"As if to say thank you" isn't suggesting how he looked.
A snake can't look like it's saying thank you. That's a why, not how."
so a person/bird/or anything else cannot LOOK happy even though they are not?
So this dog doesnt /look/ happy
http://media.tumblr.com/tumblr_m5iqywKw1j1r3v72c.jpg
and this cat doesnt /look/ sad
http://25.media.tumblr.com/tumblr_m9...3xaro1_400.jpg
oh- what about this bird- it doesnt /look/ shocked
http://2.bp.blogspot.com/-MYxYEkdyTE...ared+bird.jpeg
and this lizard, it cant possibly /look/ happy
http://openwalls.com/image/12357/thu...py_lizard.jpeg
They may not be the above emotions but they do /look/ on the same line as the emotions.