Buttons not working

when I click on the button at the right hand side to view other options it shows nothing except changing the position of arrow UP and Down. Attached is the screen shot.

I just updated the version from 7.1.6 to 7.2. But in my current site when I try to use drop down buttons in Members section, Public photos etc.., it just change the arrow position, but i don't get any option like Latest/Online etc.