Unseen engineers have been secretly shaping life on Earth, says new research

Recently published studies suggest insects play a much larger role in seed dispersal than previously thought.

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Plants produce fleshy, juicy, sweet fruit with seeds inside so that birds and fruit-eating mammals, from toucans to fruit bats to orangutans, are lured into taking a bite. Then, these animals fly or roam far and wide and, once they've digested their meal, excrete the seeds together with the rest of their waste.

In doing so, these hungry animals help plants, which can't move, to travel and disperse their seeds across a wider range.

This is at the base of how hundreds of ecosystems work and has been since the dawn of time. However, a growing body of research is starting to suggest that mammals and birds are far from the only ones shaping how seeds travel and spread plant life to new parts of the world. Tiny insects and invertebrates play a crucial role, too.

Ants are perhaps the most well-known seed-dispersing insects. But the seeds they spread aren't from fruit.

They spread seeds from particular plants that have special, ant-friendly oil bodies attached to the seed, known as elaiosomes. The ants carry the seed to their nest, eat the elaiosome and discard the seed, either by carrying it to the surface or placing it into 'rubbish piles' deep underground, according to Prof Ellen Simms, an integrative biologist at the University of California, Berkeley.