As Seed-Dispersing Animals Vanish, So Do the Plants That Rely on Them

Over half the world’s plant species rely on animals for their seed dispersal. Many animals eat and spread seeds throughout the ecosystem, such as orangutans, who are known as “gardeners of the forest” due to the important role they play in promoting forest regeneration. The survival of plants relies on their ability to migrate to areas with suitable temperature ranges. This is particularly important in the face of accelerating climate change. So what happens when animal populations vanish?

In 2022, researchers mapped the decline of seed-dispersing animals against data on how plants respond to climate change. They found that the loss of birds and mammals has reduced the ability of animal-dispersed plants to adapt to climate change by 60%. In some regions, climate-tracking seed dispersal declined by 95%. Even though these ecosystems had lost only a few percent of their mammal and bird species.

To put it simply, if there are no animals available to eat fruits or carry away seeds and nuts, animal-dispersed plants can’t move very far. This leaves them trapped in space and unable to adapt to environmental factors, such as temperature changes. Ultimately, this could lead to the demise of their own species. The study proves that when we lose animal species, we disrupt ecological networks in ways that threaten the climate resilience of entire ecosystems.

Orangutans are a keystone species, meaning they shape the rainforest in ways that benefit thousands of other species. The presence of orangutans is a sign of a healthy, functioning rainforest. The health of rainforests, and by extension our planet, is closely linked to the survival of orangutans. This is one reason why we must protect orangutans and their rainforest homes, securing a thriving future for nature and people alike.