The actual time spent feeding, though, is correlated with the amount of processing time required by the type of food being consumed. The use of tools to obtain some foods has been documented across all chimpanzee populations.
Sticks, rocks, grass, and leaves are all commonly used materials that are modified into tools and used to acquire and eat honey, termites, ants, nuts, and water. For example, to extract honey from the hives of stingless bees, chimpanzees use short sticks stripped of their leaves, twigs, and bark to most effectively scoop it out of the hive.
On the other hand, to extract honey from the hives of aggressive African honeybees, chimpanzees use significantly longer and thinner sticks to avoid the painful stings of these bees Stanford et al. This practice requires some amount of skill, and infant and juvenile chimpanzees must practice a great deal before mastering the technique necessary to extract the ants still clinging to the thin, flexible tools. Often these items are not found together or near a source of nuts, so nut-cracking chimpanzees must exhibit forethought to gather the appropriate accoutrements to eat these important high-protein, high-fat foods.
Chimpanzees also use leaves as sponges or spoons to drink water. Selectively choosing the type of leaf to use, chimpanzees crumple these leaves in their mouths and then submerge them in water; the crumpled leaves act like a sponge and they suck the water out of them and repeat the process Sugiyama This behavior is especially prevalent where water is scarce at certain times of year and it is so deep in tree holes that chimpanzees cannot easily access it directly with their mouths.
Chimpanzees have excellent mental maps of their home ranges and use these to locate food resources repeatedly. Their attention may be directed to a new food source by a noisy group of animals, such as birds or other primates, or they may be led to a new fruit tree or termite mound by a foraging companion that has been there before Goodall Lions are also capable of killing chimpanzees, and predation by lions has been observed at Mahale Mountains National Park in Tanzania, but there are scant observations of lion predation at other sites where they are sympatric with chimpanzees Tsukahara Written by Kristina Cawthon Lang.
Reviewed by Elaine Videan. Cite this page as: Cawthon Lang KA. Accessed July Primate behavioral ecologists have long debated the costs and benefits of group living, but some of the factors that affect chimpanzee social structure include decreased likelihood of predation, resource defense and feeding efficiency, and higher copulatory success because of access to mates Sakura ; Boesch Chimpanzees live in a fission-fusion social group consisting of a large community that includes all individuals that regularly associate with one another up to a few hundred individuals and smaller, temporary subgroups, or parties.
These subgroups are unpredictable and can be highly fluid, changing members quickly or lasting a few days before rejoining the community Goodall ; Chapman et al.
Party size greatly increases when food availability increases, though, and at Kibale, average party size is 10 but ranges from one to 47 individuals during periods of highest food availability Mitani et al. Party size also increases when the estrous females are present Matsumoto-Oda et al. Party composition is variable, including unisexual and bisexual parties of adolescents or adults, parties of adult females and infants, lone adult females and their offspring, and mixed age and sex parties Boesch At Bossou, though, where the adult sex ratio is skewed, the high number of females relative to males means the most common party composition there is mother-infant Boesch Males remain in their natal communities while females, in general, emigrate at adolescence, between nine and 14 years old Nishida et al.
The complete transition between groups may take up to two years, though, and is characterized by vacillating between their natal group and new community Goodall ; Hasegawa ; Pusey This may be attributed to the smaller population size and isolated conditions at Gombe and Bossou; with fewer options, it is more beneficial to remain in their own group and take behavioral precautions to avoid inbreeding Goodall ; Gagneux et al.
For female chimpanzees that do emigrate, though, they are not likely to be related to other adult females in their new community and the dominance hierarchy is linked to age with younger immigrant females ranking the lowest and the status of their offspring Nishida Females become very sociable during estrus , though, and are seen mostly in bisexual parties Pepper et al.
Given the female-biased dispersal pattern, male chimpanzees in a community are more likely to be related to one another than females are to each other, but matrilineal kinship does not always strongly influence patterns of male chimpanzee social behavior.
Research at Gombe, on the other hand, has consistently emphasized kinship as the most important underlying factor of the strong social bonds Goodall Some examples of inter-community interactions include hostile attacks by groups of males and cooperative boundary patrol parties. Hunting is cooperative in the sense that multiple males are involved in cornering and capturing prey, though there is debate among researchers if this is true cooperation Videan pers.
