Nature's scaliest, most Pokémon-like mammal, the pangolin, is under serious threat from poaching.
But according to recent research, the very detail that makes these bizarre animals attractive to poachers — their scales — might also help get them off the endangered species list.
Wildlife forensic experts have figured out a way to lift fingerprints from pangolin scales. The new method uses gelatin, which — apart from the traditional dusting — is a common way that forensic scientists pick up prints from surfaces.
Paul Smith, director of the Forensic Innovation Center at the University of Portsmouth, first heard about a problem plaguing wildlife law enforcement from colleagues at the university's Wildlife Crime Unit. The unit is designed to educate students and to foster collaboration between forensic experts and wildlife crime rangers. It was where Smith first learned that there wasn't an effective method for detecting fingerprints from scales.
"I got to admit, back then, I thought, 'What's a pangolin?'" Smith tells Inverse. He and his colleagues quickly caught up to speed and began looking into the idea of using gelatin on the curious animals' scales.
Eight pangolin species live in Africa and Asia. All of them are considered threatened — their status ranging from vulnerable to critically endangered. The animals are hunted for their meat and scales and are the world's most trafficked animal. In June, Chinese officials removed pangolin scales from a list of approved ingredients used in traditional medicine in an effort to deter pangolin hunting, killing, and smuggling.
Stopping wildlife trade is also in the interest of public health — the trafficking of animals increases the risk of zoonotic disease spread. At the start of the Covid-19 outbreak, pangolins were thought to be a potential interim animal host, facilitating the spread of the novel coronavirus SARS-CoV-2 from bats to humans. Now, that theory is largely discounted, and pangolins are being studied as a potential treatment model since the animals' unique immune system prevents them from getting very sick.
The new research involved an international collaboration between United Kingdom researchers and wildlife crime rangers based in Africa and India. Smith and his colleagues describe the method in a recently published online paper that's included in the August edition of the journal Forensic Science International.
Fingerprints and beyond — Gelatin is a soft material that picks up pretty much anything left on a surface.
The material has been used in forensics for around a century, Smith says. Its basis is simple: When something touches a surface, it may leave behind an impression — perhaps in the dust, or in the form of a sweat deposit.
By pressing a sheet of gelatin onto the surface, the gel — a soft material, which can be cut to different sizes but looks similar to the underside of a mousepad — adheres to the surface and picks up those impressions. That's true whether the surface is a tabletop or a pangolin scale.
"You will see it more or less instantly," Smith explains.
Since gel picks up other substances besides fingerprints, it can give scientists additional clues into where pangolins are being traded. By lifting soil or pollen, for example, which are specific to certain regions of the world, forensic experts can detect where a pangolin scale has traveled.
For that reason, using gel is a better option than the old standby of dusting for fingerprints, Smith explains.
"When you apply powder to something, potentially, you're brushing things away," he says. "You're taking away the evidence."
It also helps that pangolins are adept at digging and burrowing, so they're likely to pick up some debris from their surroundings.
In the future, Smith says, gelatin could even be used to pick up DNA
"Gel is not only just for finger marks," Smith says. "It can potentially be used for a whole host of evidence opportunities" on scales and other items.
Keeping rangers safe — Beyond pangolin scales, method could hypothetically be used for other smooth surfaces, like ivory tusks. It's particularly useful for pangolins because scales are small enough to efficiently check for fingerprints.
Using gelatin could also help keep people safe when they are tracking down poachers. It's low-tech, easy to use, and allows wildlife rangers to quickly get in and out of a scene, Smith explains.
That's important because illegal wildlife trade is a dangerous realm — especially for those trying to stop it. A 2018 study found that more than 100 wildlife rangers died in the line of work in just one year. Of those deaths, 48 people were murdered while working.
Hearing what it's like to work on the ground in places where pangolin trade is thriving helps illuminate how science can help, Smith says. The key, he says, is to "develop methods that work — that's based on the lens of people doing the frontline investigation."
That means traveling internationally and talking to local rangers about their experiences.
"Allow the design, the development, the methods that work to come from those at the frontline," Smith says. "Those that experience it day-in, day-out. Those that know the area."
Abstract: Recent media reports document the plight of the Pangolin and its current position as “the most trafficked mammal in the world”. They are described by some as scaly anteaters as all species are covered in hard keratinous tissue in the form of overlapping scales acting as a “flexible dermal armour”. It is estimated that between 2011 and 2013, 117,000 to 234,000 pangolins were slaughtered, but the seizures may only represent as little as 10% of the true volume of pangolins being illegally traded. In this paper, methods to visualise fingermarks on Pangolin scales using gelatine lifters is presented. The gelatine lifters provide an easy to use, inexpensive but effective method to help wildlife crime rangers across Africa and Asia to disrupt the trafficking. The gelatine lifting process visualised marks producing clear ridge detail on 52% of the Pangolin scales examined, with a further 30% showing the impression Journal Pre-proof of a finger with limited ridge detail. The paper builds on an initial sociotechnical approach to establishing requirement, then it focuses on the methods and outcomes lifting fingermarks off Pangolin scales using gelatine lifters, providing an evaluation of the viability of using the lifters in practice.