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Home , Archaeolemur, Indriidae, Mesopropithecus, Sifaka

THE :A LIFE HISTORY by Mary Deborah Robinson

Dr. Steve Herman Vertebrate Biology The Evergreen State College Olympia, Washington

Fall Quarter, 1980 The Indriidae (Burnett, 1828) by Mary Deborah Robinson :- •- Avahi (Jourdan, 1834) Propithecus (Bennett, 1832) Tndri (E. Geoffroy and Cuvier, 1795) CONTEXT AND CONTENT. Order . Suborder Prosimii. Infraorder . Superfamily Lemuroidea. Indriidae. This classification follows Simpson, 1945. Also in use is a taxonomic order suggested by Hill, 1953, which introduces a Grade, Strepsirhini, before the proposed Suborder, Lemuroidea. Another scheme was proposed by Romer, 1967, which makes Lemuroidea a Suborder, but lumps the Indriidae with the Family Daubentoniidae, of which there is one extant , the Aye-Aye. Tattersall suggests that there are three subfamilies: Indriinae, with living representatives, and the extinct Archaeolemurinae and Palaeopropithecinae. Szalay describes a slightly different group of the extinct forms; both ideas will be reviewed later. This paper deals primarily with the extant forms. There are three living genera, four species and twelve subspecies. Avahi laniger (Gmelin, 1788) type species. Propithecus diadema (Bennett, 1832) type species. Propithecus verreauxi (A. Grandidier, 1867) type species. indri (Gmelin, 1788) type species. CONTEXT AND CONTENT. As described above, however there are two generally agreed upon subspecies of Avahi and ten described species of Propitheci. Avahi laniger laniger (Gmelin, 1788) Dark reddish color, lives in most humid eastern forest of and is particularly common in the coastal region. A. 1. occidentalis (Lorenz, 1898) Light reddish grey coloring with white thighs living in forests of western Madagascar and in the southwest. Propithecus diadema (Bennett, 1832) Head to base of tail about 50 cm. Vocalization is a series of cries from growls to hoarse barks uttered in unison. Name in Malagasy is "chim-poun" which appears to be an imitation of the growl. Males have a gland near the skin surface visible at the join between the chest and neck. It is used for marking territory. The have a thick coat. There are several forms scattered from North to South along the eastern coast of Madagascar. According to Petter, they are as follows: P_._ d. perrieri (Lavauden, 1931) Black coat, Far North. P_._ d_._ candidus (Grandidier, 1871) White coat, head lightly tinged with grey, lives in Sambava-Andapa region. P. d_._ diadema (Bennett, 1832) Grey coat, black head, limbs tinged with yellow, lives between Mananara and Tamatave. P_._ d. edwardsi (A. Grandidier, 1871) Chocolate brown coat on limbs, head, upper part of back and tail, color turns to beige on front of body. Lives in central part of eastern forest. P_. d. holomelas (Gunther, 1875) Black coat turning to brownish on front with lighter colored triangle at the base of the spine. Idanadiana region. .

The Indriidae -2- 1 M. Robinson X'*B.,-

Propithecus verreauxi (A. Grandidier, 1867) This is smaller than P. d., also thinner with a sparser coat and distributed throughout western Madagascar. The Malagasy name for tine species is "chi-fac" imitating the wheezing noise the makes when disturbed. The common name for all Propitheci is after this vocalization. These animals are very trusting, extremely affectionate, and have no defenses. They are rapidly disappearing. The subspecies, according to Fetter, are listed below. p. y_._ cocfuereli (A. Milne Edwards, 1867) White coat, bright reddish brown spots on upper part of thighs and arms, brownish stomach, black face, golden eyes. Ankarafantsika region of Madagascar. P. v. deckeni (Peters, 1870) White all over. Antsalova-Soalala region. P. v. coronatus (A. MilntuEdwads, 1871) White coat tinged with pale grey on back, red on chest, black head. Between Majunga and Soalala P_._ v. verreauxi (Grandidier, 1876) White all over, top of head dark brown with white band on forehead. Found between south and southwestern region of Madagascar. P. v. majori (Rothchild, 1894) Similar to P. v. v., but much black coloring on upper part of arms, thighs and back. Southwest, particularly in Sakaraha region. Possibly extinct. DIAGNOSIS. The following characters are diagnostic of both and species: extended hallux; short; pelage long, although face inevitably black and sparsely haired; dental formula is 2.1.2.3 with a tooth comb composed of one pair of 2.0.2.3 and the canines; indriids have large hypocones on the upper molars. The face and are usually foreshortened, and mandibular angle is expanded. Hands are finely elongated; on their feet they have a toilet claw. Cutaneous glands run vertically along the throat. Their diet is folivorous and frugivorous. Powerful hindlimbs propel their vertical climbing and leaping locomotion. These arboreal are the largest living prosimians. They are bipedal on the ground. Primarily diurnal, their distinctive vocalizations are heard only on the island of Madagascar. Gregarious, the animals are found usually in family groups.

GENERAL CHARACTERISTICS. With the exception of the Avahi, these large lemurs are diurnal, leaping from tree trunk to tree trunk. Recorded bounds are between 30 and 40 feet. Characteristically the animal takes off on long leaps in a head first dive with the arms over the head and reverses itself in mid-leap, landing feet first, followed by hands, in a vertical position. For small leaps the animals push off and land holding the body vertical throughout. On the ground the lemurs run and leap bipedally with the arms carried over the head. Indriidae possess long silky dense fur with distinctive patterns by which it is believed individuals are identified. The lemurs appear to be equally dependent upon vision, olfactory sense, and hearing. Indriidae feed primarily upon leaves, supplemented by fruit, flowers and bark. They are vocal and territorial, living in groups of between 2-6 individuals which always contain an adult of either sex and young. The Indriidae — 3 — M. Robinson

