In this case it's not about the order of the words, but your interpretation of the meaning of "alone." Read the headline as it is, a news headline (rather than a scientific conclusion), and it might make more sense.
A good sentence can be a bad headline.
It's the same principle as Murphy's Law in engineering. If it can be interpreted in a different way, you don't put it at the top of your story.
In this case, removing the word "alone" makes a better headline.