Lemur: Difference between revisions

| image_caption = A sample of lemur diversity; 8 of 150015 biological genera are depicted (from top, left to right): ''[[Ring-tailed lemur|Lemur]]'', ''[[Sifaka|Propithecus]]'', ''[[Aye-aye|Daubentonia]]'', {{extinct}}''[[Archaeoindris]]'', ''[[Mouse lemur|Microcebus]]'', ''[[Sportive lemur|Lepilemur]]'', ''[[True lemur|Eulemur]]'', ''[[Ruffed lemur|Varecia]]''.

'''Lemurs''' ({{IPAc-en|audio=En-us-Lemur.ogg|ˈ|l|iː|m|ər}} {{Respell|LEE|mər}}); (from Latin ''{{lang|la|lemures'' –}} {{lit|ghosts or |spirits}}) are [[Strepsirrhini|wet-nosed primates]] of the [[Superfamily (biology)|superfamily]] '''Lemuroidea''' ({{IPAc-en|l|ɛ|m|j|ʊ|ˈ|r|ɔɪ|d|i|ə}} {{respell|lem|yuurr|OY|dee|ə}}),<ref>{{Cite book|title=The Chambers Dictionary|publisher=Chambers|year=2003|isbn=0-550-10105-5|edition=9th|chapter=lemur}}</ref> divided into 8 [[Family (biology)|families]] and consisting of 15 [[genera]] and around 100 existing [[species]]. They are endemic to the island of [[Madagascar]]. Most existing lemurs are small, have a pointed snout, large eyes, and a long tail. They [[arboreal|chiefly live in trees]] and [[nocturnal|are active at night]].

Lemurs share resemblance with other [[primate]]s, but evolved independently from [[monkey]]s and [[ape]]s. Due to Madagascar's highly seasonal climate, [[Evolution of lemurs|lemur evolution]] has produced a level of [[species diversity]] rivaling that of any other primate group. Until shortly after humans arrived on the island around 2,000&nbsp;years ago, there were lemurs as large as a male [[gorilla]]. Most species have been discovered or promoted to full species status since the 1990s; however, lemur [[Taxonomy (biology)|taxonomic classification]] is controversial and depends on which [[Species problem|species concept]] is used.

LemursLiving lemurs range in weight from the {{convert|30|g|oz|adj=on}} [[mouse lemur]] to the {{convert|9|kg|lb|adj=on}} [[indri]]. Since the arrival of humans on the island around 2,000&nbsp;years ago, over a dozen species of "[[giant lemurs]]" larger than living lemur species have become extinct, including the gorilla-sized ''[[Archaeoindris]]''. Lemurs share many common basal primate traits, such as divergent [[digit (anatomy)|digits]] on their hands and feet, and [[nail (anatomy)|nails]] instead of [[claw]]s (in most species). However, their [[Brain-to-body mass ratio|brain-to-body size ratio]] is smaller than that of [[Anthropoidea|anthropoid]] primates. As with all [[strepsirrhine]] primates, they have a "wet nose" ([[rhinarium]]). Lemurs are generally the most social of the strepsirrhine primates, and communicate more with scents and vocalizations than with visual signals. Lemurs have a relatively low [[basal metabolic rate]], and as a result may exhibit [[dormancy]] such as [[hibernation]] or [[torpor]]. They also have [[seasonal breeder|seasonal breeding]] and [[dominance (ethology)|female social dominance]]. Most eat a wide variety of fruits and leaves, while some are specialists. Two species of lemurs may coexist in the same forest due to different diets.

