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What the sources say

Bornean OrangutanPongo pygmaeus

Every figure, record and mechanism on the Bornean Orangutan profile was written from a source, and this is the working table behind it: 63 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Ancrenaz et al. 2024

Ancrenaz et al. (2024). Pongo pygmaeus. The IUCN Red List of Threatened Species 2024: e.T17975A259043172.

The page saysBornean orangutans are Critically Endangered
The source saysCritically Endangered (CR)

Source
02

Animal Diversity Web, University of Michigan

Pongo pygmaeus (Bornean orangutan). Animal Diversity Web, University of Michigan.

The page sayslong arms for the canopy
The source saysBornean orangutans have orange-red hair and long arms, which are advantageous for traveling through the canopy.
The page sayshands and feet that both grip
The source saysBornean orangutans grasp with both their feet and hands, which suites their arboreal life.
The page saysPrimary lowland rainforest, peat swamp forest, and dipterocarp forest on Borneo
The source saysThey generally live in the old growth forests ranging from the lowland swampy areas to the dipterocarp forests. The peat swamps and flood-prone dipterocarp forests produce more fruit than the dry dipertocarp forests ... Bornean orangutans inhabit the primary tropical rainforest and secondary forest at lower elevations
The page saysLong arms that help it travel through the canopy
The source saysBornean orangutans have orange-red hair and long arms, which are advantageous for traveling through the canopy.
The page sayshands and feet that can both grasp
The source saysBornean orangutans grasp with both their feet and hands, which suites their arboreal life.
The page saysBornean orangutans rarely come down to the forest floor
The source saysBornean orangutans are arboreal and rarely descend to the ground.
The page saysrather than on their knuckles
The source saysWhen walking quadrupedally, they walk on their fists rather than their knuckles, unlike other great apes.
The page saysA Bornean orangutan cannot swim, so rivers and other waterways box in where it can travel
The source saysBornean orangutans cannot swim which make rivers and other water sources impassable boundaries, limiting their range.Note: "so" is the source's own link ("which make")
The page saysa Bornean orangutan's nest platform sits 12 to 18 meters (40 to 60 feet) off the ground
The source saysBornean orangutans sleep in nest platforms made of vegetation 40 to 60 feet off the ground.Note: 40 to 60 feet converts to 12.2 to 18.3 meters
The page saysTwo Kinds of Grown Male
The source saysBornean orangutans exhibit bimaturism, or two different forms of mature males.
The page saysAdult male Bornean orangutans average about 87 kilograms (192 pounds)
The source saysmales having an average height and weight of 970 mm and 87 kg respectivelyNote: 87 kg converts to 192 lb (ADW's own table: 191.63 lb). Within NZP's current wild adult male range for orangutans, 77 to 100 kg, so the two agree
The page saysfemales about 37 kilograms (82 pounds)
The source saysfemales averaging 780 mm and 37 kg, respectivelyNote: 37 kg converts to 82 lb. Within NZP's current wild adult female range for orangutans, 36 to 54 kg
The page saysMales come in two forms: flanged males with wide cheek pads, and unflanged males that are the same size as females and look much like them
The source saysMales also develop large cheek pads known as flanges ... These two types of males are denoted as being either flanged and unflanged. ... Unflanged males look much more like the females as they are the same size
The page saysMales aged 8 to 15 are generally unflanged and become flanged between 15 and 20
The source saysMales between 8 and 15 years of age are generally unflanged and become flanged between 15 and 20.
The page saysBoth kinds of male father offspring
The source saysBoth types of adult male orangutans reproduce in the population.
The page saysunflanged males that hear it flee the area
The source sayswhen unflanged males hear long-calls they flee the area
The page saysGardeners of the Forest
The source saysBornean orangutans play such a crucial role in seed dispersal that they have been given the title "gardeners of the forest".
The page saysBornean orangutans have been recorded eating more than 500 plant species
The source saysBornean orangutans have been documented eating more than 500 plant species as part of their diet.
The page saysfruit makes up more than 60 percent of their diet
The source saysFruits make up more than 60% of their total dietary intake
The page saysThat makes them "gardeners of the forest," spreading seeds, especially large ones that smaller animals cannot disperse
The source saysSince fruits make up more than 60% the Bornean orangutan diet, they play a vital role in seed dispersal, especially for the larger seeds which cannot be dispersed by smaller animals. Bornean orangutans play such a crucial role in seed dispersal that they have been given the title "gardeners of the forest".
The page saysThe Bornean orangutan cannot swim, so rivers and other waterways limit where it can travel
The source saysBornean orangutans cannot swim which make rivers and other water sources impassable boundaries, limiting their range.Note: "so" is the source's own link ("which make")
The page saysA Bornean orangutan's nest platform, made of vegetation, sits 12 to 18 meters (40 to 60 feet) off the ground
The source saysBornean orangutans sleep in nest platforms made of vegetation 40 to 60 feet off the ground.Note: 40 to 60 feet converts to 12.2 to 18.3 meters
The page saysThe pads, called flanges, grow on some adult males
The source saysMales also develop large cheek pads known as flanges ... Bornean orangutans exhibit bimaturism, or two different forms of mature males. These two types of males are denoted as being either flanged and unflanged.
The page sayswhere they generally inhabit swampy and hilly tropical rainforests
The source saysgenerally inhabits swampy and hilly tropical rainforests

