Monkey Lemur
   HOME

TheInfoList



OR:

The monkey lemurs or baboon lemurs (Archaeolemuridae) are a recently
extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...
family of
lemur Lemurs ( ; from Latin ) are Strepsirrhini, wet-nosed primates of the Superfamily (biology), superfamily Lemuroidea ( ), divided into 8 Family (biology), families and consisting of 15 genera and around 100 existing species. They are Endemism, ...
s known from skeletal remains from sites on Madagascar dated to 1000 to 3000 years ago. The monkey lemur family is divided into two genera, ''
Hadropithecus ''Hadropithecus'' is a medium-sized, extinct genus of lemur, or strepsirrhine primate, from Madagascar that includes a single species, ''Hadropithecus stenognathus''. Due to its rarity and lack of sufficient skeletal remains, it is one of the le ...
'' and ''
Archaeolemur ''Archaeolemur'' is an extinct genus of subfossil lemurs known from the Quaternary of Madagascar. ''Archaeolemur'' is one of the most common and well-known of the extinct giant lemurs as hundreds of its bones have been discovered in fossil deposi ...
'', and three species.


Description

Reconstructions indicate that the extinct lemurs did not climb very often and imply that they were much more adept at terrestrial living, more than any other extant strepsirrhine; they are not believed to have been exclusively terrestrial, but rather to have had a combined habitat of ground and arboreal life. A modest degree of curvature found in the remains support this idea. The genus ''
Archaeolemur ''Archaeolemur'' is an extinct genus of subfossil lemurs known from the Quaternary of Madagascar. ''Archaeolemur'' is one of the most common and well-known of the extinct giant lemurs as hundreds of its bones have been discovered in fossil deposi ...
'' consists of two known species, ''Archaeolemur edwardsi'' and ''Archaeolemur majori''. The hands and feet are very robust and large in size, but are very short, and said to be closer to the likeness of a
baboon Baboons are primates comprising the biology, genus ''Papio'', one of the 23 genera of Old World monkeys, in the family Cercopithecidae. There are six species of baboon: the hamadryas baboon, the Guinea baboon, the olive baboon, the yellow ba ...
's hand. The hind-limbs are also known to be short, which implies that the hands and feet are relatively short for the lemur's body weight. ''Archaeolemur'' is unique in the combination of post-cranial features. The overall look of the lemur was an animal with relatively short and stocky proportions which gave them limited
leaping Jumping or leaping is a form of locomotion or movement in which an organism or non-living (e.g., robotic) mechanical system propels itself through the air along a ballistic trajectory. Jumping can be distinguished from running, galloping and o ...
abilities. This indicates that ''Archaeolemur'' may have ranged over more open habitat, which is consistent with its subfossil distribution over much of Madagascar, implying that they tolerated a wide range of habitats. ''Archaeolemur'' are thought to be omnivores from the fossilized droppings of a younger individual. An imaging technique shows pictures of the mandibles, showing the bone structure of the mouth. Further studies on their enamel indicate that ''Archaeolemur'' also had the ability to exploit resources that may have been indigestible to other species, showing a great
plasticity Plasticity may refer to: Science * Plasticity (physics), in engineering and physics, the propensity of a solid material to undergo permanent deformation under load * Behavioral plasticity, change in an organism's behavior in response to exposur ...
in their dietary tracts as well. This may have helped ''Archaeolemur'' persist after the arrival of humans in Madagascar, as it was one of the last subfossil lemurs to become extinct. '' Hadropithecus stenognathus'' is the only species of the genus ''Hadropithecus'', and is commonly referred to as the "baboon lemur". The species was discovered in Madagascar in the year 1899 by
Ludwig Lorenz von Liburnau Ludwig Lorenz von Liburnau (26 August 1856 in Fiume – 9 December 1943 in St. Gilgen) was an Austrian zoologist. He was the son of naturalist Josef Roman Lorenz von Liburnau (1825–1911). In 1879 he obtained his PhD from the University of Vienn ...
, who associated the monkey lemurs with apes. Three years later, in 1902, Liburnau classified ''Hadropithecus'' as a lemur. Liburnau continued to make distinctions by reconstruction of certain skulls which reaffirmed that the monkey lemurs are a sister family to
sloth lemur The sloth lemurs (Palaeopropithecidae) comprise an extinct family of lemurs that includes four genera. The common name can be misleading, as members of Palaeopropithecidae were not closely related to sloths. This clade has been dubbed the ‘‘s ...
s. In an article analyzing the
dental microwear Dental microwear analysis is a method to infer diet and behavior in extinct animals, especially in fossil specimens. It has been used on a variety of taxa, including hominids, victoriapithecids, amphicyonids, canids, ursids, hyaenids, hyaenodont ...
of the Archaeolemuridae, some important information was discovered through fossilized teeth. This in turn helped distinguish between certain characteristics of the monkey lemurs compared to megaladapids. The two families occasionally had similar diets, observed from the overlapping textures of their dental microwear. However, the two families’ dental microwear differed at some points, indicating that archaeolemurids had a diet containing a variety of harder foods. ''H. stenognathus'' possessed similar cranial stricture and dental portions to hominins.
