a nice touch, maybe too subtle if people are missing it, but I noticed the change and it clicked. The understated design and teaching is nice, but hard in jams because I think we’re all playing a little quicker than we normally would because we want to try and give as much feedback as we can during whatever allotted time we have for a session, so you can miss a subtle hint that your abilities have shifted.