Amateur naturalists around the world are helping scientists understand the complex relationships between species through a new online platform called Who Eats Whom. Developed by an interdisciplinary team of researchers, this platform gathers data from a global citizen science initiative to create a public resource that supports ecological research and education. It draws on the popular platform iNaturalist, where users share photos, videos, and audio of plants and animals. Observers can contribute to Who Eats Whom by tagging predator and prey in their observations, helping build a detailed map of feeding relationships. So far, the project has recorded about 17,000 observations involving nearly 5,700 species, with contributions from over 2,000 people in more than 100 countries. The traditional food chain taught in schools is a simplified version of the complex interactions in nature. For example, parasites such as ticks and intestinal worms feed on predators like eagles and ermines. When these predators die, scavengers like ants clean up the remains. Some species, like rats, even prey on their own young, making them both predator and prey. Scientists have traditionally studied these interactions by observing nests or analyzing animal droppings, which can be time-consuming and unpleasant. The Who Eats Whom platform provides a more efficient and accessible way to collect this information, allowing for a broader and more diverse dataset. The Who Eats Whom platform is more than just a research tool—it also has the potential to aid conservation efforts, especially as the planet warms and ecosystems change. By collecting data over the coming years, the platform can help scientists understand how species interactions are evolving. Users can explore an interactive food web that shows predator-prey relationships, such as the hunting habits of red-tailed hawks or the feeding patterns of Western honey bees, which are also preyed upon by goldenrod crab spiders. The platform has even documented unusual interactions, like New World vultures feeding on a stillborn baby white shark found on a California beach. The project is led by researchers such as Bradley Allf, a postdoctoral researcher at Colorado State University, and Aditi Mallavarapu, an assistant professor of computer science at North Carolina State University. Their goal is to identify new predator-prey relationships and support conservation by ensuring that animals have access to the food and plants they need to survive. The research findings, titled "Who Eats Whom? A global food web derived from citizen science," will be published in the open-access journal PLOS Biology, making the data available to scientists and the public alike.