Hundreds of animal lovers took a walk on the wild side last night, running through London Zoo totally in the buff.
Nearly 300 sponsored streakers of all shaped and sizes earned their stripes baring their flesh in support of the ZSL Sumatran Tiger Campaign.
Showing more than a bit of bare faced cheek, supporters of the cause stripped down to raise awareness that there are only 300 Sumatran tigers left in the wild.
Wearing nothing more than trainers, and in some cases a splash of tiger-themed body paint, the brave runners ran a 300m course through the centre of the zoo watched by their supporters and some rather bemused-looking animals.
In a roaring success, the raised some £60,000.
The hard-earned money will now be put towards conservation work to protect the incredibly rare species of tigers.
Brave participant Nic Coles, 34, from Biggin Hill, Kent, said it was "a great event".
"I was a bit nervous at first, but after seeing so many people turning out for it, it made it feel a lot easier." he said. "If it helps the tigers, I'd do it all over again."
Fellow streaker Son Osman, 31, from Bromley, south east London, said he had "jumped at the chance" to take part in the run.
Explaining why, he said: "It was the chance to get naked in a zoo, for the tigers. It was very liberating, and quite a unique experience."
James Wren, development director at ZSL, said: "Everyone got so excited about the event, they really got behind it.
"There was an amazing buzz in the crowd, both from the spectators and the participants who were running around naked. We only asked them to do one lap, but many carried on doing several laps around the zoo because they felt so liberated and free.
"The feedback has been overwhelming, from those involved in naturism to those who are just passionate about tigers. They were apprehensive and nervous, but when they were doing it, they just enjoyed it so much, they were delighted."