GENERAL CHARACTERISTICS (Cont'd). The Indriidae breed seasonally, bearing their young between July and September after a relatively long gestation period of five months. Infants are born with eyes open, a thin covering of hair, and the ability to grasp their mother's fur. They hang horizontally across their mother's stomach, below the pair of pectoral mammaries. After one month the infant will move to the mother's back and remain there until six months old. Infants are very attractive to adult Indriidae who spend much time grooming them. Indriidae are mature at approximately two and one half years. Adults spend most of their time eating and resting in the forks of trees. These animals communicate with extensive vocalizations and complicated behaviors which include grooming and playing. Indri indri is the largest family member with a head and body length of 700 mm and a stubby tail approximately 30mm. Standing bipedally with its arms over the head, its proportions ressemble a human. It has a longer, blunter snout than Propitheci, a rounded head shape, and small but obvious rounded ears. Occupying crests in the medium altitude areas of the eastern forests, at the slightest alarm it departs for the valleys with spectacular leaps like an arboreal kangaroo. Its cries include loud warning barks and varied growls. When calm a family on a hill will take up long modulated calls with individual family members singing in harmony. These calls carry long distances, and when one group is finished, a neighboring groups will begin. Indri are believed to be monogamous, and female dominant, reproducing once every three years. The animals have 40 chromosomes (Rumpler and Albignac, 1973c). The long hindlimb bears a very divergent toe. There is no dimorphism in size or color which varies as follows (Burton, 1969). The general color is black and white. The head, neck, shoulders, back, arms, and hands are black. The rump extending up the back is white, washed with reddish flanks. The insides of the thighs are grey, but the outside of the hindlimbs is black, as is .the face. Variations include (a) the top of the head all white with throat and legs grey, and flanks and heels being bright red; (b) a patch of grey over each eye, and grey , shanks and undersides; (c) pure white albinos with pink eyes. Normally the eyes are large, yellow-brown in color with circular pupils (Napier, 1973). Related to the large Indri is the Avahi laniger or WooljLy Indri. This is the smallest of the indriidae with a soft, thick woolly fur which has an overall grey appearance although the individual hairs change from grey at the base to brown to black at the tip (Napier, 1973) There is a white band on the forehead, and the underparts are grey or white with a rufous tinge. The tail, hands and feet are rust colored The Avahi has a rounded, naked face with a short muzzle. The ears are small and hidden. The eyes are very large with a pupil forming a vertical slit. The animal is nocturnal and spends the day curled up in dense undergrowth either in the fork of a tree or clinging to a branch. It has long slender hands and feet. In both extremeties, .: • (Z.96T '

-, The Indriidae -4- M. Robinson

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GENERAL CHARACTERISTICS (cont'd)the 3rd, 4th and 5th digits are webbed. The big toe is widely divergent. Like the other indriidae, the second toe is modified into a "toilet claw." The head and body length is between 300 - 330 mm and the tail length is longer than the body length, between 390-395 mm. Avahi possesses 64 chromosomes. It is strictly an arboreal vegetarian, occurring singly or in pairs and found primarily near the southeastern coast. Propithecus, the Sifaka or monkey lemur, is medium sized. Its head and body length are between 458 - 534mm and the tail length ranges between 485-560 mm (Napier, 1973). The fur is very silky, and has been described in detail with the subspecies. The face is round, short with a naked black muzzle. The large eyes are forwardly directed, providing a staring quality; the iris is golden. Often the crown of the head is black or brown, separated from the face by a white band. is modified, as in all lemurs, to form a "dental comb" with which the animal scrapes off bark as well as grooms others. for the most part have 48 chromosomes; P. d. diadema and P. d. perrier have only 42 (Rumpler and Albignac, I973c) Propithecus is the most ubiquitous of the Indriidae and found through- out Madagascar from the coast to jungle at the edge of the great central plateau. Unfortunately that has not saved this most beautiful of lemurs from the near which all the Indriidae face. However, it has been studied more than the others, and the observations pertaining to behavior will be detailed in that section. Like the other Indriidae it is an arboreal vegetarian which moves through the trees by vertical clinging and leaping. Sifakas are generally found in larger groups which may be foraging units rather than strict family groups. They are diurnal and somewhat more aggressive when defending their territory than the other Indriidae. DISTRIBUTION. The Indriidae are found only on the island of Madagascar. Madagascar is the fourth largest island in the world, 995 miles long and 230,000 square miles. It lies in the S. Indian Ocean between 11° 57' and 25° 32' s. latitude, almost entirely within the tropical zone. The Mozambique Channel currently separates Madagascar from the eastern coast of Africa by between 220 miles and 750 miles. The topography is assymmetrical; there is a narrow coastal plain on the eastern side, a relatively high central plateau, and plains to the west. The two seasons follow each other with a month of transition. In general Winter (May - October) is coller and drier while Summer (November - April) is hot and wet. The west coast is warmer than the eastern coast by a few degrees. Average temperatures are 77°F in the North and 72°F in the Couth for the coasts. The interior is cooler by about 3°F/1000 feet. Maximum rainfall is 200 inches and minimum is 4.7 inches. Indri indri lives in the eastern rain forest between 14° - 20° south latitude. Its range extends from sea level to 5900 feet (Napier, 1973). Only the aye-aye has as restricted a distribution as the Indri which inhabits one of the most southern and elevated rain forests of the world. Indri and sympatric lemurs (including Propithecus verreauxi verreauxi (Napier, 1967)

. r Propithecus verreauxi verreauxi (Jolly, 1980) Propithecus verreauxi ccquereli (Jolly, 1980)

: •;* : BBS

M The Indriidae -5- M. Robinson

DISTRIBUTION (Cont'd) some Propitheci) endure very low temperatures for a tropical . During the winter, temperatures of 0 F have been recorded(Polluck, 1975). Population density varies considerably throughout the small area. Between the dense humid coastal jungles and the rugged volcanic terrain within the territory it has been virtually impossible for field researchers to accurately estimate numbers. Until recently both subspecies of Avahi laniger were fairly common. They are eaten by the locals which could be sustained by the species were it not for the awesome destruction of the forest habitat. This is at the heart of the extinction problem for all Madagascar wildlife. The eastern subspecies, A_._ 1. laniger, formerly inhabited the forested regions of the northeastern, eastern and southcentral areas from the coast to the foothills of the central plateau. A. 1. occidentalis is found along the northwestern coast from the Sambirano forest region south to the Bay of Bombetoka (Cox,1975). That same northwestern region is the only area, besides the central plateau, were there are no Propitheci. In general, PJL. verreauxi is found in the drier forests of the west as well as the dry southwestern Euphorbia forest. P. diadema lives in the rain forests of the eastern coast where it is sometimes sympatric with both Indri indri and Avahi laniger. FOSSIL RECORD During the Eocene, lemurs were cosmopolitan. They existed in Europe and North America where they comprised most of the fossil group, Northarctidae. By the end of the Eocene, they had disappeared from both North America and Europe. Now they exist only on Madagascar, with close relatives in the Asian tropics and Africa. It is widely held that an ancestral lemur species succeeded in colonizing Madagascar in the early Tertiary (Martin, 1971). During this period The Mozambique Channel was increasing in width but was not broad enough to prohibit colonization by "rafting," as suggested by Millot (1952). It is postulated that ridges on the continental shelf ma-y have been exposed and served as way stations. The rafts themselves were probably uprooted trees and other forest debris onto which an arboreally specialized animal might cling to successfully. Subsequently, the Mozambique Channel widened as part of the general continental drift and a rising sea level prohibiting further emigration. This isolation permitted adaptive radiation to occur on Madagascar in virtually a closed system. This theory serves to explain why 95% of Madagascar's flora and fauna are endemic yet exhibiting affinities with primarily African species (Martin, 1971). Unfortunately no fossils have yet been found which connect the extant Malagasy lemurs with the ancestral prosimian (Fetter, 1972). However, there have been found on Madagascar a number of subfossil lemurs representing species which have only recently become extinct, certainly within the coming of Homo which was probably the cause of their demise judging from skeletal evidence. most closely ressembles the living Indriidae. Suhfossil lemur (Tananarive Zoo).

