Participants take part in the so-called “Bearded Men” parade in the streets of Slawatycze village, eastern Poland, 29 December 2023. “Bearded Men” is an old local tradition, passed from generation to generation. In last three days of December, costumed citizens of Slawatycze say goodbye to the old year and make wishes for the New Year. (Photo by Wojtek Jargilo/EPA/EFE)

The photo project was done for the organization Fishlove and included some other U.K.-based celebrities posing in the buff with critters ranging from bass fish to sharks. Its goal is to raise awareness of how overfishing is destroying the oceans. The release of Gillian's nearly nude pic, which was snapped by French portrait photographer Denis Rouvre, is timed with a European Parliament vote on banning destructive forms of deep-sea fishing in the Northeast Atlantic. The Fishlove organization is trying to rally voters to sign a petition ending deep-sea trawling – which, according to scientists, is negatively impacting the fish population and their habits – and Gillian solicited signatures in a Twitter post. Photo: “Fish Love” Project by Photographer Denis Rouvre. Gillian Anderson. (Photo by Denis Rouvre)

Pokot men carry a part of a carcass of a bull killed by a young man during an initiation ceremony in Baringo County, Kenya, January 20, 2016. Far from the bustling city of Nairobi, in an isolated corner of Kenya's Rift Valley, young men from the Pokot community spear a bull in a ceremony called Sapana that takes them into adulthood. (Photo by Siegfried Modola/Reuters)

Models present creations during the 8ON8 PRESENTED BY GQ China catwalk show at London Fashion Week Mens Spring/Summer 2020 in London, Britain, January 5, 2020. (Photo by Henry Nicholls/Reuters)

Kieran Woolley of Australia crashes into a cameraman during mens park skateboard at the Olympics at Ariake Urban Park, Tokyo, Japan on August 5, 2021. (Photo by Lisi Niesner/Reuters)

Women tear the shirt off a man during “Huranga”, a game played between men and women a day after Holi, at Dauji temple near Mathura, March 14, 2017. (Photo by Adnan Abidi/Reuters)

People attend the C2H4 catwalk show at London Fashion Week Men's in London, Britain January 6, 2019. (Photo by Henry Nicholls/Reuters)

Two men standing on a high catwalk, surveying the construction of the Brooklyn Bridge, with Manhattan in the background, New York City, 1877. (Photo by Museum of the City of New York/Archive Photos/Getty Images)