The gentle giant

I blame Belfast Zoo for my lemur addiction. It’s a rather super place with a remarkable success rate in breeding rare species. If you visit, you’ll find that part of the tour allows you to walk through a beautiful large grove where lemurs roam freely. They’ll run out in front of you with their adorable little babies on their backs, and sometimes they may sit observing you with a cheeky little look, and maybe, if you’re lucky, one may whizz past you close enough to feel their soft, almost rabbit-like fur brush against your legs. A lot of those ring-tail lemurs have the attitude of the party-loving King Julien of the Madagascar animated films!

The four extant families of modern lemurs (Lemuridae, Cheirogaleidae, Lepilemuridae, and Daubentoniidae) all share an ancient lineage. Although fossil lemurs are very rare, molecular phylogenetic studies suggest that lemurs split from lorises around 65 million years ago.

A beautiful lemur, Lepilemur sahamalazensis by Lepilemur_sahamalazensis (Image from here)

These unique creatures only exist in Madagascar, and no-one is entirely sure why. This large island has been isolated for over 88 million years. Many have hypothesised their ancestors, like  groovy King Julien liked to ‘move it –move it’ and crossed the 400 km from Africa to the exotic island via temporary landbridges thrown up by seismic activity, then got cut off when they subsided. Others have considered the creatures as having originated in India, and accidentally ‘rafted’ across the oceans on plant material, all through primate curiosity! As no truly ancient fossils have yet been discovered on the island of Madagascar, the paleontological record relies on subfossils dating between 8kya and 500 years ago.

It’s within these remarkably recent subfossils that evidence was found of a very different kind of lemur than our rather cute, tiny, furry ring-tailed pals in modern zoos – the giant lemurs, or Palaeopropithecidae.  There are presently four known genera within this clade, although new subfossils could very well turn up within excavations- there is much yet to be discovered. The biggest of the Palaeopropithecidae was the gorilla-sized Archaeoindris fontoynontii: the biggest lemur ever discovered, and still an exciting, cuddly and massive enigma.

There’s so much we have to speculate about the amazing A. fontoynontii, as unbelievably, there has only ever been one complete skull found, during French palaeontologist Charles Lamberton’s 1930s excavations at Ampasambazimba, Madagascar. No subfossils have yet been found anywhere else on the island, so it is assumed there were never large populations of this creature. That precious skull is now kept at the University of Antananarivo.  However, fragments of mandible and long bones had been found during the first decade of the 20^th century by the scholarly missionary and palaeontogist, Herbert Standing, so the quest was on to discover more about this huge, mysterious lemur.

A cast of the only complete skull of the giant lemur, Archaeoindris fontoynontii. Cast on display at the Museum National d’Histoire Naturelle de Paris.  (Image by wiki member Ghedo, from here)

Many errors were made with regards to the phylogeny of Archaeoindris fontoynontii, and it really wasn’t until 1988, with revolutionary work carried out by Martine Vuillaume-Randriamanantena of the University of Antananarivo, that it was understood which giant lemur was related to which! This work was developed by Ludovic Orlando’s team in 2007, working on ancient DNA. We now know that A. fontoynontii was related to other, slightly smaller giant lemurs Palaeopropithecus, and Babakotia.

The huge, but cuddly, A. fontoynontii takes its name from an extant relative, the cute little Indri lemur. This small lemur is a relative of the giant, but the name also gives a little nod to a Madagascar academic, Antoine Fontoynont who supervised Standing and his team during excavations in 1909.

Imagine, if you will, this unique and rare primate slowly and masterfully striding out across the forested landscape – although it’s also possible it was also capable of some slow, purposeful swinging should the sturdiness of branch allow it! It’s been estimated it weighed over 160kg, with a wide face, and rather peculiar protrusions close to its nostrils (some feature evolved through sexual selection perhaps?). Despite its rather intimidating size and obvious power,  the teeth of this gentle giant  indicate that it loved nothing better than to munch away on foliage, which it’s reckoned it sourced mostly from  the upper branches of trees rather than ground-level shrubbery. If it did manage the odd stately tree-swing, it must have been a pretty impressive and slightly unnerving sight.

Madagascar is not just an aesthetically beautiful island, but is a unique place due to its millions of years of isolation resulting in incredible variations in biodiversity and ecosystems, geographical features and climates within a relatively small area. Dental analysis on the limited amount of specimens available has shown that the feeding areas of A. fontynontii decreased as time passed, possibly suggesting a very direct impact from human land-management activities. Human colonisation has not been limited to one period of prehistory, although there are long periods of time for which we know almost nothing. This has been where palaeoecology has come to the rescue, providing a framework of land-use change. Established dates show definite human agricultural activity during the 5^th century BC, with Cannabis and Humulus (Hops) visible in palynology assemblages. However, there’s a number of archaeological sites showing evidence of burning through the Holocene period 4-10kya, although this decreased considerably from 3kya. It’s very possible the burning was part of a landnám phase of forest clearance for settlements, agricultural activity and even sacred, ritual spaces.

None of this would have boded well for already rare creatures whose size required expanses of forest to inhabit for safety and feeding. There’s a dramatic decline in megafauna c.  AD 230–410 (calibrated), which coincides with a drastic decline in Sporormiella spp. fungi, which thrives on decaying organic matter and (there’s no polite way to put this) animal poo- the sorts of things you’d find in a luscious forest rich in biodiversity. The decline of this fungus is followed by another wave of burning.  As the forests were steadily cleared, the death knell of all of the giant lemurs had just tolled. As earlier prehistoric pollen records show that really severe climate changes of the past had little or no discernible effect on megafaunal extinction. Around 2000 BC the southwest of the island was very dry, while woodlands increased in the centre of the island (where A. fontynontii lived, oddly enough) because of higher moisture and lower temperatures.