Lemurs are primates belonging to the suborder [[Strepsirrhini]]. Like other strepsirrhine [[primate]]s, such as [[loris]]es, [[potto]]s, and [[galago]]s, they share ancestral (or [[Cladistics#plesiomorphy|plesiomorphic]]) traits with early primates. In this regard, lemurs are popularly confused with ancestral primates; however, lemurs did not give rise to monkeys and apes ([[simian]]s). Instead, they evolved independently in isolation on [[Madagascar]].{{R|1997Kay}} All inmodern strepsirrhines including lemurs are traditionally thought to have evolved from early primates known as [[adapiformes|adapiforms]] during the [[Eocene]] (56 to 34&nbsp;[[Year#Abbreviations yr and ya|mya]]) or [[Paleocene]] (66 to 56&nbsp;mya).{{Sfn|Sussman|2003|pp=149–229}}{{R|1997Kay}}{{Sfn|Gould|Sauther|2006|pp=vii–xiii}} Adapiforms, however, lack a specialized arrangement of teeth, known as a [[toothcomb]], which nearly all living strepsirrhines possess.{{Sfn|Ankel-Simons|2007|pp=392–514}}{{Sfn|Preston-Mafham|1991|pp=141–188}}{{Sfn|Tattersall|2006|pp=3–18}} A more recent [[hypothesis]] is that lemurs descended from lorisoids (loris-like) primates. This is supported by comparative studies of the [[cytochrome&nbsp;b]] gene and the presence of the strepsirrhine toothcomb in both groups.{{Sfn|Tattersall|2006|pp=3–18}}{{Sfn|Yoder|2003|pp=1242–1247}} Instead of being the direct ancestors of lemurs, the adapiforms may have given rise to both the lemurs and lorisoids, a split that would be supported by [[molecular phylogenetic]] studies.{{Sfn|Tattersall|2006|pp=3–18}} The later split between lemurs and lorises is thought to have occurred approximately 62 to 65&nbsp;mya according to molecular studies,{{R|2004YoderYang}} although other genetic tests and the fossil record in Africa suggest more conservative estimates of 50 to 55&nbsp;mya for this divergence.{{r|2006Godinot}} However, the oldest lemur fossils on Madagascar are actually [[subfossil]]s dating to the [[Late Pleistocene]].{{Sfn|Sussman|2003|pp=149–229}}

Once part of the supercontinent [[Gondwana]], the island of Madagascar has been isolated since it broke away from eastern [[Africa]] (~160&nbsp;mya), [[Antarctica]] (~80–130&nbsp;mya), and [[Indian Plate|India]] (~80–90&nbsp;mya).{{Sfn|Flynn|Wyss|2003|pp=34–40}}{{LoM2 Sfn|pp=23–26}} Since ancestral lemurs are thought to have originated in Africa around 62 to 65&nbsp;mya, they must have crossed the [[Mozambique Channel]], a deep channel between Africa and Madagascar with a minimum width of about 560&nbsp;km (350&nbsp;mi).{{Sfn|Tattersall|2006|pp=3–18}} In 1915, [[paleontologist]] [[William Diller Matthew]] noted that the mammalian biodiversity on Madagascar (including lemurs) can only be accounted for by random [[rafting event]]s, where very small populations rafted from nearby Africa on tangled mats of vegetation, which get flushed out to sea from major rivers.{{R|1915Matthew}} This form of [[biological dispersal]] can occur randomly over millions of years.{{Sfn|Tattersall|2006|pp=3–18}}{{Sfn|Garbutt|2007|pp=14–15}} In the 1940s, American paleontologist [[George Gaylord Simpson]] coined the term "sweepstakes hypothesis" for such random events.{{R|NatureNews_20Jan10}} Rafting has since been the most accepted explanation for the lemur colonization of Madagascar,{{R|2008Horvath}}{{Sfn|Krause|2003|pp=40–47}} but until recently, this trip was thought to be very unlikely because strong [[ocean current]]s flow away from the island.{{R|2010AliHuber}} In {{Nowrap|January 2010}}, a report demonstrated that around 60&nbsp;mya both Madagascar and Africa were 1,650&nbsp;km (1,030&nbsp;mi) south of their present-day positions, placing them in a different [[ocean gyre]], producing currents that ran counter to what they are today. The ocean currents were shown to be even stronger than today, which would have pushed a raft along faster, shortening the trip to 30&nbsp;days or less—short enough for a small mammal to survive easily. As the [[plate tectonics|continental plates]] drifted northward, the currents gradually changed, and by 20&nbsp;mya the window for oceanic dispersal had closed, effectively isolating the lemurs and the rest of the terrestrial Malagasy fauna from mainland Africa.{{R|2010AliHuber}} Isolated on Madagascar with only a limited number of mammalian competitors, the lemurs did not have to compete with other evolving [[arboreal locomotion|arboreal]] mammalian groups, such as [[squirrel]]s.{{Sfn|Sussman|2003|pp=107–148}} They were also spared from having to compete with [[monkey]]s, which evolved later. The intelligence, aggression, and deceptiveness of monkeys gave them an advantage over other primates in exploiting the environment.{{Sfn|Garbutt|2007|pp=85–86}}{{Sfn|Preston-Mafham|1991|pp=I'm ehh I'm 141–188}}

