Of course you can pick up objects as small as a mouse. How do you operate your computer otherwise? :D
I often find it useful to finely control how much force I apply, e.g. threading a needle or walking barefoot on rocks. I don't know that my control over how much force I apply has to be as fine as a mouse's, but pretty near.
Article in current Scientific American (first para and bullet points, rest is paywalled).
Podcast by the author (free).
The author, Douglas Fox, argues that there may be physical limits to how intelligent a brain made of neurons can become, limits that may not be very distant from where we are now.
He makes evolutionary arguments at a couple of points, suggesting that he is talking about how smart an organism could have evolved, rather than how smart we might make ourselves; he certainly isn't talking about how smart a machine we might create out of different materials.
From the podcast (I don't have access to the article):
Four routes to higher intelligence, which he argues won't get us very far:
He's described simply as an "award-winning author", but I don't know if he has any scientific background, and there are too many people of the same name to Google him.