One torrid afternoon, I journeyed with an Indigenous Marind woman and her family to a patch of razed forest at the edge of the plantation frontier, where workers had cleared the way for oil palm trees. Her name was Circia*. A mother of three in her late 50s, Circia was imposing, but her footsteps were gentle, almost silent when she led us across the wet soils of Merauke, a district in the Indonesian-controlled western half of New Guinea known as West Papua. The patch of former forest that we travelled toward that hot afternoon in May 2016 was a sacred site that belonged to her clan, forming part of the customary territory of the Marind peoples, which today number around 600 families. Though the Marind rely directly on the forest for their everyday livelihoods and subsistence, Circia had not journeyed here with her three children and nine grandchildren to forage or hunt. They had come to mourn.

Towering piles of felled trees surrounded us, ripped from the soil days earlier to make way for a 50,000-hectare oil palm plantation. Among and between the trees lay the bodies of plants and animals who had once inhabited this sacred place. The air was stiflingly hot and still. It was quiet, too, until a distant chainsaw ripped to life. Somewhere in the remaining patches of forest, plantation workers were clearing the way for more oil palm.

I visited Merauke between 2011 and 2019 while doing long-term ethnographic fieldwork with the Marind. I came to learn how they understood the spread of oil palm in their home of West Papua, which has been under Indonesian rule since the 1960s. But during the 18 months that I lived with Marind communities along the upper banks of the Bian River, Circia and her kin taught me something else: the arts of mourning. This was not only a mourning for people, but for trees, animals and ecosystems.

In our age of planetary unravelling, mourning has become a crucial disposition. It is one that allows us to acknowledge and grieve loss, but also to create or revive connections with more-than-human others. In that way, mourning becomes a form of resistance that pushes against human exceptionalism. It reminds us that we share the world with many other kinds of beings, and that these beings also have their own ways of grieving. But the space shared with other species is complicated. We are not just together in the same world, we are tangled up in each other’s lives. Other species live on and in us, they change us, and we change them, too: we breed them, farm them, mutate their genomes, eat them, research them, love them, and kill them. Increasingly, human action is leading to their extinction. Should we not mourn them, too? Acknowledging the relations that sustain or undermine life and death in multispecies worlds means also learning to practise ‘multispecies mourning’.

For Circia and the Marind, multispecies mourning can mobilise pain and grief, especially the grief that comes from witnessing profound ecological changes. But it’s not just a form of commemoration and remembering. Mourning resists the trivialisation of lives that aren’t human and the regimes of violence that make more-than-human deaths seem normal or natural. Mourning the deaths of plants, animals and landscapes, as the Marind do, demands that we rethink which deaths deserve grief, which deaths are morally sanctioned, and which are forgotten altogether. It invites us to consider how we might remember those who must die for us to thrive. But how exactly do you mourn a forest?