Geographic Range
The range of Thomas’s bushbabies extends from Cote d'Ivoire through Cameroon, Angola,
and Congo-Zaire to Uganda, Tanzania, and Zambia, and possibly northern Kenya around
Mount Marsabit. They may occur in several other African countries but due to recent
taxonomic changes this has yet to be clarified.
Habitat
Thomas’s bushbabies are found in a variety of different habitats, including primary
and secondary forests, marshy areas, gallery forest, savanna, and open woodlands such
as miombo. They inhabit both lowland forests and highland forest and wooded areas
up to 2000 meters.
- Habitat Regions
- tropical
- terrestrial
- Terrestrial Biomes
- savanna or grassland
- forest
- rainforest
- scrub forest
- mountains
- Other Habitat Features
- riparian
Physical Description
Thomas’s bushbabies are brownish-grey with grey underparts, prominent dark eye patches,
narrow faces, and dark rostra. Thomas’s bushbabies resemble Prince Demidoff’s bushbabies
(
Galago demidoff
). Although not typically visible in the field, a distinguishing feature is the genital
morphology of Thomas’s bushbabies, which differs from all other members of the
Galagidae
family. The body length of
Galago thomasi
averages 146 mm, with a range of 123 to 166 mm, tail length averages 261 mm, ranging
from 150 to 233 mm. Thomas’s bushbabies weigh, on average, 99 g, but varies in weight
from 55 to 149 g. Males are larger than females.
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- male larger
Reproduction
Studies of the reproductive behavior of
Galago thomasi
are lacking. In other members of the family
Galagidae
for which data are available, the mating systems consist of polygynous multi-male
groups. Male galagos have a baculum, and there are typically species-specific differences
in penile morphology among the
Galagidae
.
- Mating System
- polygynandrous (promiscuous)
Although data are lacking for
G. thomasi
, other
galagos
, such as
Galago demidoff
, breed year-round. Typically they reproduce between January and April. Information
on the gestation period and the number of offspring born are not available for
Galago thomasi
, however, in
Galago demidoff
females have a gestation period of 111 to 114 days and one young at a time. Offspring
in
G. demidoff
are weaned at around 53 days of age and reach sexual maturity at an age of 8 to 10
months.
- Key Reproductive Features
- iteroparous
- year-round breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- viviparous
There is no information currently on parental investment in G. thomasi and whether or not there are male and female contributions to the care of offspring. In other Galago species females primarily care for the young and generally hide them in a protected spot while they forage. Males may provide some indirect care for young through protecting foraging areas and there is some evidence that males may associate with females and their young on occasion.
- Parental Investment
-
pre-fertilization
- provisioning
-
protecting
- female
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- female
-
provisioning
Lifespan/Longevity
The lifespan of
Galago thomasi
is not reported in the literature. The closely related
Galago demidoff
has been known to live 13 years in the captivity.
Behavior
Thomas’s bushbabies are both nocturnal and arboreal. They spend much of their waking
time foraging solitarily. They inhabit higher levels of the forest, usually above
20 meters. After foraging for the night individuals usually come together in the early
morning hours before dawn. They have been found sleeping together as well. Group dynamics
are considered complex, but groups are highly dispersed during foraging periods. They
have been observed allogrooming when meeting one another and they make many postural
motions with their bodies. Compared to
Galago matschei
,
G. thomasi
uses arboreal quadrupedalism more, although both species make much use of leaping.
Thomas’s bushbabies primarily use small, oblique, mid-canopy branches. In Kibale Forest,
Uganda, Thomas’s bushbabies were reported nesting in the night nest of a common chimpanzee
Pan troglodytes
, despite the fact that chimpanzees regularly prey upon galagos.
- Key Behaviors
- arboreal
- scansorial
- saltatorial
- nocturnal
- motile
- sedentary
- solitary
- territorial
- social
Home Range
Home range size in Thomas’s bushbabies is not known. In another species,
Galago demidoff
, the home range was found to be 0.6 to 1.4 ha.
Communication and Perception
The facial markings of the different species in the family
Galagidae
may help them distinguish one individual from another when they come into contact.
Galago thomasi
individuals use chemical cues extensively. They have a scent gland near the anal
region that is used in scent marking to communicate with conspecifics. They also urinate
on their cupped hands, then spread the urine on their feet, so it is spread when they
walk. This behavior, urine-washing, is more frequent in males than females, and is
carried out in a variety of situations. Thomas’s bushbabies also have species-specific
calls: they have a rolling call that rises to a crescendo and is then repeated several
times. These calls can be used to communicate position to one another as well as to
indicate mood.
Tactile communication takes the form of nose-to-nose sniffing then nose-to-face contact
when conspecifics first encounter each other. They also reciprocally lick each other,
depositing saliva and sometimes urine.
- Other Communication Modes
- scent marks
Food Habits
Like other
galagos
, Thomas’s bushbabies eat a variety of foods, but are primarily insectivorous. They
consume small vertebrates and insects, fruit, tree buds and leaves, as well as tree
gums. They use their large ears to listen for insects and small vertebrates and have
been known to catch insects in mid-air.