Before the arrival of humans roughly 1500 to 2000&nbsp;years ago, lemurs were found all across the island.{{Sfn|Sussman|2003|pp=107–148}} However, early settlers quickly converted the forests to [[paddy field|rice paddies]] and [[grassland]] through [[slash and burn|slash-and-burn]] agriculture]] (known locally as ''tavy''), restricting lemurs to approximately 10% of the island's area, ~60,000&nbsp;km² (23,000&nbsp;sq mi).{{Sfn|Preston-Mafham|1991|pp=10–21}} Today, the diversity and complexity of lemur communities increases with [[flora]]l diversity and [[precipitation (meteorology)|precipitation]] and is highest in the [[rainforest]]s of the east coast.{{Sfn|Sussman|2003|pp=149–229}} Despite their adaptations for weathering extreme adversity, habitat destruction and hunting have resulted in lemur populations declining sharply, and their diversity has diminished, with the recent extinction of at least 17&nbsp;species in eight genera,{{Sfn|Sussman|2003|pp=107–148}}{{LoM2 Sfn|pp=37–51}}{{R|2009Gommery}} known collectively as the [[subfossil lemur]]s. Most of the approximately 100&nbsp;species and subspecies of lemur are either threatened or endangered. Unless trends change, extinctions are likely to continue.{{Sfn|Burney|2003|pp=47–51}}

|1={{Clade[[Lemuridae]]

{{Main list|List of lemur specieslemuroids}}

| [[Indriidae]], {{extinct}}[[Palaeopropithecidae]] || align=center|{{DentalFormula|upper=2.1.2|lower=2.1.3|total=22}}{{efn|No infant ''[[Mesopropithecus]]'', ''[[Babakotia]]'', or ''[[Archaeoindris]]'' remains have been found, and little is known about the deciduous dentition of ''[[Palaeopropithecus]]''. Developmental patterns are inferred from the developmental patterns of their closest relatives, the indriids.{{Sfn|Godfrey|Petto|Sutherland|2001|pp=113–157}}}} || align=center|{{DentalFormula|upper=2.1.2.3|lower=2.0.2.3|total=30}}{{efn|In indriids, either a pair of deciduous lower incisorincisors or lower caninecanines isare not replaced in permanent dentition. Differing interpretations of this yield different dental formulae. Therefore an alternative dental formula for this family is {{DentalFormula|upper=2.1.2.3|lower=1.1.2.3|total=30}}.{{Sfn|Ankel-Simons|2007|pp=224–283}}}}

The toothcomb in lemurs normally consists of six teeth (four incisors and two canines), although indriids, monkey lemurs, and some sloth lemurs only have a four-tooth toothcomb due to the loss of either a caninepair orof ancanines or incisorincisors.{{Sfn|Tattersall|2006|pp=3–18}}{{Sfn|Cuozzo|Yamashita|2006|pp=67–96}} Because the lower canine is either included in the toothcomb or lost, the lower dentition can be difficult to read, especially since the first premolar (P2) is often shaped like a canine (caniniform) to fill the canine's role.{{Sfn|Ankel-Simons|2007|pp=224–283}} In [[folivore|folivorous]] (leaf-eating) lemurs, except for indriids, the upper incisors are greatly reduced or absent.{{Sfn|Ankel-Simons|2007|pp=224–283}}{{Sfn|Cuozzo|Yamashita|2006|pp=67–96}} Used together with the toothcomb on the [[mandible]] (lower jaw), this complex is reminiscent of an [[ungulate]] [[Dental pad|browsing pad]].{{Sfn|Cuozzo|Yamashita|2006|pp=67–96}}

Olfaction is particularly important to lemurs,{{Sfn|Sussman|2003|pp=149–229}} except for the indri, which lacks most common lemur scent glands and has a greatly reduced olfactory region in the brain.{{Sfn|Powzyk|Mowry|2006|pp=353–368}} Olfaction can communicate information about age, sex, reproductive status, as well as demarcate the boundaries of a territory. It is most useful for communication between animals that rarely encounter each other.{{Sfn|Sterling|McCreless|2006|pp=159–184}} Small, nocturnal lemurs mark their territories with [[urine]], while the larger, diurnal species use scent glands located on various parts of their anatomy. The ring-tailed lemur engages in "stink fights" by rubbing its tail across scent glands on its wrists, and then flicking its tailit at other male opponents. Some lemurs [[defecation|defecate]] in specific areas, otherwise known as [[latrine behavior]]. Although many animals exhibit this behavior, it is a rare trait among primates. Latrine behavior can represent territorial marking and aid in interspecies signaling.{{Sfn|Ankel-Simons|2007|pp=392–514}}

[[File:Avahi lanigermeridionalis 002.jpg|thumb|right|upright|alt=A baby woolly lemur clings to its mother's back as she clings to a tree.|[[Woolly lemur]]s are nocturnal and typically give birth to one offspring, which they carry with them while foraging.]]

