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Every day millions of people around the world take pictures of plants. Some photos are posted on social media, some uploaded to community science projects and some displayed in the online galleries of research institutions. With so many botanical paparazzi stalking the world’s forests and cities and backyards, it seems safe to assume that by now the Earth’s flora has been photographed many times over.
Not so, suggests a new paper published last month in the journal Nature Plants. In fact, nearly half of plants on Earth may have never been photographed in the wild.
We reached this conclusion by surveying 25 large websites that display plant photographs, ranging from social media sites like Flickr and Pl@ntNet to community science sites like iNaturalist to academic sites like Brazil’s Flora do Brasil project and the Field Museum’s Live Plant Photos gallery.
“When you tally up all the plants that are displayed on these websites,” says Dr. Tomomi Suwa, data scientist at the Field Museum and a co-author of the study, “you get a list containing tens of thousands of species. Which is really satisfying. But then you get an equally long list of species for which we can’t find a single photo.”
Our study suggests that most of the plants that haven’t been photographed yet grow in megadiverse tropical plant communities. For example, Brazil harbours more plants than any other country—almost 35,000—but some 15,000 of those have not yet been photographed.

And there’s another problem. We also discovered that no single website surveyed contained photographs of most plant species—not even Google, or the world’s Global Biodiversity Information Facility.
“We need to organize plant photos into a global online gallery where it’s easy to find them,” says Dr. Rafaela Campostrini Forzza, curator at the Rio de Janeiro Botanical Garden and a co-author of the study. “This isn’t just tidying up. We’re in the middle of a global extinction crisis, and we can’t protect endangered plants if we don’t know what they look like.”

Our study focused on the plants of the Western Hemisphere: North America (which has the best-photographed flora), South America, Central America, and the Caribbean (which has the least-photographed flora). The 31 authors are based in institutions across the United States, Brazil, Ecuador, Argentina, and Europe.

Nigel Pitman is a plant ecologist and conservationist with a keen interest in Amazonian plants, parks, peoples, and wildlife. He works at the Field Museum of Natural History, focusing on research and conservation of the plants of tropical South America. Follow him on Twitter @PitmanNigel