But I was looking at sources from the past and many reported that it was the wings that did the humming, The question here comes from noticing that a student was the one that found about this, how come many experts missed it for so many years?
Or it was a secret kept by Colibri? 
Just a comment about the term ‘student’ in this context. The student, Christopher Clark, is almost certainly a graduate or even a postgraduate student. As such, he is probably just as advanced, if not more, than many of his profs. More to the point, in research work, it is often the student who is the first author of the paper even though the results may reflect, and are almost certainly built upon, the techniques developed and results already established, by the supervising professor and his/her “group”. In this case, that would be the senior author, Richard Prum. His academic title and biography on Wiki suggest he is a very accomplished ‘evolutionary ornithologist’.
I really did not know that.
Ignorance fought! Thanks KarlGauss
For every story of an advisor stealing authorship from some poor student, there are many unreported cases of the opposite. I’m sure Clark did a huge amount of work on this—he didn’t get a “gift” from Prum—but as KarlGauss said, it was undoubtedly a group effort. Any number of people may legitimately be first author on a paper, perhaps with a bit of shuffling of responsibilities, but as for career impact, giving this to the student is huge. Prum is well established, and simply having his lab produce a Science paper is all he probably cares about. For a student though, getting a first author paper in Science can launch his career.
Either way, it is a very cool finding, and if it stands up, then it is one more step of scientific progress. We thought we knew how something worked, but then it turned out (there’s a good chance) we were wrong.
So Christopher Clark is saying that only males hum?
I’ve got a bunch of female ruby-throat hummers that visit me every day, and they all hum like crazy. Not a male in the bunch.
As is often the case with popular science writing, the article cited in the OP gets the significance of the research almost completely wrong. The characteristic humming sound made by hummingbirds is made by the wings. Christopher Clark’s research instead is on the sounds made during diving courtship displays by males of certain hummingbird species, mainly members of the genus Selasphorus, which includes Broad-tailed, Rufous, and Allen’s Hummingbirds in the US, and Calypte, which includes Anna’s and Costa’s Hummingbirds. These sounds might better be described as peeps, buzzes, or whistles than humming.
It had been thought that these sounds might be produced by the wings, but Clark has shown they are actually made by the vibration of modified tail feathers. Here’s a link to a better description of the research, including a video of Clark explaining it and examples of the sounds. Here’s the abstract of the actual Science article.
I met Clark at a conference in Brazil last year, and had a chance to discuss his research with him. Clark is a post-doc in Prum’s lab (who I also know). I wouldn’t describe a post-doc as a “student.” I’m particularly interested because there’s an endemic Selasphorus species in Panama, the Glow-throated Hummingbird, whose courtship display has never been described and which Clark is also interested in investigating.
I just knew I should had mentioned that I suspected something else was not quite right with this bit of news, the press getting science wrong? Not the first time.
It is brutally cool that you know the people involved Colibri, thanks for the great info.
There was a PBS documentary that aired a while back that explained the whole tail noise thing. It was fascinating.
And, as Colibri reveals, it made quite clear that the tail noise was made during courtship diving, and was quite different from the regular hum of their wings.