Surveys in the forests of the Taita Hills yielded a new primate record for Kenya. Based on direct observations and tape recordings of its vocalizations, this primate is identified as a dwarf galago Galagoides sp. Identification to the species level is not possible at this stage as molecular data are not available, and more morphological and vocalization data are required. The vocal repertoire of the “Taita mountain dwarf galago” is qualitatively different from other known populations of dwarf galagos, including the mountain dwarf galago Galagoides orinus and the Zanzibar galago Galagoides zanzibaricus cocos. The Taita mountain dwarf galago might represent a hitherto unknown subspecies, or even species. The possible identity of the Taita mountain dwarf galago is briefly discussed in terms of biogeography. We also confirmed the presence of Garnett's small-eared galago Otolemur garnettii lasiotis and present biometric measurements from trapped animals.
THE TAITA MOUNTAIN DWARF GALAGO GALAGOIDES SP: A NEW PRIMATE FOR KENYAAndrew Perkin⟨sup⟩1⟨/sup⟩, Simon BearderNocturnal Primate Research GroupOxford Brookes University, UKbwanakomba@yahoo.co.ukThomas M. Butynski⟨sup⟩2⟨/sup⟩Zoo Atlanta's Africa Biodiversity Conservation ProgramNational Museums of KenyaP.O. Box 68200, Nairobi, KenyaTButynski@aol.comBernard Agwanda, Benny Bytebier⟨sup⟩3⟨/sup⟩National Museums of Kenya, Taita Hills Biodiversity ProjectP.O. Box 40658, Nairobi, Kenyarisky@email@example.comABSTRACTSurveys in the forests of the Taita Hills yielded a new primate record for Kenya. Based on direct observations and tape recordings of its vocalizations, this primate is identified as a dwarf galago Galagoides sp. Identification to the species level is not possible at this stage as molecular data are not available, and more morphological and vocalization data are required. The vocal repertoire of the "Taita mountain dwarf galago" is qualitatively different from other known populations of dwarf galagos, including the mountain dwarf galago Galagoides orinus and the Zanzibar galago Galagoides zanzibaricus cocos. The Taita mountain dwarf galago might represent a hitherto unknown subspecies, or even species. The possible identity of the Taita mountain dwarf galago is briefly discussed in terms of biogeography. We also confirmed the presence of Garnett's small-eared galago Otolemur garnettii lasiotis and present biometric measurements from trapped animals.⟨sup⟩1⟨/sup⟩ Current address: 39A Rickman Close, Woodley, Reading, RG5 3LL, UK⟨sup⟩2⟨/sup⟩ Conservation International, c/o IUCN, P.O. Box 68200, Langata 00200, Nairobi, Kenya⟨sup⟩3⟨/sup⟩ Current address: Biochemistry Department, University of Stellenbosch, Private Bag XI, 760 Matieland, South AfricaINTRODUCTIONThe Taita Hills (03° 20' S, 38° 15' E) are located in southeast Kenya, 25 km west of Voi and 165 km from the Indian Ocean in Taita-Taveta District, Coast Province. The Taita Hills rise out of the Tsavo Plains at 600-700 m to reach 2208 m at Vuria Peak. The forests of the Taita Hills are submontane and montane, and are described as 'upland moist' or 'upland mist forest' (Beentje, 1988). The climate is moderated by altitude and influenced by the Indian Ocean. Annual rainfall above 1,400 m exceeds 1,500 mm. In addition, heavy mists occur throughout much of the year (Beentje, 1988).Due to human influences, the indigenous forest in the Taita Hills is highly fragmented and all remaining forest fragments are small. The biggest forests are Mbololo (168 ha), Ngangao (92 ha), and Chawia (50 ha). All the other fragments are less than 5 ha (Beentje 1988, Bytebier 2001). Details on the vegetation, history and ecology of the Taita forests can be found in Beentje (1988), Wilder et al. (1998), and Chege & Bytebier (submitted).The Taita Hills, together with Mount Sagala and Mount Kasigau, form the northern-most part of the Eastern Arc Mountains. These indigenous forests are of high conservation value since they contain an unusually high proportion of threatened and endemic animals and plants (Beentje, 1988; Lovett & Wasser, 1993; Collar et al., 1994; Brookes et al., 1998a,b). Together with the coastal forests of Tanzania and Kenya, they are ranked as one of the world's 25 "Biodiversity Hotspots" (ICBP, 1992; Mittermeier et al., 1998; Myers et al., 2000).Despite the importance of the Taita Hills forests for the conservation of biodiversity, only a few mammal