' The Indriidae -6- M. Robinson

•FOSSIL RECORD (Cont'd) There are two known species excavated at five different sites (Szalay, 1979): 1. Mesopropithecus pithecoides Standing, 1905, type species. 2. M. qlobiceps (Lamberton, 1936b) The are within the Indri size range although the cranial proportions are more like Propithecus. The indriid dentition pattern is present. In general the subfossil is more robust, and the skeleton is less like the living indriidae than the . It is inferred that the animal was herbivorous (folivorous) and possibly quadrupedal (Tattersall, 1971). Archaeolemuridae differ from living indriidae by retaining the original three of an indroid ancestor. The tooth t^^ comb has been modified to form cutting teeth which function with enlarged incisors. Also the cheek teeth are compressed. The skeleton shows adaptation for semiterrestrial life. There are two genera and three species. has comparison points with the gelada but not enough skeletal evidence is available to determine whether or not it was a terrestrial runner. Tattersall has compared to a monkey and Hadropithecus to an . The species are as follows (Szalay, 1979): 1. Archaeo1emur majori Filhol, 1895, type species. 2. A. edwardsi (Filhol, 1895). 3. Hadropithecus stenoqnathus Lorenz, 1899, type species. It is possible that Hadropithecus is responsible for a legend of the Bara people in southwestern Madagascar which describes the Kalanoro, little men with long hair who were lithe runners and climbers who came out of the forests to steal food from the local villages (Tattersall, 1972). There are some very large remains, grouped in the Family Palaeopropithecidae. Generally this group is primitive when compared with the Indriidae in all features yet the basic structure shows a relationship to the Indriidae as well as Meqaladapis, an independently evolving form. The ear is extremely primitive, and the extremities long enough to brachiate, although it probably hung like an orangutan (Tattersall, 1972). The species are (Szalay, 1979): 1. G. Grandidier, 1899, type species. 2. Archaeoindris fontoynonti Standing, 1908, type species. Radiocarbon dating of the twelve subfossils now identified shows deposit dates between 2,850 and 980 B.P. Direct evidence of their demise in the hands of man comes as axe marks on bones, burned bones and pottery shards with their bones (Tattersall, 1972). Sieur Etienne de Flacourt was the first European to describe the Malagasy lemurs. Among his notations written in 1658 was the following: The Indriidae -7- M. Robinson

FOSSIL RECORD (Cont'd) * "Tretretretre, or tratratratra, an animal as big as a two year old calf, with a round head and the face of a man. It has wooly hair, a short tail, and eyes like those of a man...It can be seen near the Lipomani Lake, in the region of which is its lair. It is a solitary animal? the local people fear it greatly, and flee from it as it does from them." Tattersall. "Of Lemurs and Men," Natural History (3)72, p38. Flacourt was known for his accuracy yet this reference has not been identified among the known Malagasy fauna. Was it the subfossil, Meqaladapis, as Tattersall suggests? The subfossils became extinct very recently. It is possible that the living Indriidae evolved to inherit the niches vacated by the subfossils. Martin the development of a "membraneous tapetum lucidum" located behind the retina which classifies lemurs as Strepsirhines and is generally regarded as an adaptation for nocturnal habits. Similar features are found in other nocturnal , yet an analogous structure is absent in clearly diurnal monkeys and . The presence of the membrane in Indri and Propitheci suggests these species may have evolved diurnal behavior relatively recently (Martin, 1971) . Since there are no large predators on Madagascar except man, the main evolutionary factor may be competition for food sources. The geography and environment is finite hence it seems reasonable to assume that if niches become available there will be impetus to fill them. Lemurs competing for the same food sources now are adapted to nocturnal, crepuscular, and diurnal activity. Therefore, it seems reasonable to accept that the extinction of the large Indriidae ancestors had an evolutionary impact upon those members of the family still living. FORM. Morphologically, the Indriidae form a fairly homogeneous family although they differ in body weight from 1.3 kg in Avahi to 3.5 kg in Propithecus to 5.3 kg in Indri (Gingerich and Ryan, 1977). Dental measurements, although varied throughout the family, indicate that there is no sexual dimorphism present, and the variation is well within the mammalian variables (Gingerich and Ryan, 1977). The indriidae have a eruption sequence which is posterior to anterior, P4-P3-P2, as opposed to the general prosimian pattern, P2-P4-P3 (Schwartz, 1975). Their tooth scraper, which all lemurs have, is formed by a single pair of lower incisors and canines. The Indriidae -8- M. Pobinson

FORM. The surfaces of the teeth and their relationship to one another are indicative of the animals' feeding habits. There is very little variation in cranial measurements; cranial length ranges from a low of 3.3 in Indri to a high of 4.6 in Propithecus verreauxi. Likewise, width ranges from 4.1 in the Indrj. to 6.5 in P. verreauxi. Orbital diameter much larger in the nocturnal Avahi than either of the two diurnal animals despite their larger size. Avahi and Propitheci male skulls appear to be slightly larger than female skulls; the reverse is true of Indri (Gingerich and Ryan, 1977). Again no sexual dimorphism^apparent in the skull of Indriidae. Propitheci possess a more rounded and shorter facial region than the others. In Indri the facial region is prognathous and the auditory bullae extremely prominent (Napier, 1967). Also Napier cites a larger post glenoid tubercle for whose mandible is longer and narrower than that of Propithecus. Propithecus, like Avahi, has an oblique symphysis generally associated with procumbent teeth (Napier, 1967). The angular region, Napier notes, is rounded and expanded compared with Indri. In Propithecus the foramen magnum is directed both down and backwards; the foramen magnum of Indri is very large, slightly larger in the male than in the female (Gingerich and Ryan, 1977). Scapula A clavicle is always present in primates. In Propithecus, the border is straight and the wide enough to accommodate large rotator cuff muscles which secure the shoulder joint (Roberts and Davidson, 1975). Propithecus diadema has a broader blade index than Propithecus verreauxi, but the process! and other features are very similar. Indri indri possesses a long and broad scapula sized between Propithecus spp. and other Lemurs. Avahi ressembles Indri but is smaller(Roberts and Davidson, 1975). Hindiimb The hindlimbs of the Indriidae are much longer than the forelimbs by as much as 130%-155%. Compared with trunk length, hindlimbs of lemurs in general shortest in Primate order. Among the Indriidae, when the femur is longest, the foot is the shortest. The Indri is closer to human proportioning (femur to foot, or the crural index) than Pan or Gorilla. The indriidae have thick squat ; the illium is short and blade-like, triangular in shape. The femur is very straight, the shaft is subcircular. One unique prosimian feature is the third trocanter represents the terminal tubercle-of the crest ct" the insertion of the gluteus maximus (Jouffroy, 1975). The patella is half cartilagenous, half bony sesamoid. The hindlimb muscles are innervated by branches of the lumbosacral plexus (Jouffroy, 1975). Hip and thigh muscles controlled by collateral branches of the sacral plexus as well as femoral and obturator nerves; the lower leg and feet are signaled by the nn. ischiadicus doralis and ischiadicus ventralis (Jouffroy, 1975). The numerous is considered robust. Crests and grooves supporting the musculature are extensive and typically primate. The pectoral girdle is innervated by an accessory nerve and cervicle vertebral branches (Jourfroy, 1975). Brachial plexus The Indriidae -9- M. Robinson

