Well, not quite eternal- around three weeks now, but how knows? It might turn out to be eternal.
Why is it that people applaud for birthdays? Congrats, you survived another year? Well done, we didn't think that you could do it? I mean, applause implies approval- what are we approving here? On the other hand, what are we supposed to do at an announcement of a birthday? Shout happy birthday? surely not sing it? Or simply give a nod of acknowledgement?
Which leads to the bigger question surrounding birthdays- what exactly are we celebrating? It's nice for everyone to have a day in the sunshine, but why the day they are born specifically? It wasn't like they had anything to do with the process.