Is the tarsier a big-eyed suicidal monkey, or is that just an urban wildlife myth?
The short answer: the tarsier is a tiny nocturnal primate from the Philippines; it is not a monkey despite what half the internet calls it; it has the largest eyes relative to body size of any mammal alive; and yes, it really can kill itself when stressed. I went to Bohol to meet one to see it for myself.
I absolutely love learning about weird/quirky animals when I’m on the road. So the elusive tarsier, the tiny, nervous animal of Bohol Island certainly caught my attention when I first read about it.
I’d put the tarsier up there with the common spotted cuscus of Papua New Guinea as one of the lovable, odd animals I didn’t know existed until I started travelling and seeing them for myself.
My primate travel bucket list goal is looking strong…
I’ve seen Proboscis Monkeys and Orangutans in the wild in Borneo, been up close and personal with a silverback gorilla in the rainforests of Uganda, braved The Monkey Buffet Festival in Thailand, and although the bisexual bonobos of the DRC still evade me, I was lucky enough to meet the tarsier, making my way over to Bohol after swimming with whale sharks in the neighbouring island of Oslob.
What Is A Tarsier?
A tarsier is a small nocturnal primate found only in Southeast Asia. The Philippine tarsier, the famous one, lives on Bohol and a handful of neighbouring islands, stands around 3.5 to 6 inches tall, weighs less than a bar of soap, hunts insects at night and spends its days clinging to a tree trunk trying not to be eaten.
It is one of the strangest looking animals you will ever stand in front of. Enormous eyes, spindly fingers, a bald tail longer than its body, and a head that swivels round to look at you like something out of a horror film.
Is A Tarsier A Monkey?
No. And I say that knowing full well that the title of this post calls it one, because that is what everybody types into Google after seeing a photo of those eyes.
The tarsier is a primate, and it does share a very distant family tree with monkeys, apes and us. But it is not a monkey. It sits on its own branch, in its own family, the Tarsiidae, which split off from the rest of the primate line a very long time ago and then stayed put. The closest thing to a monkey about it is the way it looks in a photograph.
So if you came here searching for “the monkey with big eyes” or “the suicidal monkey” — you are in the right place, and you are also, technically, wrong. Everyone is. Carry on.
Why Does The Tarsier Have Such Big Eyes?
Because it hunts at night and it never evolved the reflective layer behind the eye that lets cats and other nocturnal animals squeeze more light out of the dark. No mirror in the back of the eye means the eye itself has to be enormous to gather enough light.
Each eyeball is roughly the size of its entire brain. If a human had eyes in the same proportion to their head, they would be about the size of grapefruits. That is the single fact that makes everybody who sees a tarsier photo go looking for it online, and it is also the reason the animal looks permanently horrified.
The trade-off is that those eyes are jammed solid in their sockets. It cannot look left or right the way you can. It has to turn its whole head — which, conveniently, it can do almost the whole way round.
Where Do Tarsiers Live?
Only in Southeast Asia now — the southern Philippines, parts of Indonesia including Sulawesi and Borneo. The Philippine tarsier is the one most travellers meet, and Bohol is where most people meet it.
Fascinating Facts About The Philippine Tarsier (& Other Tarsier Species!)
Apart from the obvious, like these creatures being tiny with distinctively big eyes; tarsier life is incredibly sophisticated, difficult, ruthless and often heartbreaking.
Also, the Philippine tarsier isn’t the only type of tarsier, it’s just a tad more famous, so let’s dig deep and get our geek on with these 18 fascinating facts about tarsiers!
1. Tarsiers are now only found in the Southeast Asia region
Originally discovered in North America, Europe and Asia, they now only exist in Southeast Asia.
Although the majority of them inhabit the southern islands of the Philippines (mainly Bohol), they also reside in Indonesia (Natuna Islands, Banka Islands and Banka Belitung Islands and also in parts of Indonesian Borneo).
2. The tarsier is on the verge of extinction
The main culprits are humans (engage in a sarcastic shocked tone of disbelief) clearing land for animal agriculture and illegal logging. The second offender is the house cat, living up to their well-earned reputation of being cute genocidal maniacs, hellbent on world domination.
3. The tarsier is named after its extremely long bone
… its ankle bone, called the ‘tarsus,’ which is elongated, helping them to leap relatively long distances and wrap themselves around tree branches.
4. One single tarsier eye weighs more than its brain
One tarsier eye is also bigger than its stomach.
5. The tarsier’s eyes can not rotate within their eye socket
However, their neck can rotate 360 degrees, à la The Exorcist!
