The first time I saw the proboscis monkey (Nasalis larvatus) was at the Zoo in Singapore. It takes advantage of the characteristic vegetation of the tropics, and the primate exhibit area that simulates the natural environment is exquisitely designed, and I am very happy to see nearly 40 primate species. One of the proboscis monkeys sitting on the branches became an indelible memory of the trip.
It is so strange that its growing nose is like a sweet potato hanging on the face to block the mouth, and it also covers the limelight of the small flat head, which makes people look at it and successfully becomes the most dazzling feature of the face and even the whole body.
With a little strangeness, with a little indescribable disharmony, it lowered its eyes, a little sad.
A bit of a sad encounter. Photo: Li Binbin
The last piece of paradise for the proboscis monkey
The first time I saw a proboscis monkey in the wild was in Malaysia. Taking advantage of the Tropical Biodiversity and Conservation Congress in Borneo, I wanted to go out into the wild to see what they looked like.
Ride a monkey in a tree. Pictured: Benjamint444/Wikimedia
Borneo is the only place in the world where they can be found in the wild. The world's third largest island, shared by Malaysia, Indonesia and Brunei, is one of the most biodiverse regions in Southeast Asia and even in the world. Here you can see the orangutan, see the Bornean dwarf elephant, see the Bornean horned toad... Many species, like the proboscis monkey, are endemic to Borneo.
Distribution area of proboscis monkeys. Photo: The IUCN RED LIST of THREATENED SPECIES
Proboscis monkeys live only in coastal and nearby forests, such as mangroves and dipterocarp forests. In the alluvial plains of the Kinabadan River in Sandakan, there is one of the largest proboscis monkey populations in Malaysia.
The Kinabatangan River, the second longest river in Malaysia, has been formed downstream to protect wildlife that depend on this ecosystem, with narrow reserves along both sides of the river, allowing wildlife to move freely up and down the river. Outside protected areas, however, large areas of vegetation have been cut down and replaced by oil palm forests or farmland. The reserve thus became the last promised land for wildlife.
The banks of the Kinabatan River are gradually becoming the last paradise for local wildlife. Photo: Li Binbin
Because wild animals are squeezed into this narrow range, the species richness and encounter rate are extremely high, but it has also become one of the best places to observe proboscis monkeys up close. People can sit in small boats and slowly look in the small channels on both sides of the main river, along the way, there will be long-tailed macaques, guinea-tailed macaques, silver langurs, chestnut langurs, and various hornbills, until they see the proboscis monkeys hanging on a tree slowly eating the leaves. This may be a little bit of luck in the sadness.
Mother and child in the tree. Photo: Li Binbin
Big nose, only charming
Both male and female, the nose of the proboscis monkey is long, but the nose of the male monkey will be particularly large. The newborn monkey's nose is upward, and as it ages, the nose slowly grows larger, and the color of the face changes from blue-black to adult yellow-brown.
Adult females and baby monkeys. Photo: Bernard DUPONT / Wikipedia
Maybe you will wonder, what is the use of this big nose? In fact, like the feathers of the male peacock and the mane of the male lion, it is the "deliberate" of the male in order to attract the female. A study in early 2018 formally confirmed this view.
The research team analyzed the behavior, morphology, and vocal communication of the wild proboscis monkeys and found that the larger the nose of the male proboscis monkey, the larger its weight, the larger the testicles, and the more wives in its own family.
Males with large noses not only look more attractive to the female, but also have a more attractive voice – the increase in the nasal cavity changes the vocal and resonant characteristics, and the male monkey uses the sound to show off his individual advantages and better attract the female. Same-sex competition and heterosexual choices make proboscis monkeys walk the road of enlarging their noses.
"I'm the most charming!" Photo: Li Binbin
It is not a "greasy" big belly monkey
The tall dipterocarp trees on both sides of the river bank provide an excellent living environment for the proboscis monkey. Diplodocus is a representative tree species in the tropical rainforest, which is tall and tall, and is an important shelter for various animals to hide from predators. At night, proboscis monkeys usually choose to rest on this.
