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 : So, in summary, you still haven't provided a reference to support you claim, and instead of making a minor correction, you still prefer to just remove everything?! Secondly, if ""you"" in the above comment was aimed at me, please note that I was not the original author of the sentence (you'll have to check history for that); I only added the citation needed tag. I have now re-inserted the sentence, but with a slight change in wording that hopefully will resolved the potential confusion over popular vs. common. I have also added a sentence to the main section, using the reference provided by Kurt Shaped Box above. As was pointed out by Casliber in his last edits to the page, there is a general attempt of restricting ref's in leads since all info in leads should be supported by ref'ed info in the main sections of the article (→WP:LEADCITE). The only sentence that was not clearly supported by ref'ed info in the main part of the article was the one about the Cockatiel, hence my addition of a sentence specific to that case. Finally, please do remember to sign your comments (comments on all talk pages should be signed). That's done by ending the comment with four tiles (~~~~) •  • "