Discovered a new species of orangutan on the verge of extinction

A few days ago the discovery of a new species of orangutan was announced. Unfortunately, it is critically endangered. How is it possible that it has not been discovered until now? What other species of orangutans exist? What threats do they face? Can we do something to protect them? Keep reading to fin d out!

KNOWING THE ORANGUTANS

We know a lot about orangutans because of the work of Biruté Galdikas, the biggest expert in behavior of orangutans, as well as Jane Goodall is from chimpanzees and Dian Fossey was from the mountain gorillas. The orangutan is an hominid, from the same family as humans, gorillas, chimpanzees and bonobos.

Orangutans are the most distant hominids from us. Despite this, we share 97% of the DNA and the oldest ancestor between orangutans and humans lived about 14 million years ago. If you want to learn more about who the hominids are and how primates are classified, you can read this post.

Until now, two orangutan species were known: the Sumatran orangutan (Pongo abelii) and the Bornean orangutan (Pongo pygmaeus). A recent research  from November 2017 adds a new species: the Tapanuli orangutan (Pongo tapanuilensis). Since 1929 a new species of great ape had not been discovered, despite being one of the most studied groups in the world.

Bornean, Sumatran and Tapanuli male orangutans. Photo: Eric Kilby Aiwok Tim Laman 

MORPHOLOGY

The orangutan (from the Malay orang hután, ‘person from the forest’) is distinguished from the other hominids by its orange fur. It feeds, sleeps and reproduces in the trees, although it occasionally goes down to the ground to drink from the rivers. Its long arms (up to 2.2 m) and prehensile feet are perfectly adapted to the arboreal life. The flexibility of the hip and other joints allows them to adopt impossible positions for other primates.

Sumatran female orangutan with her baby. Photo: Thomas Marent

They have sexual dimorphism (difference between males and females): the males have bulging structures on the face that increase in size as the animal grows, a long beard and mustache, the hair of the arms longer and they have a bag hanging in the throat. This bag is used as an amplifier of their calls, which can be heard two kilometers away. They use it to defend their territory and attract females. The males are also larger than the females, weighing a hundred kilos or more and they measure 1,5 m (females weigh about 40 kg and measure 1.1 m in height).

Bornean male orangutans (Pongo pygmaeus) in which the mandibular bag and cheeks are shown. Source

FEEDING AND BEHAVIOUR

Orangutans are solitary and nomadic, moving through the treetops in search of fruit. They can also feed on other parts of the plants, honey and small animals such as termites, chicks, eggs and lizards.

Although they have solitary habits, their social interaction is very complex when they meet, and adolescent females can travel together for 2-3 days. Orangutans use tools and have behaviors that they learn by imitation and vary according to the region (culture).

REPRODUCTION

Females give birth in a nest at the top of the trees. After 9 months of gestation, a single baby is born and will stay close to the mother until its maturity, about 8 years. The male does not cooperate in the breeding.

One week old orangutan hitched to her mother. Photo: ARNO BURGI/AFP/Getty Images

The reproduction rate of orangutans is very low: females reach sexual maturity at 15 and give birth every 8-9 years, so they will only have about 3-4 babys throughout its life. This means that the recovery of the species is very complicated. They can live about 50-60 years.

DISTRIBUTION

It is the only great ape living in Asia, in the rainforests of the islands of Sumatra and Borneo. Its distribution is very small due to the destruction of their habitat .

Pongo, oragutan, distribution, distribution, distribution, map, map
Distribution of the 3 species of orangutan. Source: batangtoru.org

 A NEW SPECIES: THE TAPANULI

Pongo tapanuliensis. Foto: Andrew Walmsley

In 2001 scientists defined the two orangutan species known, the Sumatran and Bornean orangutans. We will not delve much into their differences to focus on the latest discovery. Mainly, Sumatran orangutans have a flatter face than Bornean’s, (which have a concave face) and their fur is thicker, longer and clearer than Bornean’s.

