Animal Diversity Web

Ge­o­graphic Range

Galago al­leni lives in the rain­for­est of west-cen­tral Africa. It has been found nearly as far north as south­ern Nige­ria, west to the delta of the Niger river, as far east as the south­west­ern cor­ner of the Cen­tral African Re­pub­lic, and south to south­ern Congo. (Flan­nery, 2001; Nowak, 1991; Wolfheim, 1983)

• Biogeographic Regions
• ethiopian
  • native

Habi­tat

Galago al­leni is most fre­quently found in the un­der­story of ma­ture pri­mary wet forests. This species is rarely pre­sent in sec­ondary growth forests. (Muller and Grz­imek, 1990; Wolfheim, 1983)

• Habitat Regions
• tropical
• terrestrial

• Terrestrial Biomes
• forest
• rainforest

Phys­i­cal De­scrip­tion

Galago al­leni has thick fur that can range from grey to brown in color with a rust tint on the limbs. The ven­tral fur tends to be lighter rang­ing from grey to a yel­lowed white. This species has dis­tinct dark patches of fur around its eyes. The tail is long and bushy. Head and body length ranges from 155 to 240 mm and mass from 200 to 445 grams.

Like other mem­bers of the genus, G. al­leni has un­usu­ally large eyes, which help to adapt this species to a noc­tur­nal life style. These large eyes have a re­flec­tive retina, the tape­tum, which fa­cil­i­tates light de­tec­tion. In­ter­est­ingly, these an­i­mals are color-blind, with only rods in the retina and no true mac­ula.

Like many of their rel­a­tives, Allen's bush ba­bies have flex­i­ble, naked ears that can moved back­ward, and be bent down to the base. The nose has a spe­cial­ized leather-like cov­er­ing with slits. Galago al­leni has the char­ac­ter­is­tic tooth­comb com­mon in gala­gos, made up of the four in­cisors and two ca­nines. They are known for their strong hindlimbs and leap­ing abil­ity. (Muller and Grz­imek, 1990; Napier, 1967; Nowak, 1991)

• Other Physical Features
• endothermic
• bilateral symmetry

• Sexual Dimorphism
• sexes alike

• Range mass

  200 to 445 g

  7.05 to 15.68 oz

• Range length

  155 to 240 mm

  6.10 to 9.45 in

Re­pro­duc­tion

Males seek to con­trol home ranges that over­lap those of sev­eral fe­males. In­tense com­pe­ti­tion be­tween males for ac­cess to fe­male home ranges is ob­served. Male dom­i­nance seems to be cor­re­lated with body mass, with larger males being the most dom­i­nant. (Muller and Grz­imek, 1990; Nowak, 1991)

• Mating System
• polygynous

Fe­males have one baby at a time. Births occur year round in some parts of the range and in sea­sonal peaks in other parts of the range. In Gabon, where births occur year-round, there is an in­crease of births from Jan­u­ary to April. Peaks in births occur dur­ing times of the year when fruits and in­sects are most abun­dant. Ges­ta­tion is un­usu­ally long (around 133 days). Birth weights are low (5 to 10 grams) when com­pared to other an­i­mals of the same size. The fe­male sep­a­rates her­self from the group for two weeks when giv­ing birth. Wean­ing oc­curs at about 6 weeks of age. Young Allen's bush ba­bies be­come sex­u­ally ma­ture at around 8 to 10 months of age. (Muller and Grz­imek, 1990; Nowak, 1991; Rowe, 1996)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• year-round breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• fertilization
• viviparous

• Breeding interval

  Females typically have one pregnancy per year.

• Breeding season

  Breeding occurs seasonally and year-round in different parts of the range.

• Average number of offspring

  1

• Average number of offspring

  1.3

  AnAge

• Average gestation period

  133 days

• Average gestation period

  133 days

  AnAge

• Average weaning age

  6 weeks

• Range age at sexual or reproductive maturity (female)

  8 to 10 months

• Range age at sexual or reproductive maturity (male)

  8 to 10 months

Galago al­leni build nests for their young and some­times share the care of young with other fe­males with in­fants. Fe­males carry their young in their mouths. When they leave the nest to for­age at night, they carry their de­pen­dent off­spring to a hid­ing place. The fe­male leaves her young in hid­ing while she searches for food. Fe­males nurse their young for about six weeks.