and no galago surveys have been undertaken. Loveridge collected three small galagos from Mt. Mbololo, Taita Hills, in 1934. These were deposited with the Museum of Comparative Zoology, Harvard University (Allen & Lawrence, 1936; Lawrence & Washburn, 1936). Loveridge and his colleagues were able to differentiate between the small, forest-dwelling, Galagoides spp., and the large, woodland-dwelling, Galago spp. (Allen & Lawrence, 1936; Lawrence & Washburn, 1936). Two of the specimens (MCZ 31723 and MCZ 31725) were identified as northern lesser galagos Galago senegalensis braccatus based on pelage, and body and cranial measurements (Lawrence & Washburn, 1936). Allen and Lawrence (1936) state that these animals have "...the outer side of the limbs and the middle of the belly washed with pale yellow." This is the typical pelage coloration of G. s. braccatus. The body measurements of MCZ 31724 (female) and MCZ 31725 (male) (Allen & Lawrence, 1936) are as follows:head/body length: 160 mm, 170 mm;tail length: 170 mm, 240 mm;ear length: 30 mm, 42 mm;hindfoot length (male only): 60 mmThese measurements lie within the range for G. senegalensis, and are generally outside of the range for any of the dwarf galagos (Galagoides spp.) (Olson & Nash, in press).It is unclear where exactly on Mt. Mbololo each of the galagos was collected by Loveridge. Allen and Loveridge (1936) state that, "The male Galago crassicaudatus lasiotis was shot within a few hundred feet of the male G. s. braccatus in the rain forest capping the mountain at 4300 feet." From this statement, it is not clear whether this G. s. braccatus (MCZ 31725) was collected within forest or not. Note that 4300 ft (1,300 m) is about half way up the slopes of the Taita Hills. Today, most of the land at this elevation is under agriculture. Where forest is present at this altitude, it is classified as "submontane". This observation is interesting since, during our study, we did not find G. s. braccatus either within or outside of forest on the mid-altitude slopes of the Taita Hills. It is not uncommon, however, to find G. senegalensis at this elevation over much of Kenya (see below). A third G. s. braccatus (MCZ 31274) in the same series was taken from woodland at the "Tsavo River" at the base of the Taita Hills. We also observed G. senegalensis in woodland at the base of the Taita Hills (although at low densities). There is no information in Allen and Lawrence (1936), or in Lawrence and Washburn (1936), that indicates or even suggests that any of the three small galagos collected by Loveridge in the Taita Hills in 1934 were species other than G. s. braccatus.The other two specimens taken from the Taita Hills are labelled Galago crassicaudatus lasiotis (specimen numbers; MCZ 31721 and 31722) (Allen & Lawrence 1936). Subsequent taxonomic revisions have renamed these as Otolemur gamettii lasiotis and placed the name Galago crassicaudatus lasiotis in the synonymy of Otolemur gamettii (Schwartz, 1931; Allen 1939; Swynnerton & Hayman, 1951; Hill, 1953, Olsen, 1979, Grubb et al., in press).The most recent faunal list (Beentje, 1988) mentions the occurrence of the large-eared greater galago Otolemur crassicaudatus. However, Kingdon (1997) and Nash et al. (1989) suggest that the large galago in the Taita Hills may be Garnett's small-eared greater galago Otolemur gamettii, by virtue of the species' preference for moist forests (whereas 0. crassicaudatus occurs in dry woodland habitats). Based on skin specimens, Groves (2001) identified the greater galago in the Taita Hills as O. g. lasiotis.Recent research, based on differences in vocalizations, reproductive anatomy, and genetics, indicates a greater diversity of galago species than previously realised (Masters, 1988, 1995; Nash et al., 1989; Bearder et al., 1995; Honess, 1996; Bearder, 1999; Groves, 2001). Three new galagos for East Africa have recently been described: mountain dwarf galago Galagoides orinus, Rondo dwarf galago Galagoides rondoensis, and Udzungwa dwarf galago Galagoides udzungwensis (Honess & Bearder, 1996). However, it now appears that Galagoides udzungwensis is conspecific with Galagoides zanzibaricus (A. Perkin, unpublished data). A fourth, Grant's galago Galagoides granti, was reassigned species status (Honess & Bearder, 1996; Grubb et al., in press) after Thomas & Wroughton (1907) first described the form. Grant's galago is, however, also