The fossil skull of another extinct lemur, Palaeopropithicus maximus taken at the Museum National d’Histoire Naturelle de Paris.. There is evidence that humans hunted some lemur species. Image by wiki member Ghedoghedo (Image from here)

Perhaps the most sinister archaeological evidence is the discovery of Palaeopropithecus bones with very clear butchery marks on them. As Palaeopropithicus was a smaller ‘relative’ of Archaeoindris, it would seem fairly likely humans also hunted and consumed the mightiest of the giant lemurs. The radiocarbon dates for the Archaeoindris bones we have are incredibly late – even calibrated they are between the 5^th and 1^st centuries BC, at a time when land cultivation was most certainly occurring island-wide. The blame for the extinction of these creatures must be placed firmly with Homo sapiens.

A sad story, but there is a strange footnote to add. There is a crazy chance that there may be actual, recorded eye-witness accounts of the last of the giant lemurs. Flacourt recorded in his travelogue of 1661 that villagers knew of a rare and solitary creature they called the tretretre, which was, described as being as “large as a two year old calf, with round head and human face, but both fore and hind feet are like a monkeys. It has frizzy fur and a short tail, and ears like a man’s.”  However, there is the ominous ending in this recollection that the tretretre was always alone.

Written by Rena Maguire (@JustRena)

Further Reading:

Blanco, M. B., Dausmann, K. H., Ranaivoarisoa, J. F. & Yoder, A. D., (2013), ‘Underground hibernation in a primate’. Scientific Reports. 3. pp.1768.1-4. [Full article]

Burney, D. A; et al. (2004), ‘ A chronology for late prehistoric Madagascar’ Journal of Human Evolution. 47. pp.25- 63. [Full article]

Burney, D. A., Robinson, G. S.  & Burney, L. P., (2003), ‘Sporormiella and the late Holocene extinctions in Madagascar’. Proceedings of the National Academy of Sciences, USA. 100 pp.10800-10805. [Full article]

Burney, D. A., et al. (1997), ‘Environmental change, extinction and human activity: evidence from caves in NW Madagascar’. Journal of Biogeography. 24. pp.755-767. [Abstract only]

Crowley, B. E. (2010), ‘A refined chronology of prehistoric Madagascar and the demise of its megafauna’. Quaternary Science Reviews. 29. pp.2591-2603. [Full article]

Flacourt, É. (1661). Histoire de la Grande Ile de Madagascar. Paris: IDALCO

Godfrey, L. R., et al. (2012), ‘Dental topography indicates ecological contraction of lemur communities’. American Journal of Physical Anthropology. 148(2). pp.215-227. [Abstract only]

Godfrey, L. R., & Irwin, M. T. (2007), ‘The evolution of extinction risk: Past and present anthropogenic impacts on the primate communities of Madagascar’. Folia Primatologica. 78 (5). pp.405-419. [Full article]

Godfrey, L. R., & Jungers, W. L. (2003). ‘The extinct sloth lemurs of Madagascar’. Evolutionary Anthropology: Issues, News, and Reviews. 12 (6). pp.252-263. [Abstract only]

Jungers, W. L. (1990), ‘Problems and methods in reconstructing body size in fossil primates. Body size in mammalian paleobiology: estimation and biological implications’.  Cambridge: Cambridge University Press. [Book]

Karanth, K. P., et al. (2005). ‘Ancient DNA from giant extinct lemurs confirms single origin of Malagasy primates’. Proceedings of the National Academy of Sciences of the USA. 102 (14). pp.5090-5095. [Full article]

Krause, D. W., (2010), ‘Washed up in Madagascar’. Nature. 463. pp.613-614. [Abstract only]

Muldoon, K. M., et al. (2012), ‘ Early Holocene fauna from a new subfossil site: A first assessment from Christmas River, south central Madagascar’. Madagascar: Conservation & Development. 7 (1). pp.23-29. [Full article]

Muldoon, K. M. and Goodman, S. M., (2010). ‘Ecological biogeography of Malagasy non-volant mammals: community structure is correlated with habitat’. Journal of Biogeography. 37 (6). pp.1144-1159. [Abstract only]

Muldoon, K. M., (2010), ‘Paleoenvironment of Ankilitelo Cave (late Holocene, southwestern Madagascar): implications for the extinction of giant lemurs’. Journal of Human Evolution. 58. pp.338-352. [Abstract only]

Orlando, L., et al. (2008),  ‘DNA from extinct giant lemurs links archaeolemurids to extant indriids’. BMC Evolutionary Biology. 8 (1). pp.121. [Full article]

Simpson, G. G., (1940), ‘Mammals and land bridges’. Journal of the Washington Academy of Sciences. 30. pp.137-163. [Full article]

Standing, H. F. (1909),  “Subfossiles provenant des fouilles d’Ampasambazimba”. Bulletin de l’Académie Malgache. 6. pp.9-11

Stankiewicz, J., Thiart, C., Nasters, J.C. and de Wit, M.J., (2006), ‘Did lemurs have sweepstakes tickets? An exploration of Simpson’s model for the colonization of Madagascar by mammals’. Journal of Biogeography. 33. pp.221-235. [Full article]

Vuillaume-Randriamanantena, M. (1988), ‘ The taxonomic attributions of giant subfossil lemur bones from Ampasambazimba: Archaeoindris and Lemuridotherium’. Journal of Human Evolution. 17 (4). pp.379-391. [Full article]