[[Scent]] factors heavily into lemur reproduction. Scent-marking activity escalates during the [[Estrous cycle|mating season]]. Pheromones may coordinate reproductive timing for females coming into estrus.{{Sfn|Ankel-Simons|2007|pp=521–532}} [[Mating]] can be either [[monogamy in animals|monogamous]] or [[promiscuityPromiscuity#Other animals|promiscuous]] for both males and females, and mating can include individuals from outside the group.{{Sfn|Sussman|2003|pp=149–229}}{{Sfn|Sussman|2003|pp=257–269}} Monogamous lemurs include the [[red-bellied lemur]] (''Eulemur rubriventer'') and the [[mongoose lemur]] (''E. mongoz''), although the mongoose lemur has been observed mating outside of its pair bond.{{Sfn|Sussman|2003|pp=257–269}} Monogamy is most common among nocturnal species, although some exhibit scramble competition, sexual suppression of subordinates, or competitions between males that avoid direct fighting.{{Sfn|Godfrey|Jungers|Schwartz|2006|pp=41–64}} In mouse lemurs, males utilize [[Mating plug|sperm plugs]], developed enlarged [[Testicle|testes]] during the mating season, and develop size dimorphism (likely due to the enlarged testes). These indicate a mating system known as scramble competition polygyny, where males cannot defend females or the resources that might attract them.{{Sfn|Kappeler|Rasoloarison|2003|pp=1310–1315}}

Lemurs have also become popular in [[Western culture]] in recent years. The [[DreamWorks Animation]] franchise ''[[Madagascar (franchise)|Madagascar]]'' features the characters [[King Julien]], [[List of Madagascar characters#Maurice|Maurice]] and [[Mort (Madagascar)|Mort]] and was seen by an estimated 100&nbsp;million people in theaters and 200–300&nbsp;million people on DVD worldwide.{{LoM2 Sfn|pp=85–88}} Prior to this film, ''[[Zoboomafoo]]'', a [[Public Broadcasting Service]] (PBS) children's television series from 1999 to 2001,{{R|WashingtonTimes1021}} helped to popularize sifakas by featuring a live [[Coquerel's sifaka]] from the Duke Lemur Center as well as a puppet.{{R|USAToday0330}} The [[Disney Channel]] series, ''[[Bear in the Big Blue House]]'' one of the characters, Treelo, is a lemur. A twenty-episode series called ''Lemur Kingdom'' (in the United States) or ''[[Lemur Street]]'' (in the United Kingdom and Canada) aired in 2008 on [[Animal Planet]]. It combined the typical animal [[documentary film|documentary]] with [[dramatic programming|dramatic narration]] to tell the story of two groups of ring-tailed lemurs at Berenty Private Reserve.{{R|NYDailyNews0208|WashingtonPost0208|AfricaNews1228|TGAM0208}}

<ref name="2009Groeneveld">{{Cite journal | last1 = Groeneveld | first1 = L. F. | last2 = Weisrock | first2 = D. W. | last3 = Rasoloarison | first3 = R. M. | last4 = Yoder | first4 = A. D. | last5 = Kappeler | first5 = P. M. | title = Species delimitation in lemurs: multiple genetic loci reveal low levels of species diversity in the genus ''Cheirogaleus'' | doi = 10.1186/1471-2148-9-30 | journal = BMC Evolutionary Biology | volume = 9 | pages = 30 | year = 2009 | issue = 1 | url= | pmid = 19193227| pmc = 2652444 | doi-access = free | bibcode = 2009BMCEE...9...30G }}</ref>

