Scientists Are Discovering New Species Faster Than Ever — Over 16,000 a Year
A major new study finds the pace of species discovery is accelerating, not slowing, and suggests the true number of species on Earth could reach into the billions.
It has been roughly 300 years since Carl Linnaeus began the project of naming and classifying life on Earth. A University of Arizona-led study published in Science Advances now reveals that scientists are discovering new species at a faster rate than at any point in human history, with more than 16,000 species added each year.
The research analyzed the taxonomic histories of roughly 2 million species across all groups of living organisms. Its findings suggest the planet’s biodiversity may be far richer than most people imagine — potentially reaching into the billions of species.
The Discovery Rate Is Going Up, Not Down
The study directly challenges the assumption that the golden age of species discovery is behind us.
John Wiens, a professor in the University of Arizona Department of Ecology and Evolutionary Biology and senior author of the study, was blunt about the finding. “Some scientists have suggested that the pace of new species descriptions has slowed down and that this indicates that we are running out of new species to discover, but our results show the opposite. In fact, we’re finding new species at a faster rate than ever before,” he said.
Between 2015 and 2020, researchers documented an average of more than 16,000 new species per year. That included over 10,000 animals — dominated by arthropods and insects — along with 2,500 plants and 2,000 fungi.
These are not all microscopic organisms. “These thousands of newly found species each year are not just microscopic organisms, but include insects, plants, fungi and even hundreds of new vertebrates,” Wiens said. Hundreds of animals with backbones are still being discovered every single year.
The True Number of Species Could Be Staggering
Scientists have currently identified around 2.5 million species. But the study projects the true total is vastly larger.
“Right now, we know of about 2.5 million species, but the true number may be in the tens or hundreds of millions or even the low billions,” Wiens explained.
The projections for individual groups are striking. The study suggests there may be as many as 115,000 fish species, though only about 42,000 have been described so far. For amphibians, the projected total is 41,000 species, compared to just 9,000 currently known. The researchers suggested the final number of plant species could exceed half a million.
Insects present perhaps the most dramatic gap. Scientists have currently identified around 1.1 million insect species, but according to Wiens, estimates suggest the true number could be up to 6 million or even 20 million.
Molecular Tools Are Speeding Things Up
Part of the acceleration in discovery is being driven by advancing technology, particularly molecular and genetic tools.
“Right now, most new species are identified by visible traits. But as molecular tools improve, we will uncover even more cryptic species – organisms distinguishable only on a genetic level. This is especially promising for revealing more unique bacteria and fungi,” Wiens added.
Many species look identical to the eye but carry distinct genetic signatures marking them as entirely separate organisms. As those detection tools become more powerful and accessible, the pace of discovery is expected to climb even higher.
Discovery Is Outpacing Extinction
The rate at which new species are being found far outpaces the rate of extinction, which Wiens and his team calculated at approximately 10 species per year. Weighed against more than 16,000 species being documented annually, the ledger of known life on Earth is growing dramatically.
One particularly notable finding: 15% of all known species have been discovered in just the past 20 years.
Wiens himself highlighted this point. “Even though Linnaeus’ quest to identify species began 300 years ago, 15% of all known species have been discovered in just the past 20 years. So much remains unknown, and each new discovery brings us closer to understanding and protecting the incredible biodiversity of life on our planet,” he said.
Why It Matters Beyond Wonder
There are practical reasons to keep looking beyond the sheer scale of what remains unknown.
Wiens emphasized that cataloging species is the essential first step toward protecting them. “Discovering new species is important because these species can’t be protected until they’re scientifically described. Documentation is the first step in conservation – we can’t safeguard a species from extinction if we don’t know it exists,” he said.
The discovery of new species has already fueled breakthroughs in medicine and engineering. Natural products inspired by organisms include GLP-1 receptor agonists for weight loss, spider and snake venoms, and compounds from plants and fungi with potential uses in pain relief and cancer treatment.
Innovations extend beyond pharmaceuticals as well. Wiens noted that “many species have adaptations that can inspire human inventions, such as materials mimicking the ‘super-clinging’ feet that allow geckos to climb up vertical surfaces.”
What Comes Next
The research team plans to map geographic hotspots for undiscovered species and examine who is making these discoveries — questions that could help direct future conservation and research efforts to where they are needed most.
BOTTOM LINE: The age of species discovery is not winding down — it is accelerating, and the vast majority of life on this planet remains unknown, carrying potential breakthroughs in medicine, engineering, and conservation.
Production of this article included the use of AI. It was reviewed and edited by a team of content specialists.