Hunting success increases with group size, and chimpanzees are more successful where the canopy is broken and open. The influence on red colobus Procolobus badius populations because of high success rates of chimpanzee hunters should not be ignored. Chimpanzees are contributing to population declines of red colobus monkeys in multiple sites across Africa, especially at Gombe Struhsaker Males reach adolescence between nine and 15 years of age and are capable of reproduction at 16 years or older.
First estrus is seen in females at 10 years of age and is characterized by anogenital swelling. Menarche occurs a few months after the first swelling and continues on a cycle of about 36 days Goodall There is a period of adolescent infertility in female chimpanzees that usually coincides with permanent emigration from their natal groups Goodall ; Nishida et al.
Once established in their new communities, young females cease cycling for two to four years but continue to attract adult males and mate promiscuously. The lag time between menarche and first parturition may have adaptive significance for emigrating females. Infanticide has been documented at Gombe, Mahale, and Kibale study sites and is often attributed to sexual selection theory ; males kill infants unlikely to be their own, infanticide shortens interbirth intervals by inducing cycling in females that lose infants, and infanticidal males thus increase their chances of siring offspring.
Infanticidal behavior by females has also been observed, though there is some question as to whether these were isolated incidences of pathological behavior, or if it could be related to dominance rank in females Goodall ; Pusey et al. The number of estrous females is positively related to food abundance; because of the energetic requirements of ovulation and mating, female chimpanzees are more likely to come into estrus during times when food is readily available Anderson et al.
The majority of chimpanzee reproductive behavior is promiscuous, with females mating with multiple males opportunistically during estrus, though the majority of copulation occurs during the day period of maximal tumescence Goodall There are other types of reproductive strategies that are recognized as well.
Restrictive mating, where the dominant male restricts other males from mating with estrous females in the community, consortship mating, where an adult pair leave the community for several days to weeks, and extra-group mating, where females leave their communities and mate furtively with males from nearby communities Goodall ; Gagneux et al. Chimpanzee social and mating groups do not always overlap, given the variety of reproductive situations.
This may have evolved because females have limited choice in mates after committing to a community, and the dominance hierarchy of males often dictates which males an estrous female will mate with.
By having multiple strategies, females can expand the pool of males from which they choose while not losing the important support of the males in their communities Gagneux et al. In chimpanzees, the majority of parental care is the responsibility of the mother and is critical to the survival and emotional health of youngsters Goodall Chimpanzee infants and juveniles benefit from the close relationship with their mothers in terms of food, warmth, protection, and the opportunity to learn skills.
Chimpanzee newborns and mothers are in constant ventral-ventral contact for the first 30 days of life. During the newborn period, chimpanzees are helpless to survive without maternal support and though they have a firm grasping reflex, it is not strong enough to support the infant for more than a few seconds at a time. During the first year of life, infant chimpanzees maintain almost continual contact with their mothers.
By the age of two, they begin to travel and sit independently within five meters of their mothers and this corresponds to a decrease in nursing and the onset of independent eating and play behavior Bard ; Coe Not until three years of age do young chimpanzees venture more than five meters from their mothers, and between ages four and six, the period of infancy ends with weaning Bard During the juvenile period, from about six to nine years old, chimpanzees remain close to their mothers but play independently and have greater social interactions with other community members.
Adolescent females spend some of their time moving between groups and are supported by their mothers during agonistic encounters while adolescent males spend more time with adult males in social activities such as boundary patrols and hunting parties Bard Visual and vocal communication are important to chimpanzee society. A suite of facial expressions, postures, and sounds function as signals during interactions between individuals and groups Goodall Chimpanzees have particularly expressive, hairless faces and facial expressions play an important role in close-up communication between individuals.
Body position and stance also convey information to other individuals. Submissive positions include extending the hand, crouching, and bobbing while aggressive positions usually involve an individual trying to appear larger than he is by swaggering bipedally , hunching his shoulders, and waving his arms Goodall Adult chimpanzees will also drum on the trunks of trees, by beating their hands and feet against large trees, for a dramatic display.