is the nerve center for the limb muscles. Indriidae have extensive extensor muscles as well as well developed brachioradials (Jouffroy, 1975). Foot Indriidae possess semi-digitigrade feet which are more specialized than their hands. The large wide hallux is opposed to the other toes. The tarsus is raised during locomotion and the weighc borne by both tarsometatarsal and last interphalangeal joints (Jouffroy, 1975). Papillary crests on the sole are considered an evolved feature. In Indri, the entire sole is covered with minute crestsj in Avahi and Propitheci, a small central section is lacking the crests (Jouffroy, 1975). Each toe has a nail except for the second which bears the characteristic lemur toilet claw. An interdigital web extends between digits III, IV, and V. Metatarsals very long which is much like a monkey in proportioning. The muscular of the foot is typically primate except Propithecus has an extremely strong adductor hallucis (Jouffroy, 1975). Hand The most striking difference between the Indriidae hand and the Anthropoid hand is that the axis of the hand passes through the 4th digit rather than the third. The tactile pads are arranged in three sets and covered with papillary crests, parallel or in loops (Jouffroy, 1975). The interdigital web extends between the 3rd, 4th and 5th digits. Indri have extremely elongated fingers, the length being six times the width. The digital formula is IV III V II. Musculature and bone formation is consistent with higher primates, notably the (Jouffroy, 1975). The thumb is highly divergent from the other metacarpals. Ear Beginning with subfossil Indriines, the exteriorization of the tympanic wall and formation of exterior auditory meatus demonstrates some of the remarkable parallel evolution which occurred in other primates (Saban, 1975). Indri possess better developed auricles than other Indriidae (Petter and Peyrieras, 1974). Alimentary System The salivary glands are very large in all Indriidae. In Avahi laniqer the viscera are bulky and capacious. The stomach has incipient sacculation, and the gall bladder is absent Napier, 1967) Propithecus has extremely strong chewing muscles and a large, complex stomach without sacculations. The intestines are 10 to 15 times the body length. There is a very definite gall bladder. The colon is coiled in loops, sited in the R. hypochondrium (Napier, 1967) Special^ features All indriidae have small, oval, paired cutaneous glands in the front of their necks below the jaw angle. Males have cutaneous glands in the scrotal area. The Indri has a large laryngeal sac posterior to the trachea and opening into it below the cricoid (Napier, 1967). The Indriidae -10- M. Robinson FUNCTION Roberts and Davidson have observed the following related to functional systems. Vertebrate muscular skeletal systems transfer loads to maximize efficiency of movements which are essential to the behavior of the animal. Hence the correlation is obvious between morphology and behavior. In their studies (Roberts and Davidson, 1975), they note that the narrowness of the scapula blade and the broad fossae enhance rapid forelimb movement. The scapula design of all Indriidae is characteristic of vertical clinging and leaping as opposed to quadripedal locomotion or slow climbing (lorisoid). Clinging and arm swinging (brachiation) are possible. This connection has been observed by Tattersail who saw Propitheci and Indri climbing trees with a shinning motion and descending hand over hand, while Fetter has observed arm swinging in P. verreauxi Roberts and Davidson, 1975). The pseudo - opposable hand, with its strong musculature and palmar pads provide the dominant grip for these arboreal animals. Early suggestions were that the prehensile hand was suitable for coarse gripping only, but studies are only beginning on the nervous structure of the hand and brain centers that control it. The literature indicates that greater dexterity, particularly in the case of Propithecus, is postulated. The elongated Indri hand is capable of grasping tree trunks up to 50cm in diameter. Likewise, the Indriidae foot provides a strong prehensile grasping organ whose shortness separates them from other prosimians. The cartilagenous patella with its thick tendons is especially adapted for leaping. The proportions of limbs to body length allow bipedal locomotion. Morphologically, the Indriidae, with their coordination for vertical clinging and leaping as well as bipedal locomotion on the ground, are the most specialized and evolved lemurs (Jouffroy, 1975). The teeth and alimentary system, including the specialized caecum, are adapted to a folivorious/frugivorous diet. The .position of the orbits in the skull indicate a good stereoscopic vision. It is believed that Indriidae possess color vision because they appear to identify individuals by pelage coloration. The toothscraper is used to pry bark loose which is essential to Indriidae diet. It is also used in grooming others while the toilet claw is employed by the individual to groom itself (see Behavior). The evolved ear indicates that the animal is dependent upon hearing which is borne out by its complicated communication patterns and symbolized by the laryngeal sac. The animal is also believed to have an excellent sense of smell indicated by the presence of the glands used for scent marking and as part of the' reproductive cycle. Touch is probably a developed sense indicated by the refined patterns on the palmar pads. The lack of sexual dimorphism morphologically reflects a non male dominated society which behaviorally is not aggressive compared to other primates. The Indriidae -11- M. Robinson

.ONTOGENY AND REPRODUCTION Male Genitalia The scrotum is covered with hair; the penis has small spines; and the baculum is bifurcate (A. Petter-Rousseaux, 1964). In the Avahi the scrotum is divided into two, and the penis has small scales covering it (A. Petter-Rousseaux, 1964). The urethra opening is a vertical slit at the end of the penis. In general, the testes are extra-abdominal. Scrotal volume is subject to seasonal cycles, but the testes are never completely retracted during periods of sexual inactivity. The prostate encircles the urethra, and there is a "well developed pair of Cowper's glands. In general, male and female genitalia closely ressemble the higher primates (A. Petter- Rousseaux, 1964). Female Genitalia In Avahi laniger the clitoris is long and thin with a deep vertical slit. In adults the vaginal opening remains open at the base of the clitoris (A. Petter-Rousseaux, 1964). Propithecus verreauxi has a short clitoris. The vaginal opening is probably always open, and there are scrotum-like appendages on each side of the clitoris which do not occur in Indri indri (A. Petter-Rousseaux, 1,964) . Internally the ovaries and uterus ressemble the forms of higher primates. Breeding Behavior Although there is much calling and visiting between groups of Propithecus verreauxi, they are still considered discrete groups. In late January the vulva begins to flush signalling the beginning of the pre-copulatory period (Richard,1974). Both males and females endorse each other by scent marking and urinating slightly on a branch or trunk in response to similar behavior on the part of a member of the opposite sex. There is another behavior observed by Richard which she called the "Sniff-approach and mark." The male marks the trunk just below the female's tail. He then touches her anus with his nose, then throat-marks, and finally uses the ano-genital glands to mark. Richard notes that this sequence is frequently invomplete because the female will lunge at, cuffing the male when he sniffs her anus. During the mating season, pairs or single Propitheci travel to other groups, often resulting in fights or copulation with adult females in the visited groups. This type of behavior has been observed in monkeys and chimpanzees where it proportedly prevents incest and strengthens the diversity of the gene pool of the species. During the mating season, Richard observed a breakdown in the usual dominance hierarchy allowing subordinate males to initiate aggression (Richard, 1974). Mating was completed in March. P. verreauxi has a gestation period of 130-150 days. The length of the oestrous cycle is believed to be similar to Lemur catta which, in captivity, lasts 33-45 days. Male P. verreauxi are often observed with scared noses and torn ears, much more than females, and it is believed that this is the result of fights during the mating season. Indri indri and Avahi laniger breeding behavior are unknown. Reproduction Propitheci give birth from June to August depending upon the subspecies. The newborn have their eyes open, and their heads are covered with hair, the rest of them has a sparser covering. The mother licks the infant vigorously for the first day (A. Petter- Rousseaux, 1974). The infant clings to the abdomen of its mother, head hidden in her groin. The thighs of the mother are bent to form Buettner-Janusch, 1964

