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De Loys’ Ape and what to do with it

Purely because the time feels about right, I thought I’d post an excerpt from the cryptozoology-themed book that John Conway, Memo Kosemen and myself published last year – Cryptozoologicon Volume I (Conway et al.

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Purely because the time feels about right, I thought I'd post an excerpt from the cryptozoology-themed book that John Conway, Memo Kosemen and myself published last year - Cryptozoologicon Volume I (Conway et al. 2013). The book is still available for purchase here; previously featured excerpts are linked to at the bottom of this article, and note that Volume II is due to appear imminently. Anyway, to business...

A South American ‘ape’

Arguably one of the most fascinating episodes in cryptozoological history involves the alleged South American primate species Ameranthropoides loysi, proposed as a new species by anthropologist George Montandon in 1929. This large, allegedly new primate species is represented only by a single photograph, allegedly taken on the Colombian-Venezuelan border by Swiss geologist François De Loys in 1920. De Loys claimed that he and his party encountered two of these bipedal, erect-walking primates, shot one of them dead, and propped its body up on a wooden crate before taking the famous (and famously creepy) photograph so familiar from books on monsters and mysteries.


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The creature was supposedly very large (De Loys said 1.5 m tall), tailless, and with a human-like tooth count. Combined with its erect form of habitual bipedality, it was – according to De Loys – wholly different from all known South American primates (or platyrrhines), and perhaps a convergently evolved South American ‘ape’. The story has been discussed several times in the cryptozoology literature, most usefully by Heuvelmans (1995), Shuker (1991, 2008) and Urbani & Viloria (2009).

A sceptical look at De Loys' ‘ape’

Montandon’s naming of A. loysi and De Loys’ alleged discovery of it were both treated with immediate scepticism across Europe (Keith 1929). The fact that no part of the specimen had been retained was one problem. De Loys argued that the remains had either been lost due to accident, or became destroyed due to mistreatment (the skull, for example, supposedly corroded away after being used as a salt container).

This all meant that none of the supposedly unique features of the animal could be checked or confirmed. The unusual tooth count could only be confirmed by a look at the skull (and this was lost), the lack of a tail couldn’t be checked because the animal had only been photographed from the front, and the alleged large size of the animal was difficult to be confident about because the photographs did not include a human for scale. All in all, highly suspicious (there have even been claims that the photograph could not have been taken where De Loys said it had, due to discrepancies with the flora). And another problem comes from the fact that the creature featured in that famous photograph is not exactly enigmatic or truly unidentifiable: it looks exactly like the creature many people said it is… a White-fronted spider-monkey Ateles belzebuth [adjacent photo by Ewa/Ewcik65].

More insidiously, it has been argued in recent years that Montandon endorsed and required the creation of a large, vaguely human-like South American primate because – as a supporter of the then seriously regarded 'hologenesis' hypothesis – he needed a primate that could serve as an ancestor of South American humans. Hologenesis – widely regarded as racist today – was the school of thought proposing that the different racial groups of Homo sapiens did not share a single ancestry but descended independently from different branches of the primate tree. Montandon seemingly needed an ancestor for ‘red’ people (native Americans), and Ameranthropoides was used as a ‘missing link’ in their evolution.

This outrageous suggestion went mostly ignored until the 1990s when Loren Coleman and Michel Raynal drew attention to the possibility that Ameranthropoides had been specially ‘invented’ to fit this erroneous model of evolution (Coleman 1996, Coleman & Raynal 1996). Montandon was killed by the French Resistance in 1944, well known as an outspoken racist with strong ‘ethno-racial’ views (Coleman & Raynal 1996). Possible support for the idea that Ameranthropoides was an outright hoax comes from a letter penned in 1962 by Enrique Tejera, a friend of De Loys who, at one point, claimed to have seen a live Ameranthropoides. In the letter, Tejera denounced the hoax, saying that the animal photographed by De Loys was a deceased pet spider monkey that had been adopted in the jungle (Shuker 2008, Urbani & Viloria 2009).

Today, several cryptozoologists hold out hope that De Loys really did photograph something novel and special and they point to local legends of big, bipedal primates from northern South America, and to rumoured half-memories of additional photos of the 1920 carcass, as evidence that supports this view (Shuker 1991, 2008). We are confident, however, that De Loys’ famous photo shows a dead spider monkey sat on a crate, the only remarkable aspect of this story being the audacity of those who thought that they could use a dead monkey to cheat the scientific world.

A world where Ameranthropoides is real

Let’s now suppose for the purposes of this book that De Loys’ ape is a real animal. Ameranthropoides is presumably a close relative of Protopithecus, an especially large fossil platyrrhine known to have inhabited Brazil during Pleistocene times (Hartwig & Cartelle 1996). Good bipedal abilities are present in various platyrrhines and Ameranthropoides represents an extreme member of the group: the largest, most short-tailed (in fact, it is tailless) and most bipedal platyrrhine ever to have evolved. Given that the large-bodied platyrrhines known to have evolved elsewhere in the group (spider monkeys, woolly monkeys and muriquis) have long, prehensile tails, the complete absence of a tail in Ameranthropoides indicates a lengthy history of terrestrial evolution, but we are unsure as to whether the enhanced bipedal abilities of this species evolved in the trees before the animal came down to the ground, or whether its ancestors came to the ground and only then became proficient bipeds.

Platyrrhines include some of the most intelligent and adaptable of all primates. Capuchins exhibit remarkable adaptability when it comes to tool-use and problem-solving in the wild and might be similar in intelligence to chimpanzees. In view of this, the especially big Ameranthropoides is probably also especially intelligent, perhaps routinely using tools and seeming almost human-like when foraging, using weapons, and breaking into foodstuffs. We can only hope that future field observations of this rare and enigmatic giant platyrrhine will provide valuable insight into its behaviour and lifestyle.

For previous articles on the Cryptozoologicon Volume I and its contents, see...

Refs - -

Coleman, L. 1996. Debunking a racist hoax. Fortean Times 90, 42.

Coleman, L. & Raynal, M. 1996. De Loys’ photograph: a short tale of apes in green hell, spider monkeys, and Ameranthropoides loysi as tools of racism. The Anomalist 4 (Autumn), 84-93.

Conway, J., Kosemen, C. M. & Naish, D. 2013. CryptozoologiconVolumeI. Irregular Books.

Hartwig, W. C. & Cartelle, C. 1996. A complete skeleton of the giant South American primate Protopithecus. Nature 381, 307-311.

Heuvelmans, B. 1995. On the Track of Unknown Animals. Kegan Paul International, London.

Keith, A. 1929. The alleged discovery of an anthropoid ape in South America. Man 29, 135-136.

Shuker, K. P. N. 1991. Extraordinary Animals Worldwide. Robert Hale, London.

Shuker, K. P. N. 2008. Extraordinary Animals Revisited. CFZ Press, Woolsery.

Urbani, B. & Viloria, A. L. 2009. Ameranthropoides loysi Montandon 1929: the History of a Primatological Fraud. Libros en Red, Buenos Aires.

Darren Naish is a science writer, technical editor and palaeozoologist (affiliated with the University of Southampton, UK). He mostly works on Cretaceous dinosaurs and pterosaurs but has an avid interest in all things tetrapod. His publications can be downloaded at darrennaish.wordpress.com. He has been blogging at Tetrapod Zoology since 2006. Check out the Tet Zoo podcast at tetzoo.com!

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