Source
03

San Diego Zoo Wildlife Alliance

Orangutan. San Diego Zoo Wildlife Alliance.

The page saysBorneo's biggest mammal in the trees
The source saysThese shaggy red apes are the largest arboreal mammal and the only great apes found in Asia.Note: The quote ranks orangutans, all three species. The Bornean orangutan is the only orangutan on Borneo (SDZoo: "Bornean orangutan: Native to the island of Borneo"), so the rank is narrowed to Borneo rather than claimed for the species worldwide; "mammal" is kept
The page saysWild figs, durian, and other forest fruit
The source saysOrangutans eat lots of ripe fruits ... Figs, along with fruit of the durian tree, are most common.
The page saysleaves, bark, insects, bird eggs, and honey when fruit is scarce
The source saysWhen fruits are scarce, they eat leaves, flowers, bark, honey, termites, ants and other insects, and even bird eggs.
The page saysAn orangutan's arms stretch out longer than its body, more than 2 meters (7 feet) from fingertip to fingertip
The source saysTheir arms stretch out longer than their bodies—measuring over 7 feet (2 meters) from fingertip to fingertip.
The page saysOrangutans also use leafy branches to shelter from rain and sun, and sometimes drape large leaves over themselves like a poncho
The source saysOrangutans also use leafy branches to shelter themselves from rain and sun, and sometimes they drape large leaves over themselves like a poncho!
The page saysOrangutan males average 136 centimeters (54 inches) in height and females 114 centimeters (45 inches)
The source saysHeight: Females, average 45 inches (114 centimeters); males, average 54 inches (136 centimeters)Note: San Diego Zoo's page covers all three orangutan species, so the figure is stated for orangutans, not as Bornean. ADW (2013) gives Bornean average heights of 970 mm and 780 mm, which disagree; the current page wins (docs/fact-check.md, Check the date).
The page saysWhen males fight, they charge at each other and break branches, and if that doesn't scare one away, they grab and bite each other's cheek pads or ears until one gives up and runs away
The source saysWhen males fight, they charge at each other and break branches. If that doesn't scare one of them away, they grab and bite each other on the cheek pads or ears until one of them gives up and runs away!
The page saysOrangutan diets center on wild figs, durian, and other forest fruit
The source saysOrangutans eat lots of ripe fruits ... Figs, along with fruit of the durian tree, are most common.
The page saysbacked up by leaves, bark, insects, bird eggs, and honey when fruit runs short
The source saysWhen fruits are scarce, they eat leaves, flowers, bark, honey, termites, ants and other insects, and even bird eggs.
The page saysTheir arms stretch out longer than their bodies, measuring more than 2 meters (7 feet) from fingertip to fingertip
The source saysTheir arms stretch out longer than their bodies—measuring over 7 feet (2 meters) from fingertip to fingertip.
The page saysOrangutans also shelter from rain and sun with leafy branches, and sometimes drape large leaves over themselves like a poncho
The source saysOrangutans also use leafy branches to shelter themselves from rain and sun, and sometimes they drape large leaves over themselves like a poncho!
The page saysWhen males fight, they charge and break branches, and if that doesn't scare one away, they grab and bite each other's cheek pads or ears until one gives up
The source saysWhen males fight, they charge at each other and break branches. If that doesn't scare one of them away, they grab and bite each other on the cheek pads or ears until one of them gives up and runs away!

Source
04

Smithsonian's National Zoo and Conservation Biology Institute

Orangutan. Smithsonian's National Zoo and Conservation Biology Institute.