considered to be a subspecies of G. zanzibaricus by some authors (Olson, 1979; Jenkins, 1987).Since other Eastern Arc Mountains sub-montane and montane forests usually contain both O. gamettii and G. orinus, the possibility that a dwarf galago might also occur in the Taita Hills was considered. Several authors (Nash et al., 1989; Dorst & Dandelot, 1990; Kingdon 1997) suggest that G. senegalensis might be present in the Taita forests by virtue of its extensive range. However, we believe this is unlikely as G. senegalensis is only known to occur in Acacia, Isoberlina and Julbemadia woodland, Cynometra thicket, and certain montane forest margins, as is the case on Mount Elgon (L. Ambrose, unpublished data.) and Mau Forest (T. Butynski, unpublished data), but not in closed canopy moist forest (Nash et al., 1989). Several specimens labelled as G. senegalensis in the mammal collection of the National Museums of Kenya were indeed collected in the Acacia-Cynometra thicket in the Voi and Taveta plains at the base of the Taita Hills at 700m. There are, however, two species of forest dwarf galagos, G. orinus and G. zanzibaricus, with ranges, which potentially extend to the Taita Hills. G. zanzibaricus cocos occurs along the lower Tana River and the coastal forests of Kenya and north-eastern Tanzania (Groves, 2001, A. Perkin & T. Butynski, unpublished data) between 0 and 300 m. G. orinus is restricted to the Eastern Arc Mountains between 650 and 2,400 m (Honess, 1996; Butynski et al., 1998; Perkin, 2000a).We conducted surveys for galagos in the Taita Hills as part of a wider study to assess the taxonomic, biogeographical and conservation status of galagos in the Eastern Arc Mountains and Coastal Forests of Tanzania and Kenya. We concentrated on the two largest forest fragments, Mbololo and Ngangao, which were surveyed from 8 to 23 July 1999, and from 18 to 27 July 2000. This paper presents our findings.METHODSWe walked along paths from 18:30-23:30 h (or later when weather permitted), and from 05:00-06:00 h, and observed galagos and other animals with the aid of battery-powered torches and binoculars. Many nights were windy, wet and foggy, which affected the ability to listen for and record calls, and possibly affected the calling behaviour of the galagos. Notes were taken on all galagos sighted and/or heard, forest strata used, foods eaten, and support types used.In the field, galago species are most easily identified by their vocalizations since each species has a distinctive repertoire of 10 or more loud calls (Zimmermann et al., 1988; Zimmermann, 1990; Masters, 1991; Bearder, 1999). Mature adult galagos are known to make vocalizations in the context of vocal advertisement to keep companions together, to keep rivals apart, and to warn kin of danger (Bearder & Doyle, 1974; Bearder, 1999). Young galagos up to maturation are not known to make loud calls, particularly in the context of advertising (Bearder & Doyle, 1974; Courtenay & Bearder, 1988; Zimmermann et al., 1988).We used a Sony WM-C6C audio tape recorder and Senheiser K6-ME66 directional microphone to record vocalizations.Chardonneret box traps (Charles-Dominique, 1977) were used to trap animals. These were baited with bananas and 'mnazi' an alcoholic drink locally brewed from coconut tree sap. Insects and geckos were also used as bait. Traps were set at a variety of heights (up to 5 m) in places where dwarf galagos were seen. All galagos trapped were removed, examined and measured, and kept quiet and safe in the trap until release the next evening. Length measurements, body mass, pelage, penile morphology, and face 'mask' were used to identify the captured specimens (Anderson, 1998, 1999; Bearder, 1999).RESULTSGarnett's Small-eared Greater Galago Otolemur garnettii lasiotisO. garnetti were encountered every night. They were abundant in the indigenous forests, in plantations of exotic trees, and on farmland from 1,500 to 1,900 m. O. garnettii utilized branch support sizes greater than 3 cm in diameter, and were seen and heard at all levels above 1 m from the ground.The overall encounter rate from 91 h of total survey time, based on both observations and vocalizations, was greater than five O. gamettii/h, and was higher on the edge of forests than in the interior. All individuals seen and trapped were identified as O. garnettii lasiotis. They were morphologically consistent with the description