128 A. PETTER-ROUSSEAUX

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I- 1C. 10. Pro)>itltecu.i if;;v<(iui. .1. \lcilln-i lii-kinj^ IK i ni4wl>orii. Hiitli OLCiirrecl u feu- 1lours !>rh>!c picture was t.ikcn. !j. Thr !;rip of the iicwliorn on tin: mother';. Ix-lK ! air. The umbilical ronl N MI!\. c. Mo'l.ci. \\illi intant lit u«'r -5 mouths.

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J The Indriidae -12- M. Robinson < ONTOGENY AND REPRODUCTION (Cont'd) Reproduction an angle; her tail is rolled up between the thighs, and, she holds her body leaning backwards to form a hollow which the young occupies. Motion is very cautious. After 30 days the infant moves to mother's back. At 45 days the infant makes tentative independent explorations. At 90 days the infant is able to make jumps of 50 cm and becomes acquainted with other youngsters. Small plaintive cries alert the mother. Young Propitheci are carried for 6 to 7 months and remain in close contact with the mother for at least a year. They appear to stay close to the mother until they are 2^-3 years old and presumably sexually mature (A. Petter- Rousseaux, 1964). Avahi laniger give birth at the end of August in Western Madagascar, At birth the infant measures 9 cm (head and body) and 7 cm (tail). They are believed to be nursed for five months. Very little is known about the reproduction of this animal and its large cousin, Indri indri. ECOLOGY. In eastern Madagascar a series of steep crests run from North to South with altitudes between a few hundred and 2,000 meters. An easterly wind prevails contributing a variety of climatic conditions to the valleys, slopes and hill sides. To the south on the eastern coast near Perinet midway between Tananarive and its port lies a dwindling, steamy rainforest. The other area to the north is colder and wetter. There are great differences in flora and fauna, and a variety of fruiting patterns. The ecology ranges from mossy wet ( undergrowth to tall straight deciduous trees with continuous canopy and on the hill crests, small stubby shapes. Vines, lichens, orchids, bamboo glades and tree-like ferns are common. The boundaries of these shrinking wilderness areas mark the only location of the shy, silently moving Indri indri. The complicated environment it makes its home is extraordinarily rich in botanical diversity (Polluck, 1975). Indri ingest enormous amounts of leaves; also bark, flowers, and fruit are essential. They take no animal protein. Each family group occupies a separate hill. They are considered territorial, seldom moving more than 600 meters a day. They are found on trees, larger vertical branches and in the forks of trees. Besides man, the Indri have no natural predators, although it is believed that the harrier hawk and fossa fossa, a fox-like endemic animal, may occasionally get an Indri infant. Also falls may damage young. Indri have no defenses except their natural stealth, their amazing locomotion habits, and the coloration of their pelage which allows them to melt into the light filtering through the trees where they sit motionless for up to 18 hours. A similar environmental niche is occurpied by the smaller Avahi whose nocturnal behavior and diet closely replicate the larger Indri. Predation possibilities are the same. The animal appears to fill a niche in the rainforest ecosystem of the Northwestern coast and, presumably, the eastern coast where it was once found. The Indriidae -13- <• M. Robinson ECOLOGY. The versatile and richly subspeciated Sifaka is found sympatric with the other Indriidae and sympatric with other lemurs in the dry south and southwestern didierea forests. The didierea is a tree endemic to Madagascar yet similar to large cacti in the southwestern U.S. Propithecus verreauxi verreauxi makes its home, clinging vertically to these spiny stalks, and tamarind trees of which it is very fond. "These animals are the other half, of the equation of the spiny deserts the reason for the plants' defenses. These animals, with the sun's heat and the rain clouds that stop at the mountains, have formed the geometry of thorn and thorn-shadow, just as the plants have shaped the forces of sifaka muscle and bone and the trajectory of that gleaming leap (Jolly, 1980). Richard has observed that regional, seasonal and local variation was notable in the diet of P. verreauxi. Four trees were identified in the sifaka diet and available in each of her four study sites from the south and up the western coast. Each predominated in sifaka diet in areas where it was most plentiful, although the diet included differing percentages of the other trees. Each area had a different subspecies. Where there were fewer species of trees available, the animals fed on a wider variety of plants (Richard, 1974). No indriidae has been observed drinking water. Presumably they get their required moisture from their diet. These animals have until very recently been impossible to maintain in captivity primarily because their diet was not understood. Some substitutes are permitted such as rice, guava, bananas, however they must have bark. Indriidae are found in captivity in the zoo at Tananarive and on the zoo's farm. There were no available longevity records for Avahi, and Propitheci have been able to live seven years in captivity. Both species reproduced once. The longest recorded captivity for an Indri was 30 days when all six captives died. That was in the 1930's, and, to my knowledge, it has not been attempted again. The Indriidae, and all lemurs, are protected by law, and it is illegal to take them from Madagascar. Other lemurs, such as the ringtail lemur, have been raised in captivity without the dreadful fatality records related to Indriidae. Perhaps it is simply the highly specialized diet and locomotion habits. jolly hints that a psychological apathy, a shock mechanism, may overcome the animal when captured which „- may set off an unknown balance contributing to its demise. I*J*& ^ "Captive sifaka simply look down and never look up again" (Jolly, 1980). Jolly, 1980

i

Lavalohalika (5)

Avahi laniger

Indri indri

Propithecus diadema

Mount Hiaraka (3) Avahi laniger? Nosy Mangabe(4)

Bay of Antongil (3)

Maroantsetra(3) Propithecus spp.

