Video footage shows the pair looking somber as they hold the bodies of animals who'd been killed by humans on factory farms.
They both dressed in black, wearing matching T-shirts that said: "Our Planet. Theirs Too."
Video footage of the event (credit: Wild Vegans)
The event in West Hollywood, commemoration the ninth National Animal Rights Day, was attended by tens of thousands of people in 32 cities around the world including New York, London, Paris, Frankfurt, Copenhagen, and Mumbai among others.
Phoenix and Mara lead the Funeral March down Beverly Blvd as they were followed by thousands of other activsts carrying dead pigs, chickens, lambs, and other farm animals.
After the march, participants gathered at the north Lawn of Pan Pacific Park, for a short Memorial Service for the animals with music and speeches.