of this subspecies as presented by Groves (2001). That is, they are, "lighter and more greyish than in nominotypical O. g. garnettii; end of tail generally only slightly darker and often sharply white at the tip itself; underside grey-white rather than yellowish".Seven O. garnettii were trapped in Mbololo (table 1). Males (mean 916 g, range 820- 990 g) were notably larger than females (mean 755 g, range 650-815 g). Another four were trapped in Ngangao but not measured. The pelage of O. g. lasiotis in Taita seemed lighter in colour than the O. garnettii lasiotis in the coastal forests. The gross morphology of the penis of the animals examined (n=4) is consistent with other populations studied in the field (Honess, 1996, A. Perkin, unpublished data). Microscopic analysis of individual penile spines can reveal taxonomic differences (Dixon, 1987; Anderson 1998), but this was not possible on live animals in the field. In O. garnettii, the spinal pattern, the way the baculum protrudes from the glans penis to be the most distal point of the penis, and the size and shape of the penis were consistent with those drawn by several authors (Hill, 1953; Dixson, 1987, 1989; Kingdon, 1997; Anderson, 1998). This compares with the penis morphology of O. crassicaudatus where the spinal pattern differs, the glans penis protrudes only slightly and is not the most distal point, and the distal part of the penis is more bulbous (Dixon, 1987).The following calls made by O. garnettii, were tape-recorded: "cries", "squawks", "trailing calls", and "cackles" (Bearder et al., 1995; Honess, 1996; Bearder, 1999).Table 1. Biometrics of seven Gamett's small-eared greater galagos Otolemur garnettii lasiotis trapped in Mbololo Forest, Taita Hills, KenyaMeasurement /SexMMMMMale mean (range)FFFFemale mean (range)Males & females mean (range)Weight (gm)990910820945916 (820-990)815800650755 (650-815)847 (650-990)Head-body (mm)280280270350295 (270-350)280291280284 (280-291)290 (270-350)Tail (mm)350340330340340 (330-350)320314323319 (314-323)331 (314-350)Hind-foot(mm)9094859090 (85-94)82888284 (82-88)87 (82-94)Ear (mm)5443464647 (43-54)47464546 (45-47)47 (43-54)Taita Mountain Dwarf Galago Galagoides sp.Dwarf galagos were observed on 12 occasions in Mbololo between 1,600 and 1,800 m, and on 10 occasions in Ngangao between 1,750 and 1,900 m. They were seen in indigenous forest, between 2 and 30 m above the ground utilizing supports ranging from small vertical saplings (1-4 cm diameter) to large tree trunks (⟩20 cm diameter). The animals were estimated to weigh 80-100 g, with a head and body length of 110-140 mm, and a tail length of 140-160 mm.The encounter rate was 0.4 animals/h from 91 h of total survey time. These dwarf galagos have cinnamon-brown on the dorsum and flanks, with an orange-brown tinge on the shoulders and thighs. They have a pale nose stripe, and the end of the muzzle appears 'turned up' (reminiscent of a Demidoff's dwarf galago Galagoides demidoff). The pelage of the tail varies from greyish-brown to cinnamon-brown, but is generally the same colour as the dorsum apart from a darkening towards the tip. The tail is slightly "bushier" over the distal one-third. Although traps were set for a total of 87 trap nights, no dwarf galagos were captured.The dwarf galagos called briefly at dusk, and then rarely during the night and at dawn. Eight types of calls were tape-recorded (table 2). The advertisement calls were almost all heard around dusk but the alarm calls could be heard throughout the night.Table 2. Vocalizations tape-recorded of the Taita mountain dwarf galago Galagoides sp. The alarm calls are highly varied making it impossible to be precise about the numbers of calls.CallNumber recordedContextYap sequences on their own (table 3)1AlarmYaps and bouts of rapid descending yaps1AlarmYaps and descending screeches (table 3)4AlarmGrunt screeches and yaps (table 3)1AlarmIncremental calls (figure 3)3Vocal advertisementDouble unit (figure 1, table 3)5Vocal advertisementBuzzes and screeches (table 3)1AlarmWhistled buzz (table 3)1AlarmDISCUSSIONThe vocalizations and morphology of O. garnettii in the Taita Hills were consistent with other populations in East Africa (Masters, 1991; Honess, 1996; A. Perkin, unpublished data). This species is abundant in the Taita Hills, where it occupies forest edge, secondary vegetation, and wooded farmland habitats. The differences in weight