The page saysa long call that can be heard a kilometer or more away
The source saysIt can be heard a kilometer or more away (more than half a mile).Note: NZP speaks of orangutans; ADW's Bornean account says "The long-call can be heard from several kilometers away in the right conditions", so the lower figure holds for this species
The page saysfor an ape that normally moves cautiously, climbing and walking through large trees to spread its weight
The source saysOrangutans can brachiate — swing hand over hand — but they normally move cautiously through large trees by climbing and walking. This allows them to distribute their weight among the branches.Note: vibe.reason; the words before "for" describe the track
The page saysBuilt for Life in the Trees
The source saysOrangutans are the largest arboreal mammals and are very well adapted to life in the trees
The page saysOrangutans are the largest arboreal mammals
The source saysOrangutans are the largest arboreal mammals and are very well adapted to life in the trees
The page saysit has long curved fingers and toes for grasping
The source saysThey have grasping hands and feet with long curved fingers and toes.
The page saysIts hands make it graceful and swift when swinging but slow and awkward on the ground
The source saysOrangutans' hands make them graceful and swift while swinging, but it makes walking on the ground very slow and awkward.
The page saysOrangutans can swing hand over hand, but they normally move cautiously, climbing and walking through large trees to spread their weight across the branches
The source saysOrangutans can brachiate — swing hand over hand — but they normally move cautiously through large trees by climbing and walking. This allows them to distribute their weight among the branches.
The page saysOn the ground, they use all four limbs, supporting themselves on the sides of clenched fists
The source saysWhen on the ground, they use all four limbs, supporting themselves on the sides of clenched fists
The page saysOrangutans usually build a fresh nest each night, though they sometimes rebuild an old one
The source saysThey usually build and sleep in a fresh nest each night, but they will sometimes re-enter or rebuild an older nest.
The page says"Orangutan" means "person of the forest" in the Indonesian and Malaysian languages
The source saysOrangutan means "person of the forest" in the Indonesian and Malaysian languages.
The page saysthe presence of a fully mature dominant male may suppress another male's pads, and in some cases a wild male may never develop them
The source saysThe presence of a fully mature dominant male may suppress secondary sexual characteristics (long hair, face pads, beards and enlarged throat sacs) in other less dominant males, and, in some cases, a wild male orangutan may never develop cheek pads.
The page saysA male Bornean orangutan's median life expectancy is about 27 years
The source saysThe median life expectancy for male Bornean orangutans is about 27 years
The page saysthere is not enough data to give one for females
The source saysThere is not enough available data on the life expectancy of female Bornean orangutans.
The page saysCheek Pads and the Long Call
The source sayslarge cheek pads, which demonstrate genetic fitness and amplify their long calls.Note: "typically" in the source qualifies whether males develop pads; a flanged male has them by definition
The page saysA Face Built to Be Heard
The source sayslarge cheek pads, which demonstrate genetic fitness and amplify their long calls.Note: "typically" in the source qualifies whether males develop pads; a flanged male has them by definition
The page saysA flanged male's cheek pads amplify his loud, deep long call
The source sayslarge cheek pads, which demonstrate genetic fitness and amplify their long calls. ... a loud, deep long call used typically by males for long-distance communication.Note: "typically" in the source qualifies which sex gives the call; ADW: the long-call is "performed only by flanged males"
The page sayswhich can be heard a kilometer or more away
The source saysIt can be heard a kilometer or more away (more than half a mile).Note: NZP speaks of orangutans; ADW's Bornean account says "The long-call can be heard from several kilometers away in the right conditions", so the lower figure holds for this species
The page saystheir numbers have dropped by more than half over the past 60 years
The source saysTheir population levels have dropped more than 50 percent over the past 60 years
The page saystheir habitat has shrunk by more than 80 percent in the past 20
The source saystheir habitat has declined by over 80 percent in the past 20 years.
The page saysYes. Orangutans are the largest arboreal mammals
The source saysOrangutans are the largest arboreal mammals and are very well adapted to life in the trees
The page saysthey grasp with long curved fingers and toes
The source saysThey have grasping hands and feet with long curved fingers and toes.
The page saysTheir hands make them graceful and swift while swinging but slow and awkward walking on the ground
The source saysOrangutans' hands make them graceful and swift while swinging, but it makes walking on the ground very slow and awkward.
The page saysOrangutans usually build and sleep in a fresh nest each night, but sometimes re-enter or rebuild an older nest
The source saysThey usually build and sleep in a fresh nest each night, but they will sometimes re-enter or rebuild an older nest.
The page saysThey demonstrate genetic fitness and amplify the male's long call
The source saysMales also typically develop large cheek pads, which demonstrate genetic fitness and amplify their long calls.Note: NZP's "typically" qualifies which males develop pads, and the FAQ's "grow on some adult males" carries it; the pads themselves "demonstrate genetic fitness".
The page sayswhich is audible a kilometer or more away
The source saysIt can be heard a kilometer or more away (more than half a mile).
The page saysBornean orangutans live in both the Malaysian and Indonesian parts of the island of Borneo
The source saysOrangutans live on the Indonesian island of Sumatra and in both the Malaysian and Indonesian portions of the island of Borneo.Note: NZP's page covers all orangutans; the Borneo half of its range is the Bornean orangutan's (SDZ: "Bornean orangutan: Native to the island of Borneo").

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.