<ref name="2008Braune">{{Cite journal | last1 = Braune | first1 = P. | last2 = Schmidt | first2 = S. | last3 = Zimmermann | first3 = E. | title = Acoustic divergence in the communication of cryptic species of nocturnal primates (''Microcebus ssp.'') | doi = 10.1186/1741-7007-6-19 | journal = BMC Biology | volume = 6 | issue = 19 | pages = 19 | year = 2008 | pmid = 18462484| pmc =2390514 | doi-access = free }}

<ref name="2008Orlando">{{Cite journal | last1 = Orlando | first1 = L. | last2 = Calvignac | first2 = S. | last3 = Schnebelen | first3 = C. | last4 = Douady | first4 = C. J. | last5 = Godfrey | first5 = L. R. | last6 = Hänni | first6 = C. | doi = 10.1186/1471-2148-8-121 | title = DNA from extinct giant lemurs links archaeolemurids to extant indriids | journal = BMC Evolutionary Biology | volume = 8 | issue = 121 | pages = 121 | year = 2008 | url= | pmid = 18442367| pmc = 2386821 | doi-access = free | bibcode = 2008BMCEE...8..121O }}</ref>

<ref name="2007Tattersall">{{Cite journal | last1 = Tattersall | first1 = I. | author-link1 = Ian Tattersall | doi = 10.1002/evan.20126 | title = Madagascar's Lemurs: Cryptic diversity or taxonomic inflation? | journal = [[Evolutionary Anthropology (journal)|Evolutionary Anthropology: Issues, News, and Reviews]] | volume = 16 | issue = 1| pages = 12–23 | year = 2007 | s2cid = 54727842 | doi-access = free }}</ref>

<ref name="2004YoderYang">{{Cite journal | last1 = Yoder | first1 = A. D. | last2 = Yang | first2 = Z. | doi = 10.1046/j.1365-294X.2004.02106.x | title = Divergence dates for Malagasy lemurs estimated from multiple gene loci: geological and evolutionary context | journal = Molecular Ecology | volume = 13 | issue = 4 | pages = 757–773 | year = 2004 | url = http://www.biology.duke.edu/yoderlab/reprints/2004Yoder%26Yang_jme.pdf | pmid = 15012754 | bibcode = 2004MolEc..13..757Y | s2cid = 14963272 | access-date = 2015-09-04 | archive-date = 2013-08-23 | archive-url = https://web.archive.org/web/20130823224517/http://biology.duke.edu/yoderlab/reprints/2004Yoder%26Yang_jme.pdf | url-status = live }}</ref>

<ref name="1976Ehrlich_et_al">{{Cite journal | last1 = Ehrlich | first1 = A. | last2 = Fobes | first2 = J. | last3 = King | first3 = J. | doi = 10.1016/0047-2484(76)90005-1 | title = Prosimian learning capacities | journal = Journal of Human Evolution | volume = 5 | issue = 6 | pages = 599–617 | year = 1976 | bibcode = 1976JHumE...5..599E }}</ref>

<ref name="IBT_21Aug13">{{cite news|last1=Mintz |first1=Z. |title=Lemurs face extinction in 20 years, risk of losing species rorfor 'first time in two centuries' |url=http://www.ibtimes.com/lemurs-face-extinction-20-years-risk-losing-species-first-time-two-centuries-1393907 |newspaper=International Business Times |date=21 August 2013 |archive-url=https://web.archive.org/web/20130826134422/http://www.ibtimes.com/lemurs-face-extinction-20-years-risk-losing-species-first-time-two-centuries-1393907 |archive-date=26 August 2013 |url-status=live |access-date=24 August 2013}}</ref>

<ref name="LCF_Myakka">{{cite web | title = Myakka City Lemur Reserve | url = http://www.lemurreserve.org/myakka.html | work = Lemur Conservation Foundation | publisher = Lemur Conservation Foundation | access-date = 18 April 2013 | archive-date = 4 May 2013 | archive-url = https://web.archive.org/web/20130504075520/http://www.lemurreserve.org/myakka.html | url-status = live }}</ref>

:*{{cite book|last = Cartmill|first = M.|url = https://books.google.com/books?id=hv28p1tCnnEC&pg=PA10|pages = 10–30|year = 2010|title = Primate neuroethology - Chapter 2: Primate Classification and Diversity| publisher=Oxford University Press |isbn = 9780199716845|access-date = 2020-07-04|archive-date = 2023-04-13|archive-url = https://web.archive.org/web/20230413121959/https://books.google.com/books?id=hv28p1tCnnEC&pg=PA10|url-status = live}}