6. The tarsier has the largest eyes in relation to its body out of any living mammal
Including Steve Buscemi.
7. After one day of being born, a Tarsier can climb a tree!
What did your precious little whiny, nappy-crapping self do on your first day on Planet Earth, eh?
8. The tarsier is the smallest primate in the world
Its ancestral tree is a little complicated – the tarsier is related to larger monkeys, gorillas, lemurs and even humans, but it occupies a small evolutionary branch between the strepsirrhine prosimians and the haplorrhine simians.
However, being 3.5-6 inches tall is pretty much dwarfism in the monkey world.
9. Tarsiers usually fall prey to large birds
Mainly nocturnal birds of prey, such as the owl.
10. Tarsiers are nocturnal
Probably because they spend the whole night shitting themselves regarding the prospect of being eaten by owls.
11. The tarsier suicide claim is correct (and common)
The title of this post is not a myth and sadly tarsier suicide is part and parcel of their lives. They can get very anxious, particularly in captivity.
Due to their nervous disposition, when stressed they can smash their heads off a tree until they kill themselves. The sanctuary that I went to make sure people didn’t get too close and left the flash off the camera.
12. Tarsiers are the only entirely carnivorous primates
While most apes have evolved to be omnivores with a heavy herbivorous leaning, tarsiers have evolved to eat insects, rodents, reptiles and small birds exclusively. So they are very much both the predator and the prey, a very complex life indeed for these tiny little mammals.
13. Tarsiers ‘claim’ their sexual mates during intercourse
When a male tarsier has sex with a female tarsier he leaves a ‘mating plug’ inside her vagina, a gelatinous secretion which hardens when inside, which is a way of saying to all the other horny tarsier lads; “get your filthy hands off, I saw her first!”
14. Tarsiers freak out some indigenous tribes of the Philippines
They look at the tarsier as a sign of bad luck and if they accidentally harm or scare one – they apologise to the spirits of the forest, as they believe that they will encounter bad health.
15. The Horsefield’s Tarsier stands alone (probably)
The only species of tarsier that is found in Borneo is called the ‘Horsfield’s tarsier,’ and it’s been doing biologists’ heads in for two decades! After 20 years, there is still no overall agreement on whether it’s a subspecies of tarsier, however, it’s distinctly different in appearance with a longer tail and reddish fur.
16. A tarsier can jump further than you can
That elongated ankle bone turns an animal the size of your fist into a catapult. A tarsier can launch itself several metres between tree trunks in the dark, land on a vertical branch, and do it again — dozens of times a night, without ever touching the ground. Relative to body length, that is a jump no human athlete will ever get close to.
17. Pygmy tarsiers have risen from the dead!
Originally assumed extinct for EIGHTY YEARS, primate ecologist Sharon Gursky and a team of Indonesian scientists found dead and alive pygmy tarsiers in the mountains of Sulawesi Island! The data on how many are left is sparse, but there is conclusive proof that this once-assumed dead creature has risen from the ashes and still survives in its harsh climate. Respect!
18. Tarsiers have a complex language system
Tarsiers are known to communicate in duet calls at sunrise to let others know it’s bedtime and to provide information about their pair bonding. Even more impressively, tarsiers can make ultrasonic-range sounds to warn other tarsiers of human or animal predators, which can’t be detected by the predators.
Seeing Tarsiers In Bohol
Bohol is the easiest place in the world to see a tarsier, and it is also the easiest place in the world to see one being harassed. The two are about ten minutes apart by car, so it matters where you go.
The sanctuary run by the Philippine Tarsier Foundation at Corella is the one that takes the animals seriously: a proper forest enclosure, guides who find the tarsiers for you and keep everyone back, and a flat rule about flash photography. The roadside places closer to the Loboc river are more convenient and considerably less careful — small cages, crowds, people reaching in for selfies.
How To Behave Around A Tarsier
- Flash off. Not dimmed, off. Their eyes are built for near-total darkness.
- Keep your voice down and your hands to yourself. Nobody touches a tarsier.
- Don’t crowd it, and don’t make it move. A tarsier that is shifting away from you is a tarsier under stress.
- Go in the morning if you want to see them awake-ish. They are nocturnal, so daytime visits mean watching a very tired animal clinging to a branch.
It sounds obvious. It is also exactly the behaviour that keeps fact number 11 from happening in front of you.
I hope you enjoyed these facts about the Philippine Tarsier and facts about tarsiers in general. If like me, you are lucky enough to see one for yourself please be quiet, give them space and turn off your camera flash… I’m pretty sure none of us wants a tarsier suicide weighing on our conscience!
