Blog: the venomous primate

Fitting with the theme of venomous creatures from October's 'Vital Venoms and Practical Poisons' campaign, Anna Nekaris, Professor in Primate Conservation and Director of the Little Fireface Project, talks us through one of the world's most overlooked group of venomous animals: 

Venomous animals conjure up images of slithering snakes, spiky scorpions, or even a wobbly jellyfish, but several mammals are surprisingly venomous too! Included in their ranks are Eurasian water shrews, American short-tailed shrews and the solenodon. In the last decade, the vampire bats joined their ranks. Perhaps the best known of the venomous mammals is the platypus, the males of which use a venomous spur to fend off other rival males. This within-species competition is one of the rarest uses of venom in the animal world and is also the function of venom in the mammal I study. This unlikely contender is not only incredibly cute, but it is also a close relative to humans – the slow loris – a nocturnal primate, nine species of which are found from Northeast India to the Philippines.

For ten years now, I have been leading a study of the function of venom in the Javan slow loris on the Indonesian island of Java. When we started our work, we assumed that lorises might use their venom to fend off predators or perhaps to eat their prey. But tests we did in the wild showed it was definitely neither of these. Certainly lorises who groom themselves have fewer parasites, and the venom may play a role in reducing parasites like fleas and ticks. But a decade of horrible head wounds, lost digits, and nasty fights even leading to the deaths of rivals has allowed us to unquestionably state that this is the main function of their venom. The venom of slow lorises is also peculiar in that, like their relatives the lemurs, they exude an oil from their arm gland above the elbow. When they lick this and it combines with saliva in their mouth, it becomes toxic and can be injected with their teeth. All lemurs, lorises and bushbabys have a toothcomb. Lorises also use theirs to eat their preferred food – tree gums! – and to groom their friends and family. But that same toothcomb can become a deadly weapon, leading to gruesome wounds.

Knowledge of venom is not only important for understanding the ecology of wild lorises, but also for their conservation. The Javan slow loris is Critically Endangered. If habitat loss was not enough, their cute appearance has made them one of the most frequently traded pets in Indonesia; other species of slow loris are traded as well. In order to make them “safe” for human owners, traders frequently cut out their front teeth with pliers or nail clippers. As you can imagine, life without that amazing slow loris Swiss army knife affects their ability to eat, be social and to defend themselves. Plenty of slow lorises are still traded illegally and social media sites such as TikTok and Instagram still portray them as cute pets. The more knowledge we have of their venom can be a powerful tool to help stop this trade.
 

Anna Nekaris

Little Fireface Project, Cipaganti, West Java Indonesia

Oxford Brookes University, Oxford UK

All blogs reflect the views of their author and are not a reflection of BIAZA's positions.