of males and females are consistent with the Kenya coastal population of this species (Harcourt & Nash, 1986).We identify the dwarf galagos of the Taita Hills as a form of Galagoides. From what we saw and heard, this animal is most similar to G. orinus. This represents a new primate species record for the Taita Hills and Kenya. We do not believe that the dwarf galagos of the Taita Hills were the same as the specimens taken by Loveridge.The vocal repertoire of the "Taita mountain dwarf galago" is qualitatively different from that of G. senegalensis (Zimrnermann et al., 1988), G. zanzibaricus, G. rondoensis (Honess & Bearder, 1996; Perkin 2000b), G. demidoff, and Thomas's dwarf galago Galagoides thomasi (Wickings et al., 1998; Bearder, 1999; Ambrose & Perkin, 2000). The contact/advertisement "double unit" call and the two alarm calls ("yaps and descending screeches", and "whistled buzz") of the Taita mountain dwarf galago resemble those of G. orinus, but the Taita animals were not heard to give two calls known for G. orinus at other sites in the Eastern Arc Mountains ("grunt shriek" and "high pitch squeak") (table3). In addition, the "double unit call" (figure 1) is different in structure and quality to the "double unit" call of G. orinus in the East and West Usambara, Uluguru, Udzungwa and Rubeho Mountains (figure 2). The situation is further confused by the fact that the Taita mountain dwarf galago gives an "incremental" advertisement call (figure 3) not heard from G. orinus elsewhere, and which is similar to the "incremental" call of G. z. cocos (figure 4.) (Courtenay & Bearder, 1988; Bearder et al., 1995; A. Perkin & T. Butynski, unpublished data).Table3. Vocal repertoire of the mountain galago Galagoides orinus in the Uluguru, Udzungwa, Rubeho, and Usambara Mountains, Tanzania. Names of calls as assigned by Honess (1996). The asterisk (*) denotes calls heard in the Taita Hills, Kenya.Name of callDescription* "Double unit call"Comprised of two soft units. First unit made at a higher pitch than second, and uttered in a series up to six times at a regular tempo to form a phrase. This probably the call Honess (1996) describes as the "repetitive call", but the call heard in the Ulugurus differs due to altering pitch levels. This seems to be the contact/advertisement/territorial-call. Counter-calling often heard; sometimes between three animals (particularly at dawn and dusk).* "Yaps and descending screeches"Series of phrased "screeches" linked by "yaps" (very short high-pitched units). "Yaps" may be uttered for more than 3 minutes before breaking into "screeches", which only last 5-10 seconds. The entire calling bout may last 5 minutes to over 60 minutes. Used in intense alarm situations (e.g. when a potential predator is spotted). Given at any time during the night.* "Whistled buzz"Strange, descending "buzz" lasting 1-2 seconds. Sometimes uttered in a descending series or as a start to a series of "yaps" and/or "shrieks" depending on the degree of alarm. 'Buzzes' uttered alone indicate mild alarm, surprise or curiosity, possibly when something unusual is present (e.g. torchlight)."Grunt shriek"Quiet, low pitch, low volume call made by swallowing air rapidly while simultaneously uttering screeches. This call usually implies extreme alarm (due to the considerable physical effort used to make this call).* "Yap"Very short high pitched call. Usually uttered in series and in conjunction with other calls like "screeches" and "buzzes". Made in a variety of contexts from mild alarm to extreme alarm. The rapidity, frequency and amplitude usually increases with the degree of alarm."High pitch squeak"Very high pitch call uttered singly, or in series of 2-3 units, or breaking into "screeches". Often given high in the canopy. Unclear in what behavioural context this call is made.The Taita mountain dwarf galago is considerably smaller (estimated to be 80-100 g) than G. zanzibaricus (104-203 g) or G. senegalensis (112-300 g) (Olson & Nash, in press), indicating that it belongs to the smallest (dwarf) group of galagos, which includes G. orinus (45-95 g) (Honess & Bearder, 1996; Kingdon, 1997; Perkin, 2000a,b). The characteristically reddish-brown bushy tail of G. orinus was not observed in the Taita animals. Instead, the tail is greyish-brown to cinnamon-brown with a dark tip, like that of G. zanzibaricus.Figure 1. Sonogram of the "double unit" advertisement