Pongo tapanuliensis, the new species discovered, inhabits the Batang Toru region (North of Sumatra), an ecosystem with 85% of its forest  protected. How is it possible that a new species of such large animal has not been identified until now? Traditionally, species began to be classified according to their similarities and morphological differences, but nowadays many of these species are being redefined thanks to genetic studies.

The Tapanuli population was rediscovered in 1997, but it was not until 2013 that the study of a skull give researchers some clues about notable differences with other populations. The male skull was smaller than the other population’s skulls and also the fur was more cinnamon and curly in the Tapanuli. The morphological data were not enough, so the genome of this orangutan was sequenced and compared with the populations of Sumatran and Bornean oranguntans.

It was concluded that belonged to a new species, much older than the other two: it separated from the orangutan of Sumatra 3.38 million years ago. It is the oldest evolutionary line of Pongo (see image of the previous section) and has been isolated 10,000-20,000 years from other populations of Borneo. The research was also completed with observations of behavior (the call of the males is different, they consume other species of plants) and other facts that confirm the existence of this new species (less robust skull and jaws,  different size of the molar than fossils of the Pleistocene, males with flatter cheeks covered in fine blond hair).

THREATS

Orangutans are among the most threatened species in the world. The tendency of their populations is the decrease: since 1900, more than 91% of orangutans have disappeared. According to the IUCN , they are classified as “critically endangered” the previous step to  the extinction in the wild. It is estimated that there are 14,613 individuals of Sumatran orangutan, 11,000 Bornean orangutans and there are only 800 individuals of tapanuli orangutan left. Newly discovered, it has become the most threatened species of great apes. They could disappear in a few decades: only with the death of 8 individuals per year (1%) the extinction will be a fact.

Orangutan walking through the destroyed jungle. Photo: Hardi Baktiantoro

One of the dangers they face is the illegal trade of babys as pets. To do this, the poachers kill the mother and due to the strong bond between mothers and babys, the latter suffer traumas that mark them for life. If you want to know more about the physical and psychological consequences suffered by captive apes, do not miss reasons for NOT having captive primates. In addition, prostitution and sexual abuse of female orangutans is a common practice.

However, the main threat of the orangutan is the destruction of its habitat. The destruction of the forest for logging, mining and agriculture was reduced by 60% between 1985 and 2007. The Tapanuli only occupy an area of ​​1,000 km2.

Deforestation of Borneo from 1950 to 2020. Source: UNEP / GRID-Arendal Maps and Graphics Library

Unfortunately , orangutans have become the visible face of the loss of biodiversity due to the extensive cultivation of palm Elaeis guineensis. Its oil is used worldwide in all types of products, especially in bakery, snacks and prepared food, cocoa creams and even cosmetics and agrofuels. Without forgetting the implications for the health of this low quality oil and the contamination caused by the destruction of waste during the production, the uncontrolled clearing of trees and fires of large areas of forest to grow the palm is killing the orangutans (thousands die every year), among other species such as the Sumatran tiger. Orangutans are also killed directly, either by entering the crops and occasionally to be marketed as food (bushmeat).

Orangutan with burns victim of deforestation for the palm oil industry. Photo: unknown

To learn more about the ecological crisis of Southeast Asia, do not miss this interview that we did to Joana Aragay, a biologist who lived firsthand the fires of 2015 in Borneo.

WHAT CAN YOU DO?

Anuncis

One thought on “Discovered a new species of orangutan on the verge of extinction”

Comentaris / Comentarios / Comments:

Fill in your details below or click an icon to log in:

WordPress.com Logo

Esteu comentant fent servir el compte WordPress.com. Log Out /  Canvia )

Google photo

Esteu comentant fent servir el compte Google. Log Out /  Canvia )

Twitter picture

Esteu comentant fent servir el compte Twitter. Log Out /  Canvia )

Facebook photo

Esteu comentant fent servir el compte Facebook. Log Out /  Canvia )

S'està connectant a %s

Aquest lloc utilitza Akismet per reduir els comentaris brossa. Apreneu com es processen les dades dels comentaris.