Vocal communication also conveys a wide variety of emotional states and intentions and often serves to affect the behaviors of those that hear the calls.
Distance calls are used to draw attention to danger or food sources for other community members as well as establish location of other groups in the area Goodall Highly distinctive behavioral differences between populations of chimpanzees have been observed and documented.
These behavioral differences between communities include 39 different patterns of tool-use, grooming, and courtship behaviors and are classified as cultural differences Whiten et al.
Behaviors are classified as culture if inter-generational transmission of behavior occurs through social or observational learning to become a population level characteristic. That is, these behaviors are not linked to genetic differences among subpopulations nor are they related to ecological differences between study sites. While some behaviors are species typical, such as nest building, others are far from uniform across chimpanzee populations.
Termite or ant fishing, which may be the most famous examples of chimpanzee tool use are seen only in some populations while nut cracking behavior is seen only in West Africa McGrew ; Whiten et al. Primate Factsheets: Chimpanzee Pan troglodytes Behavior.
With only , to , left in the wild and about individuals in zoos in the United States, chimpanzees are among the most threatened primates in Africa for many reasons Goodall Central chimpanzees are the most numerous, with about 80, found in Gabon and Congo, eastern chimpanzees number about 13, though the estimates from DRC are very rough, and western chimpanzees are very patchily distributed with no more than 12, remaining Oates Several synergistic factors have led to the decrease in chimpanzee populations across Africa and some of the most salient threats include hunting, habitat loss and degradation due to industrialized logging and human population growth, and disease Kormos ; Walsh et al.
Even in Gabon and Congo, widely considered stronghold countries for chimpanzees, populations are declining at a rate of at least 4. Deforestation in the tropics has multiple causes including agricultural expansion, overgrazing, fuelwood gathering, commercial logging, and infrastructure and industrial development Rowe et al.
Particularly problematic in Africa is industrialized logging, which compromises the habitat in which chimpanzees thrive, both directly and indirectly. Direct consequences of logging include the loss of trees, but the indirect threats are more far reaching and include soil erosion, loss of biodiversity , climate change, desertification , watershed degradation, landscape fragmentation due to roads, and facilitation of access by settlers who convert logged forest into agricultural areas Rowe et al.
The roads that are created are particularly of concern because they provide access to once isolated forests that can then be exploited for resources, both floral and faunal. Human population growth is another underlying factor of wild chimpanzee vulnerability.
With population growth rates increasing, food production miserably inadequate, and political and economic insecurity a fact of life, Africans are struggling to meet short-term needs at the expense of chimpanzees Butynski Demand for land for housing, development of infrastructure, agriculture, and grazing animals indirectly threatens chimpanzees because of forest loss. The need for forest products for subsistence usage such as vines for basketry, medicine, collection of food, and firewood also degrades chimpanzee habitat Conserving the Chimpanzees of Uganda As human populations explode so will the development of infrastructure and habitat degradation will follow.
Some possible suggestions to mitigate habitat degradation due to logging include responsible forest practices, including selective felling , use of pitsaws rather than power saws, and restrict access for loggers to only a few days per week Endroma et al.
Sustainable forestry practices that include selective logging and limited extraction can not only stop negative effects of logging on chimpanzee populations, but actually improve population densities because of higher abundance of fruits in successional plots and a decrease in mechanized logging equipment Plumptre and Grieser Johns Establishment of strict protection areas in high priority conservation areas thereby precluding logging activity is another possible mechanism to decrease habitat loss.
This solution is only possible, though, if alternative income strategies are provided for the communities that depend on logging for income.
As humans come into contact with chimpanzees more readily through bushmeat availability and open-access logging roads, the spread of zoonotic diseases such as Ebola , a deadly hemorrhagic fever, threaten both human and ape populations. In some areas, Ebola is a concern for the viability of chimpanzee populations because of its acute deadliness and misunderstood etiology Walsh et al. Other infectious diseases that threaten chimpanzees include the common cold, pneumonia, paralytic poliomyelitis, tuberculosis, chicken pox, and influenza among others Butynski An epidemic of any of these diseases could cause massive mortality within a small population and potentially cause rapid extinction of subspecies and species.