•\Mahambo Village (6)

Ampasambazimba Swamp (7) Forest Station (6)

Perinet Reserve (6)

Propithecus spp. mi THE FORESTS OF MADAGASCAR Places visited are followed by chapter numbers

savanna and steppes dense rainforest HI savoka mountain forest LJ dry deciduous forest Tulear(1 tiiil spiny desert Sept Lacs (11) SCALE

(9)

?ropithecus verreauxi

'J from Humbert tinJ Cours-Darne 7965 The Tndriidae -14- N. Robinson

BEHAVIOR. Avahi laniger Normally the Avahi spends the day rolled up like a ball in the foliage away from the trunk. It has been photographed huddling in what is believed to be a family group of two to four members. In order to keep track of group members when moving about in the dark it scent-marks branches (Burton, 1969). It communicates with grunts, soft whistles and high pitched,. prolonged whistles which are nearly inaudible to humans (Napier, 1967). Very little more is known about its behavior which has not already been discussed. Like its larger relatives, its resting time is spent in the forks of trees (other than sleeping time). Martin has suggested that, like the higher primater, the Indriidae lost the ability to nest when they began carrying their young with them. Also this family has grown too large to nest with any kind of grace which may be the reason why the Avahi is the only nocturnal lemur which does not employ some sort of nest. Indri indri Like the Avahi the Indri has been observed in what are believed to be family groups of two-four individuals. Jonathon Polluck who recently spent 15 months in Indri country observed larger units in areas which were disturbed by foresting activity and individuals fled, joining with other Indri. The groups he observed had, for the most part, an adult of either sex and either an infant or a youngster, 1-3 years old. Indri are believed to be monogamous. There is no sexual dimorphism and sexing is very difficult unless the animals become habituated to the observer. Indri are usually sympatric with Propithecus diadema and Avahi laniger; it is postulated that this situation is so ecologically timed so that the animals eat leaves of different ages on the same plant but at different times. The most characteristic behavior of Indri indri is its pattern of vocalization. The tendency to vocalize is dependent upon the season, weather, and proximity to other groups (Polluck, 1975). There can be silence for days and then up to seven call sessions a day. The calls seem to be of two types (Polluck, 1975); repeated horn blasts apparently uttered by disturbed or isolated individuals, and a bark or series of barks, followed by long, modulated howl uttered by all family members (Petter and Peyrieras, 1975). Jolly describes the Indri's song like this: "A wailing rose from the hill, a rising tone like an air-raid siren, pitched soprano, ultrasoprano, and still rising. Several voices began together, with a barking roar, and then rose, false thirds apart so you yearned for a piano tuner. P'irst one voice, then another broke off, leaving one alone to continue the downward half of the siren's note. Then, as this group died away into silence, they were answered by a second, and a third group, the wails echoing over the water, reflecting one another as the still river mirrored the hill. An indri female sings through the whole song, the male for only a part, juveniles for still less. Each animal sings in its own voice, so the echoes and reechoes told each group where every indri was upon the hill. Eerie and beautiful, yet the only The Indriidae -15- M. Robinson

BEHAVIOR. Indri indri (cont'd) human cry which can compare is a child in extreme hysteria. The kind of sound which we make, with larynx squeezed rigid and emotion out of all control is, for the indri, a song. Polluck notes that this cry can be heard by humans 1500-2000 meters away, and that the frequency is between 500 to 6000 Hz. A typical singing session is thirty minutes. He also believes that Indri perceive calls from 3000 meters away. He does not know what the call means but has suggested that it is an attempt to communicate with other individuals in the same territory, possibly to declare occupation or reunite dispersed individuals with their group or announce the reproductive status of individuals. I have heard this cry on tape and there is a tremendous sense of bittersweet ecstasy related which makes all of these good explanations seem rather bland. Indri bark at aerial predators such as hawks, also airplanes and thunder (Polluck, 1975). They appear to "hoot" at ground predators like Fossa fossa or humans. Indri hum to indicate immenent movement much in the same way that their more energetic relatives, the Sifakas, coo before leaping. Indri sleep at a height of 30-100 feet in nonspecific trees. No more than two sleep together; infant with its mother and the next to youngest sleeps with the adult male. Upon waking the animals will briefly feed on the nearest leaves and then descend ( to urinate and defecate in unison (Polluck, 1975). It has many sleeping sites within the territory and the disposition to travel to a particular one seems dependent upon proximity when the animal wishes to retire. It eats 63 plant species. Two hours of each day are spent eating fruit. The fruit is picked with the teeth, transferred to the hand, and eaten from the hand. Feeding continues all day like the sympatric lemur, Propithecus diadema. Indris are sometimes awake no more than 5-6 hours during the rainy season. Grooming sessions follow eating. At times the animals were observed resting for 18 hours a day, occasionally moving because of a noise or to scratch with the toilet claw. Polluck believes an Indri family lives in a territory of 17- 18 hectares. Where territories overlap, singing duels occur. Marking behavior is also observed after border conflicts. Although no fighting has ever been observed, animals do not eat and are restless after a border singing duel. It is unclear how territories are decided. Indris practice "allogrooming" which is repeated alternate caressing concentrated on partner's head and neck. The amount of time spent in this activity as well as grooming young has led to the speculation that the animals are very affectionate with each other. Social displacement is followed by disturbance vocalizations from both the agonistic party (bite, kick, or wrestle for preferred sleeping or eating place) and the nonagonistic submissive party. Polluck describes "grunts," "kisses," and "wheezes" with increasing anxiety as the animal becomes frightened or nervous. Young indri play wrestle, allogroom, and social displacement is a part of their play bouts. Adults permit young to steal food. Sexual behavior and marking behavior is very much like that already The Indriidae -16- M. Robinson

BEHAVIOR. Indri indri (cont'd) described for Propithecus. Infants adapted to vergetation diet between 2-6 months. Between 6-8 months the infant must keep up with the mother in the trees, often sustaining falls of 30 feet. After 8 months, youngster has learned how to land (Polluck, 1975). The youngster stops nursing after 1 year old. Learning appears to be memorizing edible plants by observing adults. A close relationship with the mother is maintained through the second year. Individuals keep in sight of each other when feeding, even when in different trees. It is not known how long Indri live. Propithecus verreauxi. The larger Propithecus diadema has not been studied that I am aware of. There are two excellent studies of Propithecus verreauxi, those by Alison Jolly in 1966 and Alison Richard, 1975. Those behaviors which are akin to all Indriidae will not be repeated here; instead I will record only those behaviors attributed solely to P. verreauxi. After the troop awakens they move 20-50 meters to the sunning trees (Jolly, 1966). At 8:00-9:00 AM they move 20-50 meters to feed. This process is repeated at noon before a siesta. Between 2:00 PM-4:00 PM they move to the evening feeding spot, settling down to sleep between 5:00 - 7:00 PM. P. verreauxi sleep in crotches of trees about 13 meters off the ground. If sleeping with another animal,one holds a vertical branch while the other holds the first animal (jolly, 1966). They may return to the same tree for 3-4 nights then move on to another sleeping tree in the same territory. Their waking behavior ressembles that of Indri indri. Depending upon the weather, sifakas generally sun themselves almost immediately. This behavior is believed to be related to an inefficient body temperature problem. A sunning tree consists of large branches where the animals can lean back, often without hanging on, and expose their dorsal sides to the eastern sun. When thoroughly warmed, the animal turns around and exposes its back. As they warm, sifakas begin grooming themselves, scraping their fur with the tooth comb, alternately licking it. This activity finishes with a good scratch with the toilet claw, carefully finishing with an ear cleaning. At this point they groom each other and play. Unlike the indri, they urinate and defecate one by one. Richard observes that there are regional variations in behavior between groups, seasonal variation, and local variation. Groups ranged in size between 3-13 individuals, and the sexual ratios varied greatly so no model for group composition was ever established. Group encounters were more common among animals living in the northern territories, yet they were less formal or stylized than Jolly's observations in the south. "Territorial 'battles' are formal affairs composed of leaping, staring, and scent-marking with very low growls or in silence. Invading troop members stay in close formation, move hesitantly, smell and scent-mark the branches. If unopposed, they may spread out to feed but remain alert and on guard. If the resident troop appears, the invaders bunch together, face them, and scent-mark. The Tndriidae -17- M. Robinson