The role of males in parental care ap­pears to be in­di­rect. Be­cause males ag­gres­sively main­tain their ranges, which over­lap those of sev­eral fe­males, it can be ar­gued that they help to de­fend the young from in­vad­ing males. (Nowak, 1991; Rowe, 1996)

• Parental Investment
• altricial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • male
    • female
• pre-independence
  • protecting
    • male
    • female

Lifes­pan/Longevity

In cap­tiv­ity G. al­leni has been found to live about 12 years. This species has been known to live 8 years in the wild. (Nowak, 1991; Rowe, 1996)

• Range lifespan
  Status: wild

  8 (high) years

• Range lifespan
  Status: captivity

  12 (high) years

• Average lifespan
  Status: captivity

  12.0 years

  Max Planck Institute for Demographic Research

Be­hav­ior

Galago al­leni is noc­tur­nal. Males are pri­mar­ily soli­tary and are ag­gres­sive to­wards other males. Fe­males often stay in small groups with in­fants. Males and fe­males may share nest sites dur­ing the day. In­di­vid­u­als sleep in nests built in tree hol­lows in groups of about 1 to 4. The males live alone or in small groups of 2 or 3 until the op­por­tu­nity to be a dom­i­nant male arises. Dom­i­nant males cover a large ter­ri­tory. They tend to be quite ter­ri­to­r­ial, and there is in­tense com­pe­ti­tion for prox­im­ity to fe­male home ranges. These more dom­i­nant males may go be­tween many fe­male groups. Male ag­gres­sion is sig­naled by an up­right, bipedal pos­ture, an open mouth, and a hiss­ing vo­cal­iza­tion.

Allen's bush ba­bies mark their ter­ri­tory by "urine wip­ing." They uri­nate on the soles of their feet and then march around their ter­ri­tory until the scent is well en­trenched. This urine mark­ing be­hav­ior is com­mon in most gala­gos. On av­er­age there are 15 G. al­leni per square mile.

Galago al­leni par­tic­i­pates in so­cial groom­ing, using the tooth­comb and spe­cial­ized groom­ing sec­ond toe. Groom­ing is also a courtship be­hav­ior. The tooth­comb cleans soiled areas of the fur and a sec­ond tongue in the mouth of the bush baby cleans the tooth­comb. This is a be­hav­ior that is com­mon in gala­gos. (Bearder, et al., 1986; Flan­nery, 2001; Muller and Grz­imek, 1990; Napier, 1967; Nowak, 1991; Rowe, 1996)

• Key Behaviors
• arboreal
• nocturnal
• motile
• sedentary
• territorial
• social
• dominance hierarchies

Home Range

Fe­males have a home range of 8 to 16 ha, while males have a larger range of 30 to 50 ha. (Muller and Grz­imek, 1990; Napier, 1967; Nowak, 1991)

Com­mu­ni­ca­tion and Per­cep­tion

Allen's bush ba­bies com­mu­ni­cate through 3 cat­e­gories of sound--so­cial, ag­gres­sion, and de­fense. So­cial com­mu­ni­ca­tion tends to be in the form of click­ing noises from young to mother, sound­ing some­thing like "tsic." A ma­ter­nal call to the group sounds some­thing like a soft croak. More pow­er­ful noises are for large groups to as­sem­ble. If an alarm call is heard, it can cause G. al­leni to gather and mob a preda­tor such as a cat. The ag­gres­sive call sounds like "quee, quee, quee."

There is also ol­fac­tory com­mu­ni­ca­tion through urine which marks the ter­ri­tory of G. al­leni. This urine ter­ri­tory mark­ing was found to in­crease by about four times when the ter­ri­tory over­lapped with an­other galago. Galago al­leni is very ter­ri­to­r­ial and ag­gres­sion is fre­quently seen be­tween males. The ag­gres­sive be­hav­ior is com­mu­ni­cated through an up­right pos­ture, on the hind legs, and a vocal hiss­ing sound. Courtship is com­mu­ni­cated by mu­tual groom­ing and chas­ing.

Galago al­leni has the abil­ity to make many fa­cial ex­pres­sions, which can com­mu­ni­cate a great deal. Fa­cial ex­pres­sions can be de­fen­sive, threat­en­ing, or pro­tec­tive, and are also as­so­ci­ated with ma­ter­nal clicks.

Gala­gos use tac­tile com­mu­ni­ca­tion. Upon first en­counter with a con­spe­cific, they may sniff each other nose to nose. Then they will touch nose to face. So­cial groom­ing is their most im­por­tant form of touch, and this helps them bond with one an­other. (Flan­nery, 2001; Napier, 1967; Nowak, 1991; Rowe, 1996)

Galago al­leni has an ex­cep­tion­ally well-de­vel­oped sense of vi­sion (though lack­ing color vi­sion) at night. They also have acute hear­ing, sense of smell, and use tac­tile cues to sense their en­vi­ron­ment. (Napier, 1967; Nowak, 1991)

• Communication Channels
• visual
• tactile
• acoustic
• chemical

• Other Communication Modes
• scent marks

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

Allen's bush ba­bies are pri­mar­ily fru­gi­vores, es­pe­cially eat­ing fallen fruit. Fruit makes up an es­ti­mated three quar­ters (75%) of their diet. They also eat in­sects and oc­ca­sion­ally small mam­mals, which may func­tion as pro­tein sup­ple­ments. (Muller and Grz­imek, 1990; Nowak, 1991; Rowe, 1996)

• Primary Diet
• herbivore
  • frugivore

• Animal Foods
• mammals
• amphibians
• eggs
• insects
• terrestrial non-insect arthropods

• Plant Foods
• fruit

Pre­da­tion

When feel­ing threat­ened, G. al­leni has the abil­ity to move more quickly by run­ning on its hind legs. When it spots a preda­tor it quickly jumps great dis­tances from branch to branch. Galago al­leni uses alarm calls to alert con­specifics of the dan­ger.

