Center for Biological Diversity's Endangered Species condoms Credit: Deanna Isaacs

Today, July 11, is World Population Day—an opportune time to guess how many human beings are currently puttering around planet earth.

If 7.5 billion is the number that comes to mind, well, bingo.

The Center for Biological Diversity, which was handing out condoms at Lincoln Park Zoo last week in advance of the big day, wants us to know that this giant number is no cause for celebration. There are way more of us now than there used to be (only 2.5 billion as recently as 1950).  We’re heating up the globe and squeezing out other species, which are going extinct at an equally dizzying rate.  

That’s what inspired the center to create its line of Endangered Species Condoms. They come in packages of two, sporting handsome images of threatened creatures and cautionary rhymes, like “Fumbling in the dark? Think of the Monarch,” or “Can’t refrain? Remember the who0ping crane.”

OK, the poet should probably keep his or her day job. But the condoms are popular gag gifts and conversation pieces. Not sold, they’re only available through the center, which has given away a half million of them so far, all in the U.S.

Volunteers Linda McNay and Joy Schochet, who were manning the center’s display at the zoo’s Adult’s Night Out on Thursday, put anyone who wanted the condoms through a carbon-budget game, making them forfeit a fistful of play money for a variety of global warming activities that might be part of their lives: air travel, meat eating, failure to recycle, and, not least, having kids.

A few facts:

  • The Center says we’re adding 227,000 people every day.

  • While it took until 1800 to build a human population of one billion, the next billion took only 130 years.

  • The United Nations estimates that by the end of this century, we will number more than 11 billion.

  • Most of that growth is now happening in the poorest parts of the world, where people don’t have access to Endangered Species Condoms—or much (if any) other contraception.

Thanks to the Census Bureau, which keeps a running tally, you can get an up-to-the-minute population count here. But consider yourself warned: it’s scary.