call of the Taita mountain dwarf galago Galagoides sp. This call resembles the "double unit" call of Galagoides orinus in other Eastern Arc Mountains (figure 2). The two units are given close together, but the first unit is stronger in amplitude and longer than the second unit. The "fundamental frequency" is that part of the call with the lowest frequency and greatest amplitude and, therefore, is the farthest travelling element of the call. The fundamental frequency of the "double unit" of the Taita mountain dwarf galago is 2.67 kHz.Figure 2. Sonogram of the "double unit" advertisement call of the mountain galago Galagoides orinus in the Uluguru Mountains, Tanzania. Each part of the double unit is equal in amplitude and frequency, and there is sometimes a single unit at the beginning and at the end of the call (A. Perkin, unpublished data). The fundamental frequency is 1.56 kHz.Figure 3. Sonogram of the "incremental" advertisement call of the Taita mountain dwarf galago Galagoides sp. This call resembles the "incremental" call of the Zanzibar galago Galagoides zanzibaricus cocos on the Kenya coast (figure 4). Units are uttered together and the number of units increases "incrementally", as does the amplitude and frequency. The "extra" single unit at the end is not uttered in a typical "incremental" call. There is no discemable fundamental frequency in this call and the units have a wide frequency range (2-11 kHz).Figure 4. Sonogram of the "incremental" call of the Zanzibar galago Galagoides zanzibaricus cocos from Diani Forest on the coast of southern Kenya. This call has four strong bursts of "chirrups"' followed by shorter phrases of units increasing incrementally (S. Bearder, unpublished data). There is no discemable fundamental frequency in this call and the units utilise a wide frequency range (1.5-11kHz).The elevation of the forests of the Taita Hills where the Taita mountain dwarf galago occurs (1,600-1,900 m) is similar to the elevation of the other forests in the Eastern Arc Mountains where G. orinus occurs (650-2,400 m). G. zanzibaricus is not known to occur above 1,000 m (Butynski et al., 1998, T. Butynski, C. Ehardt & A. Perkin unpublished data). The habitat and forest strata use by the Taita mountain dwarf galago are also similar to those used by G. orinus (Honess, 1996; Perkin, 2000a). The frequency of calling was much lower in the Taita Hills (0.4 animals/h) than for G. orinus at other sites. For example, 2.7 and 5.4 calling animals/h were heard for two sites in the Uluguru Mountains (Perkin, 2000a), and similar high rates were noted for more than a dozen sites in the Udzungwa Mountains (T. Butynski & C. Ehardt, unpublished data).Calling rates and encounter rates in the Taita Hills are also much lower than those of G. z. cocos on the coast of Kenya where encounter rates are as high as 12/h (A. Perkin & T. Butynski, unpublished data). In the coastal forests of Kenya, densities of G. z. cocos were estimated to be 170-180 individuals/km⟨sup⟩2⟨/sup⟩ (Harcourt & Nash, 1986). The apparently low densities of the Taita mountain dwarf galago may be due to the small size of the forest fragment, or to animals that are perhaps particularly shy and cryptic. The surveys were conducted during July, which may coincide with low levels of calling (possibly related to territoriality and breeding).Similarities in size, morphology, habitat, elevation, and vocal repertoire with G. orinus support the provisional identity of this dwarf galago as G. orinus. However, some differences in vocalizations, colour, and morphology indicate the possibility that the Taita mountain dwarf galago represents a new taxon (sub-species or species) of Galagoides closely related to either G. orinus or G. zanzibaricus, or both.The specimens of the small galagos collected by Loveridge in 1934, were all identified as G. senegalensis braccatus by Loveridge, as well as by Allen and Lawrence (1936), and Lawrence and Washburn (1936). Based on the information available to us, we agree, and concluded that Taita mountain dwarf galago was not among the specimens obtained by Loveridge. As far as we are aware, the Taita mountain dwarf galago has never been collected or otherwise previously identified.Preliminary analyses of vocalization and morphology data for G. orinus in other long-isolated Eastern Arc Mountains forests, such as the Ulugurus (Perkin, 2000a), the Udzungwas (Butynski et al., 1998; Perkin, 2001), and the East Usambaras (Honess, 1996; Perkin 2000a), show interpopulation differences. The significance of this variation is not yet understood. The Taita mountain dwarf galago might be different to other dwarf galagos due to the long isolation of the Taita Hills forests, both from other forest refugia within the Eastern Arc Mountains, and from the East Africa coastal forests. Indeed, a pattern of endemism in the Taita Hills has already been demonstrated both for plants and animals (Beentje, 1988; Lovett & Wasser, 1993; Collar et al., 1994; Brookes et al, 1998a,b; Bytebier, 2001). Molecular data, together with additional data on the morphology, vocalizations, behaviour, and ecology of the Taita mountain dwarf galago, are necessary to confirm its taxonomic status, and to evaluate its interpopulation variability and biogeographical affinities.ACKNOWLEDGMENTSWe thank Julia Munch and the staff of the Taita Hills Biodiversity Project for their field assistance, and Primate Conservation Incorporated and Zoo Atlanta for financial support.The Taita Hills Biodiversity Project was supported by a grant from the Flemish Interuniversity Council to W. Verheyen and E. Mathyssen, University of Antwerp, Belgium. Thanks also to Nike Doggart and Kathryn Doody for comments on this manuscript, and to Judy Chupasko and Mark Omura for providing information on specimens of galagos in the collection-of the Museum of Comparative Zoology, Harvard University.REFERENCESAllen, G. M. & A. Loveridge (1936). Reports on the scientific results of an expedition to the south-western highlands of Tanganyika Territory. II. Mammals. Bulletin of the Museum of Comparative Zoology Harvard Coll. 75: 47-140.Ambrose, L. & A.W. Perkin (2000). A survey of nocturnal prosimians at Moca on Bioko Island, Equatorial Guinea. African Primates 4: 4-10.Anderson, M. (1998). Comparative morphology and speciation in galagos. Folia Primatologica 69: 325-331.Anderson, M.J. (1999). The use of hand morphology in the taxonomy of galagos. Primates 40: 469-478.Bearder, S.K. & D.A. Doyle (1974). Ecology of bushbabies Galago senegalensis and Galago crassicaudatus, with some notes on their behaviour in the field. In R.D. Martin, D.A.Doyle, & AC. Walker (eds.), Prosimian Biology. Duckworth, London. Pp. 109-130.Bearder, S. K., P.E. Honess & L. Ambrose (1995). Species diversity among galagos, with special reference to mate recognition: In L. Alterman, M.K. Izaard. & G.A. Doyle (eds). Creatures of the Dark: The Nocturnal Prosimians. Plenum Press, New York. Pp. 331-352.Bearder, S.K. (1999). Physical and social diversity among nocturnal primates: a new view based on long term research. Primates 40: 267-282.Beentje, H.J. (1988). An ecological and floristic study of the forests on the Taita Hills, Kenya. Utafiti 1: 23-66.Brookes, T., L. Lens, J. Barnes & J.K. Kihuria (1998a). The conservation status of the forest birds of the Taita Hills, Kenya. Bird Conservation International 8: 119-139.Brookes, T., L. Lens, M. De Meyer, E. Waiayaki & C. Wilder (1998b). Avian biogeography of the Taita Hills, Kenya. Journal of East African Natural History 87: 189-194.Butynski, T.M., C.L. Ehardt & T.L. Struhsaker (1998). Notes on two dwarf galagos Galagoides udzungwensis and Galagoides orinus) in the Udzungwa Mountains, Tanzania. Primate Conservation 18: 69-75.Bytebier, B. (2001). Taita Hills Biodiversity Project Report. National Museums of Kenya, Nairobi. http://bio-www.uia.ac.be/bio/deco/THBP_final_report.pdf.Charles-Dominique, P. (1977). Ecology and Behaviour of Nocturnal Primates. Duckworth, London.Chege, J. & B. Bytebier (submitted). Vegetation structure and composition of four small Taita Hills forest fragments. Journal of East African Natural History.Collar, N. J., A.J. Stattersfield & M.J. Crosby (1994). Birds to Watch 2. The World List of Threatened Birds. BirdLife International, Cambridge.Courtenay, D.O. & S.K. Bearder (1988). The taxonomic status and distribution of bushbabies in Malawi with emphasis on the significance of vocalizations. International Journal of Primatology 10: 17-34.Dixson, A.F. (1987) Observations on the evolution of genitalia and copulatory behaviour in male primates. Journal of Zoology, 213: 423-443.Dixson, A.F. (1989). Sexual selection, genital morphology, and copulatory behavior in male galagos. International Journal of Primatology 10: 47-55.Dorst, J & P. Dandelot (1990). A Field Guide to the Larger Mammals of Africa. Collins, London.Groves, C.P. (2001). Primate Taxonomy. Smithsonian Institution Press, Washington D.C.Grubb, P, T.M. Butynski, J.F. Oates, S.K. Bearder, T.R. Disotell, C.P. Groves, & T.T. Struhsaker (In press). An assessment of the diversity of African primates. International Journal of Primatology.Harcourt, C.S. & L.T. Nash (1986). Species differences in substrate use and diet between sympatric galagos in two Kenyan coastal forests. Primates 27: 41-52.Hill, W.C.O. (1953). Primates, Comparative Anatomy and Taxonomy, Vol. 1. Strepsirhrini. Edinburgh University Press.Honess, P.E. (1996). Speciation Among Galagos (Primates, Galagoidae) in Tanzanian Forests. Ph.D. thesis, Oxford Brookes University, Oxford.Honess, P.E. & S.K. Bearder (1996). Descriptions of the dwarf galago species of Tanzania. African Primates. 2 75-79.ICBP (1992) Putting Biodiversity on the Map: Priority Areas for Global Conservation. International Council for Protection of Birds, Cambridge.Jenkins, P.D. (1987). Catalogue of Primates in the British Museum (Natural History), Part IV: Suborder Strepsirhini. British Museum of Natural History, London.Kingdon, J. (1997). The Kingdon Field Guide to African Mammals. Academic Press, London.Lawrence, B., & S.L. Washburn (1936). A new eastern race of Galago demidovii. Occasional Papers of the Boston Society of Natural History 8: 255-266.Lovett, J.C. & S.K. Wasser (eds.) (1993). Biogeography and Ecology of the Rain Forests of Eastern Africa. Cambridge University Press, Cambridge.Masters, J.C. (1988). Speciation in the greater galagos (Prosimii: Galaginae): A review and synthesis. Biological Journal of the Linnean Society 34: 149-174.Masters, J.C. (1991). Loud calls of Galago crassicaudatus and G. garnetti and their relation to habitat structure. Primates 32: 153-157.Masters, J.C. (1995). Speciation in lesser galagos. International Conference on the biology and Conservation of Prosimians. North of England Zoological Society, Chester Zoo, 13-16 September 1995.Mittermeier, R.A., N. Myers, J.B. Thomsen, G.A.B. da Fonseca & S. Olivieri (1998). Global biodiversity hotspots and major wilderness areas. Conservation Biology 12: 516-520.Myers, N., R.A. Mittermeier, C.G. Mittermeier, G.A.B. da Fonseca & J. Kent (2000). Biodiversity hotspots for conservation. Nature 403: 853-858.Nash, L.T., S.K. Bearder & T. Olson (1989). Synopsis of galago species characteristics. International Journal of Primatology 10: 57-80.Olson, T.R. 1979. Studies on Aspects of the Morphology and Systematics of the Genus Otolemur. PhD thesis, University of London, U.K.Olson, T.R. & L.T. Nash (In press). Galago (Galagonidae) taxa body measurements and museum collections data. African Primates 5.Perkin, A.W. (2000a). The Taxonomic Status of Bushbabies (Galagos) in the Uluguru Mountains. Technical report for the Wildlife Conservation Society of Tanzania, Dar es Salaam. www.africanconservation.com/uluguruPerkin, A.W. (2000b). A Field Study on the Conservation Status and Species Diversity of Galagos in Zareninge Forest, Coast Region, Tanzania. Unpublished report to World Wildlife Fund, Tanzania.Perkin, A.W. (2001). A field study on the conservation status and species diversity of galagos in the West Kilombero scarp forest reserve. In: Frontier. West Kilombero Scarp Forest Reserve. Report for MEMA, Iringa, Tanzania. pp. 149-159.Thomas, M.R.O. & R.C. Wroughton (1907). The Rudd exploration of South Africa - 7. List of mammals obtained by Mr. Grant at Conguno, Inhambane. Proceedings of the Zoological Society of London 1907: 285-299.Wickings, E.J., L. Ambrose & S.K. Bearder (1998). Sympatric populations of Galagoides demidoff and G. thomasi in Haut Ogooue Region of Gabon. Folia Primatologica 69: 49 200-202.Wilder, C, T. Brooks & L. Lens (1998). Vegetation structure and composition of the Taita Hills forests. Journal of East African Natural History 87: 181-187.Zimmermann, E. (1990). Differentiation of vocalisations in bushbabies (Galaginae, Prosimiae, Primates) and the significance for assessing phylogenetic relationships. Zeitschrift fuer Zoologische Systematik und Evolutionsforschung 28: 217-239.Zimmermann, E., S.K. Bearder; G.A. Doyle & A.B. Andersson (1988). Variations in vocal patterns of lesser bushbabies (Galago senegalensis and Galago moholi) and their implications for taxonomic relationships. Folia Primatologica 51: 87-105.