Ah, the mobile phone. One of the wonders of the digital world, it has given us powers beyond what few might have conceived. But who could have imagined it would become such a ubiquitous tool of narcissism?

Welcome to the Selfie Age. An era where millions of self portraits are shared each day, and in fact, according to data from Samsung, make up almost one-third of all photos taken by people between the ages of 18 and 24. And it doesn’t stop with the kids; posting selfies has seemingly become part of the job description for celebrities, even Michelle Obama and the pope have not proven immune to sharing self-shot snaps.

(Not to mention Geraldo Rivero, who we’re sorry to report posted a semi-nude selfie.)

They have become so predominant that Oxford Dictionaries officially admitted the word “selfie” into the club of legitimate words last year.

And selfies have seemingly invaded every conceivable situation. Selfies at funerals? There's a tumblr site dedicated to that. Selfies at somber places, like Chernobyl and war memorials? Check. Not even a freeway closed to save a suicidal man from an overpass is off-limits, as evidenced by this shot of people taking selfies with a jumper in the background. Have we no selfie shame?

And now the selfie phenomenon has invaded the heavens with a new demographic: flight attendants.

In the latest selfie trend, sexy flight attendants across the globe have started “an underground network of mile-high selfies,” as the New York Post describes it, that they post on Instagram. Stretched out in planes with jaunty uniforms and lips puckered, some flight attendants say that it’s just part of a way to create camaraderie in the high-flying world.

“Aviation is a very close-knit community,” said flight attendant and “Rants of a Sassy Stew” blogger Shawn Kathleen. “We get each other, because we’re living the same lifestyle.”

Community through selfies; what next? It’s as if life is being lived through selfies alone. If Descartes were alive today, his most famous philosophical proposition may have ended up as, “I selfie, therefore I am.”

Yet for all the millions of self portraits shared each day, there is a silver selfie lining. Sometimes, they are being put to good use.

The World Wildlife Fund has launched the #LastSelfie campaign using Snapchat, in which endangered animals with faux selfies plead with viewers to not let this be their #LastSelfie.

If the selfie can save even one endangered species, it might just make the world’s billions of selfies a bit easier to digest.

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Mile-high selfies? Not even the friendly skies are safe from the selfie invasion
From selfies at funerals to selfies by flight attendants, we just can't seem to get enough of ourselves.