In , multiple infants were killed and many adults paralyzed in an outbreak of a paralytic disease probably polio at Gombe Goodall Frequent close contact due to increasing human populations or even tourists, guides, and park personnel may increase the risk of transmitting these diseases to chimpanzees, and the problem could worsen.
Limiting human proximity to chimpanzees as much as possible will decrease the likelihood of infectious diseases traveling between humans and chimpanzees.
In areas of high tourism, research activity, and where interactions between chimpanzees and local communities are common, stricter precautions are needed to protect chimpanzees from human diseases as well as safeguard humans against novel chimpanzee diseases Butynski For tourists and researchers that come into close contact with chimpanzees, certain regulations should be implemented and adhered to including regular screening for and vaccination against diseases such as tuberculosis and proper sanitation including hand-washing, disinfectant footbaths, or surgical masks within a certain distance of the apes.
Though the trade of chimpanzees is restricted, the unstable political situation and rampant corruption in many countries translates into little enforcement Ammann The increase in availability of firearms over the last few decades has greatly increased poaching efficacy.
Modern firearms make poaching these large, strong apes much easier and more successful than when using traditional weapons. For hunters that poach chimpanzees for commercial purposes, the use of guns ensures a higher yield as well, so populations may be dropping exponentially faster than if traditional weapons were used.
Moreover, because of their life history characteristics, chimpanzees are more likely to go extinct due to hunting than other primates.
Those primates most vulnerable to hunting pressures are those dependent on old-growth forest, that weigh at least 4 kg 8. Especially troubling is the problem of orphaned chimpanzees. Poachers are only interested in adults for their meat, but killing an adult female with dependent offspring ensures that those infants or juveniles will either be sold into the pet trade or die because they lack the support of their mother so integral to chimpanzee development.
Another factor that has made hunting easier is the spread of industrialized logging. Commercial logging transforms roadless forests into major thoroughfares which can be easily accessed by commercial hunters. Poachers can find their own transportation or hitchhike on logging trucks into the forests and loggers, after their daily work, can stay to hunt before driving back to the village Ammann Not only does the infrastructure provided create ease of access to forests for poachers including restricted natural areas and parks , but an influx of men working for logging companies drives up the demand for bushmeat, which is much less expensive than other protein sources available at markets in logging towns Walsh et al.
More than just providing access to areas where chimpanzees are available, logging companies provide guns, materials for snares, transportation to and from hunting areas as well as transportation of carcasses to markets in large cities. Employees of some logging companies are involved at every step of the bushmeat process from the tools to make the guns to the consumption of the meat Ammann If the bushmeat trade is to stop, there are some very important and difficult objectives that must be achieved.
First, the governments of African countries have to implement sustainable use policies for the natural resources in their countries and global institutions such as the World Bank must begin to offer financial and political incentives to implement environmentally responsible development projects that do not include the unsustainable use of natural resources Butynski These projects should include the development of alternate food sources for bushmeat.
Furthermore, logging companies should be held to corporate codes of conduct and responsibility by western consumers. Logging companies with leases to forests are usually from developed countries; certainly international pressure on these companies could be great enough to change some of their policies.
Certification programs based on sustainable techniques and extraction practices are another option to decrease bushmeat hunting Butynski Reviewed by independent parties, the criteria of certification can involve control of the bushmeat trade and maintenance of biodiversity as central parts of the accreditation process.
Education programs and materials at zoos and on the internet can get the message across to western consumers that purchasing uncertified tropical woods from Africa has deleterious effects on biodiversity, chimpanzee habitat, as well as the people of Africa. Enforcement of protected areas and the laws regarding the trade of chimpanzees would also affect the number of chimpanzees killed for bushmeat. Guards and park patrols are needed to deter hunters from entering protected areas in search of chimpanzees.
Finally, sanctuaries for orphaned chimpanzees are necessary to rehabilitate the infants and juveniles and save them from an unnatural life in a home.
Chimpanzees typically direct their aggressive and sometimes predatory behavior toward children because the animals are more fearful of larger human adults, especially men, according to National Geographic. Chimps have also snatched and killed human babies.
