Hundreds of 'hidden' new mammal species await discovery

Image credit: Trailer for the movie Fantastic Beasts and Where to Find Them

At least hundreds of unidentified mammal species are hiding in plain sight around the world so far, according to a new study

The researchers found that most of these hidden mammals were smaller, many of which were bats, rodents, shrews and moles

Bryan Carstens, a professor of evolution, ecology and tissue biology at The Ohio State University, said part of the reason these unknown mammals are hidden from the sight of the average person is that they are mostly small and look very small.

"When you're looking at a small 10-gram animal, it's harder to notice subtle differences in their appearance than when you're looking at something the size of a human," Carstens said

"You can't tell them apart as different species unless you do a genetic analysis

The study was published March 28, 2022 in the Proceedings of the National Academy of Sciences

Small mammals like this bicolor shrew are more likely to "hide" new species than larger animals

The team, led by Ohio State graduate student Danielle Parsons, used supercomputers and machine learning techniques to analyze millions of publicly available genetic sequences from 4,310 mammal species, along with how these animals live.

This allowed them to build a predictive model to identify mammalian taxa that might contain hidden species

"Based on our analysis, a conservative estimate is that there are hundreds of species of mammals worldwide that have yet to be identified," Carstens said

The discovery itself would not surprise biologists, he said

"What we do is predict where these new species are most likely to be found," Carstens said

The results showed that the unidentified species were most likely to be found in families of small animals, such as bats and rodents

The researchers' model also predicts that hidden species are most likely to appear in species with a wider geographic range and higher variability in temperature and precipitation

Many hidden species may also appear in tropical rainforests, which is not surprising since that's where most mammal species appear

But Carstens said many unidentified species may also live in the United States

The study also shows a key reason why identifying new species is important
.
One of the newly delineated bats lives in a narrow range, right around Nevada's Great Basin, which makes its conservation particularly important
.

"This knowledge is important to people working in conservation
.
If we don't know a species exists, we can't protect it
.
Once we name something as a species, it's important in a lot of legal and other ways
.
" Carstens said
.

Based on the results of this study, Carstens estimates that about 80 percent of mammalian species worldwide have been identified
.

"It's shocking how well mammals are described compared to beetles, ants or other types of animals," he said
.

"We know more about mammals than other animals because they tend to be larger and more closely related to humans, which makes us more interested in them
.
"

Reference: "Analysis of biodiversity data suggests that mammal species are hidden in predictable places" by Danielle J.
Parsons, Tara A.
Pelletier, Jamin G.
Wieringa, Drew J.
Duckett and Bryan C.
Carstens, 28 March 2022, Proceedings of the National Academy of Sciences .

DOI: 10.
1073/pnas.
2103400119