The pangolin, a unique mammal resembling a mix between an aardvark and an armadillo, holds many mysteries that scientists have yet to unravel. In a recent paper published in the journal Chromosome Research, UCLA researcher Jen Tinsman uncovered a “scientific surprise” that further highlights the peculiarity of these creatures.
The study revealed that the female white-bellied pangolin possesses 114 chromosomes, a count surpassed only by the Bolivian bamboo rat with 118 chromosomes. This number is significantly higher than that of humans, who have 46 chromosomes. In contrast, other pangolin species exhibit more typical chromosome numbers ranging from 36 to 42.
Additionally, the researchers identified another genetic anomaly. Male white-bellied pangolins possess a different number of chromosomes, specifically 113, compared to their female counterparts. This departure from the norm, where males and females typically share the same chromosome count, adds to the uniqueness of these animals.
Tinsman, a UCLA research fellow and co-author of the study, emphasized the extraordinary nature of pangolins, stating that they occupy a distinct position in the animal kingdom. Pangolins’ closest relatives include cats and rhinoceroses, and they form their own order and family.
The research, a collaborative effort involving UCLA and several other universities worldwide, as well as zoos and research organizations, aimed to provide genomic information about pangolins to support conservation initiatives. All four pangolin species face the threat of extinction.
Pangolins remain enigmatic due to the challenges associated with studying them. They do not thrive in captivity, making successful housing in zoos a rarity. In the wild, pangolins prove elusive, and the conventional monitoring techniques used for other species often fail with these animals as they can dislodge radio tags by rubbing against trees.
However, researchers have managed to gather some knowledge about pangolins. They are known to dig and employ their long tongues to consume ants, termites, and other insects. While some species, like the white-bellied pangolin, reside in trees, clinging to trunks and branches, others inhabit burrows. When threatened, pangolins curl up into a protective ball, although lions have been observed batting them around, unsure of what else to do with them.
The white-bellied pangolin is relatively small, weighing around three to four pounds and measuring less than a foot long. In contrast, certain ground-dwelling pangolins can reach weights of 80 to 90 pounds, comparable to the size of a large dog.
In addition to its scientific significance, the recent research has provided a valuable genetic resource to aid conservation efforts, particularly in combating the rampant poaching that has led to the endangered status of pangolins. These animals are targeted for their scales, which are illegally sold on international markets for use in traditional medicine, with demand spanning from Nigeria to China. Pangolins are also hunted for their meat, either locally as bush meat or as exotic delicacies in distant regions, where they can fetch high prices exceeding $1,000.
The findings from the genetic study can help identify the species of pangolins that serve as sources for these illicit products. Furthermore, the information can assist conservationists and researchers in understanding genetic variations within a species that occupies a habitat spanning 6 million square kilometers (2.3 million square miles) across 23 countries.
The understanding of chromosomes and gene structure holds significant importance for conservation efforts. It can influence population management decisions, as significant genetic differences between two groups may warrant distinct management approaches, as highlighted by Ryan Harrigan, an adjunct professor at the UCLA Center for Tropical Research and co-author of the paper.
The research not only serves the purpose of saving an endangered species but also contributes to fundamental scientific knowledge. UCLA evolutionary biologist Tom Smith, also a co-author, describes the study as a prime example of how conservation-focused research can advance scientific understanding.
Furthermore, as conservation technologies and methods continue to evolve, the research findings are likely to have practical applications in the future. With the development and refinement of technologies like artificial intelligence and emerging conservation methods such as environmental DNA (eDNA), the new discoveries regarding pangolins’ genetics can prove especially valuable.
The study also aligns with the broader mission of the Congo Basin Institute, a collaboration between UCLA and the International Institute of Tropical Agriculture, aimed at tracking and mapping pangolin poaching. The institute, with co-director Tom Smith, is based in Yaoundé, Cameroon, and operates two rainforest field stations.
It is disheartening for Smith to witness the endangerment of such a delightful creature and emphasizes the need for further genomic research to conserve other pangolin species.