The term bird brain is particularly inappropriate. The idea that birds' brains are primitive was based on studies of their structure, which differs substantially from mammalian brains. More recent studies based on function show that bird brains are very efficient and process information in very different ways from ours. It seems clear that evolution wouldn't favor a big brained bird, nor would an inefficient brain permit navigating a woodlot at high speed. You can't survive 250 million years an be dull witted. When an if our species exists as long as the birds have then maybe we can "crow" about our intelligence.