BEHAVIOR Propithecus verreauxi (cont'd) "The residents hop very rapidly toward the invaders "without stopping to scent-mark, unless they too are very near the edge of their territory. The invaders wait until the residents are almost upon them, then hop backward toward their own domain. The troops often seem to mix, with animals leaping about in chaos. Each group, however, keeps its own orientation, the troops facing their goals like sets of opposing chessmen. Rivals may even land back to back in the height of battle as each faces outward from his territory. At the climax the outraged residents may sifaka softly. A territorial battle may be very beautiful, since everything depends on a fast, formal pattern of movement, each animal occupying sections of tree rather than opposing individuals of the other troop. Each tense leap, therefore, carries an attacker toward a particular undefended area of tree, not into contact with an enemyV(Jolly, 1966). Again, it is not understood how territorial borders are formed, but attempts to drive a troop out of its territory were always unsuccessful, the animals responding as if they had hit an invisible wall and lept back into the territory. Battles generally occur over a preferred food source. The home range is considered 1-2 hectares, and the troop will visit most parts within 10-20 days. Sifaka also have an intricate number of calls. Flying predators warrant either a bark or a roar. The roar is made head flung back and mouth pursed into an "o". The animal exhales three or four times with a blast that carries two troops away. Propitheci run from humans only if chased or if hunted before (presumably). When spotting a human, the sighter clicks deep in the throat. The troop will leap in unison approaching the human (also any suspected ground danger). One animal will begin to "sifaka" the noise which gives them their common name. The closest English translation for the sound is "shi-FAHK" which bubbles up like a groan and ends with a click. The animals stare while calling. All Propitheci have a variation of this sound, but the emphasis and delivery are species-specific. A chorus of * "sifakaing" is said to be quite unnerving. An ordinary bout of "sifakaing" lasts between 5 and 45 minutes. Between "sifakas" the animals wheeze and growl, punctuating the calls with a head jerk and never blinking. They will come as close as 3 - 5 meters, sometimes touching each other on the hands and licking noses, always keeping together. As they become more excited the sifakas are prolonged, ending in an explosive click. If the human returns their stare, they become unnerved and retreat in troop formation hopping backwards, sifakaing until out of sight (Jolly, 1966). Petter reports hearing a troop sifaka for two hours. Jolly believes this calling and accompanying rituals to be a mobbing technique used with ground predators in general. Propithecus verreauxi lives in a sympatric relationship with Lemur catta which it ignores. Troop members demonstrate some aggressive behavior when individuals are competing for a food source, or resting spot, over infants, if males approach a female outside the breeding season, and The Indriidae -18 M. Robinson

BEHAVIOR Propithecus verreauxi (cont'd) if a female is approached by a juvenile male after losing an infant. Encounters include "spat" vocalizations, staring, cuffing, lunging, and biting on the back of the neck or limbs accompanied by a "cough" or "hack,. (Richard, 1975). Sometimes an aggressor will force another individual to groom him in an activity called "collaring." The aggressor puts an arm around the aggressees neck and forces his nose into the fur of his shoulder. Submissive gestures include high squeeks in rapid succession, departure from the contested site, a purring noise, and a strange grin. The nature of the relationship seems to govern the reaction (Richard, 1975). Sifakas allogroom like the Indris. They will wrestle, sitting opposite each other, sparring and trying to catch the other off guard. The object is usually genital grooming (Jolly, 1966). They will play by ptitting their feet together and pedal round and around in opposition like children playing bicycle. They are fond of chasing each other. Contact animals, like all lemurs, sifakas are too big to "clump." Therefore, they will form locomotives, one animal sitting behind another, belly pressed against the back of the first, huge leaping legs enclosing the one in front on either side. Jolly has observed that this is a position of maximum contact for big long-legged animals on a branch. Infants are greatly admired by all troop members, Mothers are extremely intolerant of this attention. Grooming is the major social interaction intended by the infant attention, and it will learn to groom troop members by the time it is 2 months (Jolly, 1966). GENETICS. The chromosome count for the Indriidae has been touched upon previously. Propithecus hemoglobins, on starch gel electrophoresis, show a single Hb band seen with mobility equivalent to human A serum (Napier, 1967). Included is a chart with similar results from experiments done by the Buettner-Janusches, 1964. Very little is known of the genetical make-up of these animals. Even the phylogeny of sifakas is not at all understood. Observers have reported changes in fur patterns as young mature which might suggest more contact among subspecies than hitherto expected, or an adoption mechanism, like chimpanzees, when subspecies are sympatric. REMARKS. In 1866 Alfred Grandidier came to Madagascar in search of lemurs. He had read Flacourt and many accounts by various adventurers about the "Island of the Moon," the "Land of the Roc." Madagascar became his life's work culminating in a 27 volume series entitled Histoire physique, politique et naturelle de Madagascar. He died in 1921 never seeing the finish of his travails (Tattersall, 1972). Some of the plates from his work are replicated in this study as they remain accurate. Many have come to look at the lemurs since then. David Buettner-Janusch, 1964

•Origin

r

i 8 10 FIG. 2. Hemoglobins of Prosimii and Homo (photograph of starch gel). Condi- tions of electrophoresis and staining are the same as those given in Fig. 1. (1) Human hemoglobins A and F. (2) crassicauilutiut, (3) Li-ninr cutta, (4) Hapalemur griscus, (5) Propitheetis rerrcauxi coquercli, (fi) Lemur mongoz, (7) /.,. rarifgiiinx, (8) L. macaco, (S'l /,, ftilr.im, and (10) same as sample 1. The Indriidae -19- N. Robinson