Lit­tle is known about their preda­tors, al­though ar­bo­real and volant preda­tors, such as cats and owls, are likely to be their main threats. Hu­mans pose the great­est known threat through habi­tat de­struc­tion. (Muller and Grz­imek, 1990; Napier, 1967; Nowak, 1991; Wolfheim, 1983)

• Known Predators

  • humans (Homo sapiens)

Ecosys­tem Roles

G. al­leni is an im­por­tant preda­tor of in­sects and pos­si­bly dis­perses the seeds of the fruits that they eat.

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

There is no sig­nif­i­cant de­mand for G. al­leni, and it is not rou­tinely hunted or cap­tured. It is also rare that Allen's bush ba­bies are ex­ported for the pet trade or re­search. (Napier, 1967)

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

There do not seem to be any neg­a­tive im­pacts of G. al­leni on hu­mans.

Con­ser­va­tion Sta­tus

Galago al­leni is on the IUCN Red List as a lower risk threat­ened species, and is on the CITES Ap­pen­dix II list. The great­est threat to Allen's bush ba­bies is human im­pact on their habi­tat. Ex­pand­ing human pop­u­la­tions, and a civil war in Nige­ria, have dras­ti­cally de­creased the ex­tent of avail­able habi­tat. Be­cause G. al­leni so strongly prefers pri­mary forests to sec­ondary forests this de­struc­tion of their habi­tat is a major con­cern for this species.

Even though human hunt­ing does not ap­pear to be a sig­nif­i­cant prob­lem for the species, laws pro­tect G. al­leni from being hunted or cap­tured with­out au­tho­riza­tion. A re­serve also ex­ists in Cameroon where G. al­leni has been re­ported, but many more re­serves are needed. (Nowak, 1991; Rowe, 1996; Wolfheim, 1983)

• IUCN Red List

  Least Concern
  More information

• IUCN Red List

  Least Concern
  More information

• US Federal List

  No special status

• CITES

  Appendix II

Other Com­ments

Bush ba­bies get their com­mon name from their alarm call, which sounds like a baby lost in the bushes. (Napier, 1967)

Con­trib­u­tors

Nancy Shef­ferly (ed­i­tor), An­i­mal Di­ver­sity Web.

Anna Den­gel (au­thor), An­drews Uni­ver­sity, Tom Good­win (ed­i­tor), An­drews Uni­ver­sity.

Ref­er­ences

In­ter­na­tional Union for Con­ser­va­tion of Na­ture and Nat­ural Re­sources. "Galago al­leni" (On-line ). IUCN Red List of Threa­t­end Species. Ac­cessed 1/27/03 at http://​www.​redlist.​org/​search/​details.​php?​species=8785.

Bearder, S. K., B. Smuts, D. Ch­eney, R. M. Sey­farth, R. W. Wrang­ham, T. T. Struh­saker. 1986. Lorises, Bush­ba­bies, and Tar­siers: Di­verse So­ci­eties in Soli­tary For­agers. Pp. 11-24 in Pri­mate So­ci­eties. Chicago: The Uni­veristy of Chicago Press.

Flan­nery, S. 2001. "Galago al­leni" (On-line ). Pri­mate Info Net. Ac­cessed 10/15/02 at http://www. primate.​wisc.​edu/​pin/​factsheets/​galago_​alleni.​html.

Muller, E., B. Grz­imek. 1990. Lorises and Gala­gos. Pp. 77-95 in En­cy­clo­pe­dia of Mam­mals, Vol. 2. New York: Mc­Graw Pub­lish­ing Co..

Napier, J. 1967. A Hand­book of Liv­ing Pri­mates. Lon­don: Aca­d­e­mic Press Inc..

Nowak, R. 1991. Gala­gos, or Bush Ba­bies. Pp. 408-409 in Walker's Mam­mals of the World, Vol. 1, 5th Edi­tion. Bal­ti­more: Johns Hop­kins Uni­ver­sity Press.

Rowe, N. 1996. The Pic­to­r­ial Guide to Liv­ing Pri­mates. East Hamp­ton: Pogo­nias Press.

Wolfheim, J. H. 1983. Pri­mates of the World. Seat­tle: Uni­ver­sity of Wash­ing­ton Press.