Proboscis monkeys are not only masters of tree wandering, but also strong swimmers in the water, and swimming has become a common thing in their lives because they live along the coast and around rivers. In the trees, they have to avoid the attacks of cloud cats, pythons, and birds of prey, and when they get to the water, they have to avoid the predators of crocodiles. Proboscis monkeys have partial webs between their toes, which can help them swim quickly and win in danger, and it has also been observed that they can swim 20 meters underwater to avoid predators in the air.
Proboscis monkeys will constantly jump between trees, looking for young leaves to eat as much as possible to reduce the intake of toxic substances in plants. Photo: Charles J Sharp / Wikipedia
Proboscis monkeys feed mainly on young leaves and immature fruits. The stomach of the proboscis monkey is exceptionally large, and there are many bacteria that can ferment food and break down cellulose to help the proboscis monkey digest and absorb more efficiently.
The big stomach gives the proboscis monkey a kettle-like belly. Compared to some other slender primates, proboscis monkeys appear a bit "greasy."
"You're greasy!" Photo: Li Binbin
Seeing them sitting on the tree with their big bellies, the people who walked with me couldn't help but exclaim in a low voice: "Look at that female monkey, pregnant!" "In fact, a big belly does not mean it is a mother. Because of their big bellies and big noses, locals once jokingly called them "Dutch monkeys", and the proboscis monkeys are like comic book versions of Dutch colonists.
A calendar worker once bought a T-shirt with a proboscis monkey motif in Sabah, Borneo. Figure: vb
Although proboscis monkeys do not belong to the suborder Ruminant (ruminants in the usual sense, such as cattle), they can regurgitate. Repeated chewing and digestion coupled with a strong digestive tract allow proboscis monkeys to fully absorb nutrients from food and excrete less feces than other primates with similar feeding habits.
"Palace Fight Drama" in the Rainforest
Proboscis monkeys often live in small groups, usually consisting of one male, several females, and offspring. If you go to the Sabah rainforest, you may see male monkeys sitting like retired old cadres on the branches, eating leaves without hurrying, and enjoying the happiness of wives and concubines and children.
However, such good days do not often occur. Like many other polygamous species, male proboscis monkeys can be challenged at any time. The whole male group of bachelors looked at the tiger and took the opportunity to take its place. With the replacement of the "throne", infanticide may occur in the monkey group, the new king will never raise other people's children, after taking his wife for himself, he will let the mother monkey enter the state of birth and breeding with herself as soon as possible.
Domineering "micro" leaks. Photo: Charles J Sharp / Wikipedia
It is not easy to have a family, it is even more difficult to keep a family, even if there is a monkey group with wives and concubines, the members are not very stable. The study found that the female monkeys will be transferred between different monkey groups, and the reason is not clear. In a group of male and female monkeys, most of the fights occur between the females, which is a bit similar to the costume palace fight drama - to get the favor of the male monkey, the female monkey also has to "sing", it is difficult to cave candles, and sometimes it is disturbed by the juvenile monkeys.
It's becoming easier and easier for us to get used to something. Photo: Li Binbin
Over the past forty or fifty years, as large amounts of forests have been replaced by oil palms and farmland, the habitat of the proboscis monkey has become fragmented and gradually lost. In order to eat or use gastrointestinal stones (similar to beef yolk) that can be used in traditional Chinese medicine, proboscis monkeys are also hunted. As a result, the number of proboscis monkeys has decreased by more than 50%, and the IUCN Red List has assessed them as endangered.
At present, 16 protected areas have been established in the distribution area of proboscis monkeys, which delineates an important guarantee line for their survival in the wild. Outside the protected area, there is a tug-of-war between social development and species survival.
Boats carry tourists in search of "residents" in the rainforest. Photo: Li Binbin
On the Kinabadan River, we saw one boat after another carrying tourists, quietly searching for the creatures in the woods on the shore. A wooden house hidden in the woods is no ordinary resting place for vacations. At night, when people eat and communicate under the candlelight by the river, they are full of memories of the adventures of the day, whether he/she is a white-haired old man or a child who has been holding a mobile phone.
I think that perhaps more people will gradually realize that this kind of natural favor will become an asset that others cannot compete for and replace.
Original Li Binbin Species Calendar