REMARKS. Attenborough came on a zoo specimen collecting trip in the early sixties. He spoke of Madagascar as the lumberyard of the world where "outmoded models were stored." Prior to 1970, Fetter's a'.d Jelly's field studies .were the only published works on the behavior and ecology of any prosimians. In the past decade research on primates, in general, has exploded, and the latest studies of prosimians, hitherto thought to be to unimportant to bother with, are consistently and inexplicably demonstrating behavior patterns considered sophisticated. When I was studying physical anthropology in the late sixties, the departmental philosophy was that the study of all animaB, especially primates, was permis^able only if the objective was to demonstrate a new or substantiate an old theory about the origin of man and his behavior. In the literature I read in order to do this research I sense a profound change in the -outlook of both physicial anthropologists and biologists. This is attributable to the environmental approach to studying nature, I believe. Hitherto the animal was measured as he/she stacked up to humans (measured by humans). Now, perplexed by our supremacy and always attempting to explain or apologize, we have returned to the truth about animals and plants. We may never have the wit to understand natural interactions, but at least we now acknowledge their complexity, and the fact that we cannot explain ( everything in terms of human outlook. Those who have studied sifaka and indri know how uniquely these animals belong to the ecosystem. The complexity of that relationship is only begun to be known. If parallel evolution has occurred on Madagascar, and the lemurs are the monkeys of that island, then their ingestion of the native vegetation is an essential part of the survival of that vegetation. Malagasy officials are sensitive to the value of the island's natural heritage. They have passed laws protecting the lemurs (but not enforced them)} there are educational opportunities offerred (but not to the natives whose only protein may be a sifaka), and there are laws regulating any export of lemurs. Malagasy officials have set aside 12 nature reserves, 2 national parks, and 25 zoological reserves, all of which are inadequately supervised. Most funding to protect the native animals comes from overseas. Madagascar faces the classic problem of developing nations; how to feed the growing, starving population which is at poverty level, educate them to revere the uniqiieness of their natural heritage, and respect that heritage enough to co-exist with it. It would be easier if, like the Yemen government restoring the Arabian oryr.x to its original home, one had the money from oil to pay the locals not to kill the animals. There are two very hopeful aspects (both penniless) about this study. The first is a sense that the study of animals ( is becoming less anthocentric; that the justification of studying animals may be their own complexity. It is interesting to find a field where scientists admit that they simply do not understand their subjects. In far more romantic tones, yet not a bit less accurate than the Indriidae research accounts I read is the statement The Indriidae -20- '•-:•;;:_-. M.Robinson

REMARKS, by Henry Beston. "We need another and a wiser and perhaps a more mystical concept of animals. Remote from universal nature, and living by complicated artifice, man in civilization surveys the creature through the glass of his knowledge and sees thereby a feather magnified and th whole image in distortion We patronize them for their incompleteness, for their tragic fate of having taken form so far below ourselves. And therein we err, and greatly err. For the animal shall not be measured by man. In a world older and more complete than ours they move finished and complete, gifted with extensions of the senses we have lost or nev er attained, living by voices we shall never hear. They are not brethren, they are not underlings' they are other nations, caught with ourselves in the net of life and time, fellow prisoners of the splendour and travail of the earth." What does this have to do with the big lemurs who have lived in a world untroubled by predators and apparently have established com plex communities and behaviors that hitherto have been attributed to animal communities facing constant predation or aggression? These animals are the big kids on the block, yet they are not aggressive, and, in human terms, appear to be defenseless, social, gregarious, and successful. Those researchers who have spent any amount of time with them have filed dry, conscientious, thorough reports, yet when one goes behind the reports, one discovers that the statement set forth by Beston in 1928 is applicable. Jonathon Polluck tried to outwit the Indris for 15 months in a dripping rainforest, Alison Richard ran after Propithecus verreauxi for three days to get a picture of itj Alison Jolly lept to strangle a local >{ho mortally wounded a Propithecus verreauxi . Besides the wonderment of ecological necessity, besides exotica which Madagascar presents over and over, besides proported evolution about the study of animals, I am interested to see an interest emerging for the animal for its own sake. Contemporary ecologists and environmentalists are finally understanding, whether it be in Madagascar or in Southern Putjet Sound, that we are our own survival, and our behavior will indicate how much we value that environmental concept. LITERATURE CITED. Altmann, Stuart A. Social Communication Rmonq Primates. Chicago, University of Chicago Press, 1967. Attenborough, David. Bridge to the Past; Animals and People pt Madagascar. New York: Harper, 1962. Battistini, Rene and G. Richard-Vindard( ed . ) , Bioqeography and ecologf* of Madagascar. The Hague: Dr. W. Junk, 1972. <3ffSns*r H&/JA"Y. -r/Jf-QL>n~A.*ie>5f *&£*£ •*>(•*> yfe^V- •/ ^«"V

Napier, John Russell and Napier, P. H. A Handbook of Living Primates; Morphology, Ecology, and Behavior of Non Human Primates. New York: Academic Press, 1967. Nelson, Harold D. Area Handbook for the Malagasy Republic. U.S. G.P.O., 1973. Petter, J. J. "Ecological and Behaviorial Studies of the Madagascar Lemurs in the Field," Ann. N. Y. Acad. Science, 102, 1962, 267-281. "Madagascar Lemurs : Isolated Primates'.' Natural History . 72( 3 ); 22-27 . "Order of Primates: Sub-order of Lemurs," Bicqeoqraphy and ecology in Madagascar. Hague: "Junk, M972 . and Peyruras. A. "A Study of Population Density and Home anges of Ind.ri indri in Madagascar," Prpsimian Biology, 1974 . - Pollock, Jonathon. "Field Observations on Indriindri ; ' P&&SS, a preliminary report. " Lemur Biology, 1975. Richard, Alison F. "An Analysis of the Social Behavior of Three Groups of Propithecus verreauxi . " Lemur Biology, 1975 ••I'lntra-Specific Variation in the Social Organization and Ecology of Propithecus verreauxi," Folia Primatologica 22tl78-207 (1974). ( "Patterns of Mating in Propithecus verreauxi . " Lemur Biology, 1975. Roberts, David and Davidson, Isobelle. "The Lemur Scapula," Lemur Biology, 1975. Rumpler, Yves. "The Significance of chromosomal studies in the systematics of the Malagasy Lemurs," Lemur Biology, 1975. Saban, Roger. "Structure of the Ear Region in Living and Subfossil Lemurs." Lemur Biology, 1975. Schwartz, Jeffery H. "Development and Eruption of the Premolar Region of Prosimians and Its Bearing on Their Evolution," Lemur Biology, 1975. Szalay, Frederick S, and Delson, Eric. Evolutionary History of the Primates . New York: Academic Press, 1979.

Tattersall, Ian. "The Lemurs of Madagascar1.' Discovery 7(1) Fall 1971. 27-36. "Of Lemurs and Men," Natural History 81 (3): 32=43 March 1972. "Subfossil Lemuroids and the Adaptive Radiation of the Malagasy Lemurs." Trans . N. p. Acad. of Science, 1972, 314-324. Tuttle, Russell H. led.) Primate Functional Morphology and Evolution. The Hague:Mouton Publishers, 1975. Socioecology and Psychology of Primates. The Hague :Mouton, 1975. The lemur is a lowly brute, Its primate status, some dispute. He has a damp and longish snout, With lower front teeth hanging out. He parts his hair with his comb-jaw, And scratches with a single claw, That still adorns a hinded digit, Wherever itching makes him fidget. He is arboreal and omniverous, From more about him, Lord deliver us.

Prof. Ernest "Hootin™ Hooton, Harvard University

(Bourne, 1974)

C