Male European starlings mimic the sounds they hear. In the U.S. they’re an invasive alien species so they’re allowed as pets (other songbirds are not!). Put the two together and you get a #smartstarling. Click on the image to see the video.
NOTE: If you don’t hear anything when the Twitter video plays, click the speaker icon on the video at bottom right.
(photo from Wikimedia Commons; screenshot from Nick P. Williams @TheFalconBirder)