Most of the time these are isolated and seemingly reckless attacks by individual chimps, but one chimpanzee in the s killed seven children before he was killed by humans, National Geographic reported.
Captive or pet chimpanzees attack people far more often than their wild kin, because they can lose their fear of people altogether. During attacks, chimps will target a person's face, hands, feet and genitals. The Jane Goodall Institute UK noted that pet chimpanzees are destructive and too dangerous to be kept as part of the family, and that it is difficult to keep them stimulated and satisfied in a human environment.
Chimpanzees are highly social animals and live in communities of between 10 and individuals, according to the Max Planck Institute for Evolutionary Anthropology in Germany. They live in fusion-fission societies where the community breaks up into small subgroups fission that travel separately and sometimes come together fusion.
Males will stay in their birth community, while females can move into neighboring communities once they are old enough to breed. Male chimpanzees defend their community's territory against neighboring chimp communities and will kill members of other groups.
Chimpanzees are the only species other than humans to carry out coordinated attacks on each other , Live Science previously reported. This warlike behavior, documented by famed primatologist Jane Goodall , among others, challenged the notion that warfare is a development of modern humans. Related: Chimps are naturally violent, study suggests. Male and female chimpanzees mate with multiple partners throughout the year. Mating occurs more frequently than required for breeding purposes and serves social functions as well, such as developing bonds between individuals, according to ADW.
Males may sometimes secure exclusive access to females for reproduction by preventing other males from mating with the female, although females also have some mate choice. Much variation has been observed in all aspects of chimpanzee social structure and reproductive strategies, according to the Max Planck Institute for Evolutionary Anthropology. Females give birth to a single baby chimpanzee or occasionally twins. A baby chimpanzee is about 4. As they grow up, infants begin to walk on their own but continue to hitch a ride on their mothers, increasingly on her back, until they are weaned at about 4 to 5 years old.
Chimpanzees typically live up to about 50 years in the wild, according to the IUCN. They can survive longer in captivity, where one female lived into her 70s. However, they have a discontinuous distribution, which means populations can be separated by great distances. Chimps are mainly associated with tropical rainforests, but they occupy a variety of different habitats, including swamp forests and savannas.
They also live at varying elevations and can be found in forests on mountains up to 9, feet 2, m above sea level, according to ADW.
Chimpanzees are considered an endangered species and at risk of becoming extinct. Their population is declining and there are estimated to be fewer than , chimpanzees left in the wild, according to the IUCN. The major threats to chimpanzees are poaching, habitat loss and degradation, and disease.
We also both play, have complex emotions and intelligence, and a very similar physical makeup. What many people may also not know, is how vital this taxonomy or the systematic classification of organisms is to Dr. It was in fact Dr. Louis Leakey in Kenya, which lead to her initial research in Gombe, Tanzania.
Leakey was trying to understand early humans, and because his only point of reference was fossilized early human remains and other preserved cultural materials, he could not completely understand what early human behavior may have been like. When he met Jane, with her passion for and knowledge about animals, he knew she would be the perfect candidate to study chimpanzees — our closest living primate relative — from which he could conclude what behaviors were likely inherent to our most recent common ancestor and earlier humans.
Zinda fishing for termites in Gombe National Park, Tanzania. In her research, Dr. Goodall made a revolutionary discovery when she observed that the chimps in Gombe were making and using tools.
It was groundbreaking because it meant redefining everything that scientists thought they knew about what separated humans and chimpanzees! It has also lead to the revelation that other animals also make and use tools, have emotions, intelligence and sentience.
Want to know more and to support our ongoing research in Gombe, now the longest running wild chimpanzee study in the world? Become a Gombe Science Hero! Find out more and get involved here. The Jane Goodall Institute is a global community conservation organization that advances the vision and work of Dr. Jane Goodall.
By protecting chimpanzees and inspiring people to conserve the natural world we all share, we improve the lives of people, animals and the environment. Everything is connected—everyone can make a difference. She has been passionate about the environment and conservation since her parents raised her spending summers camping in the U.
S National Parks. She hopes to someday work around the world on women's issues and environmental conservation. Upon her graduation in May she would like to become the proud owner of a dog.
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