Carbon isotope Carbon (6C) has 14 known isotopes, from to as well as , of which only and are stable. The longest-lived radioisotope is , with a half-life of years. This is also the only carbon radioisotope found in nature, as trace quantities are formed ...
data show that they consumed
CAM Cam or CAM may refer to: Science and technology * Cam (mechanism), a mechanical linkage which translates motion * Camshaft, a shaft with a cam * Camera or webcam, a device that records images or video In computing * Computer-aided manufacturin ...
or C4 plants. The prior assumption that ''H. stenognathus'' ate C3 plants which included large seeds and hard fruits were wrong because those foods were too strong for the animal's teeth. Testing the carbon samples along southern and southwestern Madagascar where ''H. stenognathus'' once lived and was endemic to, scientists found high values of carbon isotopes tied to the C4 and CAM groups of plants. The large teeth were meant to extract the nutrients from food that needed incisional, but not tough preparation. ''H. stenognathus'' was well-suited to processing large amounts of small and/or flat, displacement-limited foods, rather than a previously thought diet of resistant, stress-limited foods. The species lived in environments in southern and southwestern Madagascar, where it is thought to have consumed
bulb In botany, a bulb is a short underground stem with fleshy leaves or leaf basesBell, A.D. 1997. ''Plant form: an illustrated guide to flowering plant morphology''. Oxford University Press, Oxford, U.K. that function as food storage organs duri ...
s and
corm Corm, bulbo-tuber, or bulbotuber is a short, vertical, swollen, underground plant stem that serves as a storage organ that some plants use to survive winter or other adverse conditions such as summer drought and heat (perennation). The word ''c ...
s of
grass Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and spe ...
es and
sedge The Cyperaceae () are a family of graminoid (grass-like), monocotyledonous flowering plants known as wikt:sedge, sedges. The family (biology), family is large; botanists have species description, described some 5,500 known species in about 90 ...
s comprising the bulk of its diet. ''H. stenognathus'' may have survived until the late
1st Millennium File:1st millennium montage.png, From top left, clockwise: Depiction of Jesus, the central figure in Christianity; The Colosseum, a landmark of the once-mighty Roman Empire; Kaaba, the Great Mosque of Mecca, the holiest site of Islam; Chess, a new ...
CE. It was driven to extinction mainly by human activity, like many other lemurs of Madagascar. However, it became extinct sooner than ''Archaeolemur'', its
sister genus In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and t ...
. The last known record of ''Hadropithecus'' was dated to around 444–772 CE. It is believed that ''Hadropithecus'' was a relatively rare lemur, based on a lower number of subfossils recorded. Similar to the sloth lemur, Hadropithecus was a large, slow, specialized lemur, that grazed and fed on seeds. ''Archaeolemur'' was more generalized, which may have allowed it to persist longer. Although it is not completely verified, ''Hadropithecuss large body and large brain, compared to other species, has led to the belief that it would have reproduced fairly slowly, making it more susceptible to extinction. The low reproductive rate goes hand in hand with
weaning Weaning is the process of gradually introducing an infant human or other mammal to what will be its adult diet while withdrawing the supply of its mother's milk. In the United Kingdom, UK, weaning primarily refers to the introduction of solid ...
age - ''Hadropithecus'' would not have weaned its young before 2.75 years of age, or even 3 years, giving it one of the slowest
life cycle Life cycle, life-cycle, or lifecycle may refer to: Science and academia *Biological life cycle, the sequence of life stages that an organism undergoes from conception to reproduction *Life-cycle hypothesis, in economics *Erikson's stages of psy ...
s of any lemur. It is believed that ''Hadropithecus'' would have not given birth more than once every other year. In addition, ''Hadropithecus'' would have spent most, if not all, of its time on the ground, making it readily available for hunting and exploitation by humans. It not only would have faced pressure from humans, but also from domestic
livestock Livestock are the Domestication, domesticated animals that are raised in an Agriculture, agricultural setting to provide labour and produce diversified products for consumption such as meat, Egg as food, eggs, milk, fur, leather, and wool. The t ...
, which were grazers as well. Though it could have climbed trees, it lacked adaptation for suspension or leaping.


References


Further reading

* * * * * * * * Catlett, Kierstin K, Laurie Godfrey and William Jungers. "Life History Space": A Multivariate Analysis of Life History Variation in Extant and Extinct Malagasy Lemurs. ''American Journal of Physical Anthropology'' 2010; * * * {{Taxonbar, from=Q632216 Subfossil lemurs Holocene extinctions Pleistocene first appearances