If Pokémon Go players think catching 151 different pocket monsters on their smartphones is tough, imagine trying to collect more than 15,000.
That’s what botanists studying the trees of the Amazon rain forest have been attempting for more than 300 years. So far, intrepid explorers have found a total of 11,676 different tree species, a new study reports.
After analyzing more than 500,000 digitized samples taken of fruits, flowers and leaves, a team of ecologists has compiled what they call the first list of every known tree type in the Amazon. They published their findings Wednesday in the journal Scientific Reports.
“Before this paper we didn’t have a list of Amazonian trees,” said Nigel Pitman, a tropical forest ecologist at the Field Museum in Chicago, and an author of the study. “With this list we are answering ‘How many species have been found?’ and ‘What are they?’”
Dr. Pitman and his team combed through hundreds of thousands of digital records from museums around the world to create their catalog. The oldest samples were collected in 1707 and the most recent were obtained in 2015.
“What cracks me up about this paper,” Dr. Pitman said, “is that it’s a bunch of ecologists who got impatient and said ‘Let’s see if we can make a quick checklist and see what we get.’”
He admits that his catalog may not have been as meticulously put together as those constructed by taxonomists who organize organisms for a living. But that’s sort of the point, he added. The team wanted to create an index that would serve as the basis of a wiki that other researchers could critique and contribute to.
A Guide to Digitized Natural History Collections
Natural history museums around the world have been growing beyond display cases and dioramas for years, and many are digitizing their vast collections.
“This is an effort to pull together this 300-year-long research on this incredibly diverse region and convert it into a simple tool that anybody can use,” he said. “It’s the best we can do now for someone who wants to know what trees have been collected in the Amazon.”
The bonus to the team’s list, according to Hans ter Steege, a tropical forest ecologist at Naturalis Biodiversity Center in the Netherlands and lead author of the paper, is that it supports their previous, hotly debated claim that there are about 16,000 tree species in the Amazon. They arrived at that estimate in 2013 after investigating the number of rare and common tree species in a sample of 5,000 tree species, and then mathematically extrapolating the figures to the greater Amazon.
“We looked at all the databases and we found nearly 12,000 species that had been collected in the Amazon,” he said. “That’s great news — it supports our Amazon of 16,000.”
The remaining 4,000 tree species may be hiding in museum drawers that have not yet been digitized, or are still undiscovered in the Amazon. According to Dr. ter Steege it may take centuries before botanists track down all the rare species.
As for now, he said “we will certainly not catch them all.”