- Animal Foods
- reptiles
- insects
- terrestrial non-insect arthropods
- Plant Foods
- seeds, grains, and nuts
- fruit
- sap or other plant fluids
Predation
Because of their small size, Thomas’s bushbabies are likely to be preyed on by nocturnal
predators such as small carnivores and owls. During the daytime, even though they
sleep in small tree hollows or crevices,
galagos
are not always safe from predators. Common chimpanzees
Pan troglodytes
have been observed using a stick as a spear in order to reach a sleeping
Galago demidoff
in its nest and it seems likely they would prey upon
G. thomasi
as well. Arboreal snakes may also be a threat.
- Anti-predator Adaptations
- cryptic
Ecosystem Roles
Thomas’s bushbabies help to disperse seeds of the fruits that they eat. They also
presumably serve as prey for smaller forest carnivores and regulate arthropod communities
through their predation.
Trypanosomes have been found in the blood of Thomas’s bushbabies in Kivu Province,
Democratic Republic of Congo.
- Ecosystem Impact
- disperses seeds
- trypanosomes ( Trypanosomatida )
Economic Importance for Humans: Positive
Thomas’s bushbabies do not play any major economic roles for humans. They may provoke some interest by ecotourists, but they are active at night and rarely observed.
- Positive Impacts
- ecotourism
Economic Importance for Humans: Negative
There are no known negative impacts of Thomas’s bushbabies on humans.
Conservation Status
The IUCN lists
Galago thomasi
as lower risk/least concern. This status is due to their adaptability to different
types of environments rather than reliance on primary and secondary rainforests that
are being destroyed by humans in Africa for agriculture. With education both for the
local people where the animals live and educating the general public on the importance
of natural ecosystems
Galago thomasi
may be able to stay listed as lower risk least concern.
Additional Links
Contributors
Tanya Dewey (editor), Animal Diversity Web.
Jeremy Phan (author), Michigan State University, Pamela Rasmussen (editor, instructor), Michigan State University.
- Ethiopian
-
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- tropical savanna and grassland
-
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
- savanna
-
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
- temperate grassland
-
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- rainforest
-
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
- scrub forest
-
scrub forests develop in areas that experience dry seasons.
- mountains
-
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
- marsh
-
marshes are wetland areas often dominated by grasses and reeds.
- swamp
-
a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.
- riparian
-
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
- endothermic
-
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- polygynandrous
-
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- year-round breeding
-
breeding takes place throughout the year
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- arboreal
-
Referring to an animal that lives in trees; tree-climbing.
- saltatorial
-
specialized for leaping or bounding locomotion; jumps or hops.
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- solitary
-
lives alone
- territorial
-
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
- social
-
associates with others of its species; forms social groups.
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- scent marks
-
communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- cryptic
-
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
- ecotourism
-
humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
- omnivore
-
an animal that mainly eats all kinds of things, including plants and animals
References
Groves, C. 2001. Primate Taxonomy . United States of America: Smithsonian Institution.
Llorente, M., J. Pi, A. Houle. 2003. Association between Galago thomasi and Pan troglodytes schweinfurthii in the Kibale National Park, Uganda. Folia Primatologica , 74(2): 80-84. Accessed February 01, 2009 at http://content.karger.com/ProdukteDB/produkte.asp?Aktion=ShowAbstract&ProduktNr=223842&Ausgabe=229116&ArtikelNr=70001 .
Macdonald, D. 2001. The Encyclopedia of Mammals . London: The Brown Reference Group.
Off, E., D. Gebo. 2005. Galago locomotion in Kibale National Park, Uganda. American Journal of Primatology , 66(2): 189-195. Accessed February 01, 2009 at http://www3.interscience.wiley.com/journal/110521106/abstract .
Perkin, A., S. Bearder. 2004. "Minziro Forest reveals new galago and bat records for Tanzania" (On-line). The Arc Journal. Accessed February 01, 2009 at http://www.tfcg.org/pdf/arc_article4.pdf .
Rowe, N. 1996. The Pictorial Guide to Living Primates . Hong Kong: Pogonias Press.
Van Den Berghe, L., M. Peel. 2007. Trypanosomes of the African lemurs, Perodicticus potto ibeanus and Galago demidovi thomasi. Journal of Eukaryotic Microbiology , 10(2): 133-135. Accessed February 01, 2009 at http://www3.interscience.wiley.com/journal/119743427/abstract .
1997. Predation on Mammals by the Chimpanzee. Primates , 38(2): 193-214. Accessed September 04, 2008 at http://www.springerlink.com.proxy2.cl.msu.edu:2047/content/547k647u01073811/fulltext.pdf .
2008. "The IUCN Red List of Threatened Species" (On-line). Galagoides thomasi. Accessed February 01, 2009 at http://www.iucnredlist.org/details/40653 .
2007. "Thomas's Galago (Galago thomasi)" (On-line). Accessed February 01, 2009 at http://www.theprimata.com/galago_thomasi.html .