And no, it's not having a group photo as your primary picture (but that needs to stop immediately too).

This Saturday is International Tiger Day - a day of celebration and recognition for tiger conservation around the world. To raise awareness, animal rights group PETA has penned a letter to Tinder co-founder Sean Rad about the use of 'Guys with Tigers' pictures on his app. Have a swipe through the app and you're sure to find an abundance of photos of people posing with endangered animals while on holidays. PETA says that these kinds of photos are perpetuating an industry of animal cruelty. They could also be encouraging more and more people to become unintentionally involved with this problem. According to the group:

"Baby tigers and other animals used at photo attractions are typically torn away from their distraught mothers when they're just days old and then subjected to extreme stress and physical abuse. Once they've grown larger and are too dangerous to handle, they end up being locked away in cages or heavily sedated."

There are now less than 4,000 tigers left in the wild today. In the early 1900s, this number was close to 100,000. PETA's letter asks that Rad, *ahem* "help protect pussies by banning the most selfish selfie of all" - the tiger one. Instagram account 'tinderguyswithtigers' hosts many examples of this specific kind of picture... and there are a lot more than we expected.

A post shared by @tinderguyswithtigers on Jun 25, 2015 at 6:44pm PDT

A post shared by @tinderguyswithtigers on Jun 13, 2015 at 2:39pm PDT

A post shared by @tinderguyswithtigers on Nov 20, 2014 at 4:28pm PST

PETA's letter ends by suggesting that the company "take the tiger stripes out of swipes" to help end animal cruelty. It's clear that this craze is certainly a lot more popular than we thought.