I looked around for a few pictures of a functioning human liver in
vivo on the Net, and it looks kind of light pinkish-brown from what I
saw (more pink than brown).  And yet illustrations almost always show
the liver as being dark reddish brown, like the beef livers you see in
supermarket meat sections.

What is the _true_ color of a human liver, and if it's not dark
reddish-brown, why is it always illustrated that way?