Primate Studies 3 Behaviors - IU

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Primate Studies 3 Behaviors - IU Powered By Docstoc
					The first social interactions of a newborn primate are
with mother. The mountain gorilla is very careful to
support her young infant as it clings to her. All
primates seek contact with mother as soon as they
are born -- and most are able to cling on their own
within a day or two of birth.
• Unlike many other animals,
  primates do not leave their
  infants in a nest or other
  protected area. Instead,
  mothers carry their infants
  wherever they go. Infants
  may cling to the belly or, as
  this young uakari is doing,
  ride on mother's back.

• Scientific name: Cacajao
  uakari -- wah-CAR-ee
• When they are at rest, mother and baby usually
  sleep in ventral-ventral, or belly-to-belly, contact.
  But a curious infant, such as this spider monkey,
  spends as much time as possible looking around at
  the world.
• Scientific name: Ateles geoffroyi
• Meeting the other members of the social group is
  an important experience for young primates. Here a
  juvenile spider monkey is contacted by the new
• Juvenile spider monkey looks at infant on mother's
  Juvenile refers to the years between infancy and
  adulthood. For spider monkeys this is 1 - 4 years
 For primates, as all other mammals, mother is a source of
 food. This young Japanese macaque nurses while its mother
 is groomed by another monkey. At first, mothers carefully
 guard their infants, and may prevent others from touching the
 new baby. Interested animals are allowed near the infant only
 after reassuring the mother of their friendly intentions.

Mother Japanese macaque holds nursing infant while troop
member grooms her.
Scientific name: Macaca fuscata
macaque -- ma-KACK
Contact with the mother is an important first social
            experience for humans, too.
• Although all primates live in social groups, the
  nature of those groups differs between species.
  Group size, the number of adult males and adult
  females, and who does most of the breeding all
  vary between species.
• The siamangs
  shown here live in a
  family unit
  consisting of an
  adult male, adult
  female and their
  young offspring.
  This is similar to
  the basic living unit
  of many humans --
  mom, dad and the

• Family group of
  siamangs showing
  adult male (top), adult
  female (middle) and
  their offspring (bottom).

• Scientific name:
  siamangs -- SI-a-mangs
• Other primates live in groups with only one
  adult male and several adult females plus their
  offspring. In a gorilla group the adult male,
  called a silverback, fathers the offspring of all
  the females living with him.

       Group of mountain gorillas in African forest.
• The single male group structure is also found in
  some species of monkey. Here the large male
  hamadryas baboon walks at the front of a group of
  adult females.
   A group of female hamadryas baboons follow the large adult male
   in a zoo enclosure.
   hamadryas -- hom-uh-DRY-us
   Notice the genital swellings on one female. These indicate sexual
• Multi-male groups are also common among the
  primates. Chimpanzee bands are made up of
  several adults of both sexes and their offspring.
  Such bands are temporary associations of animals
  who live in a larger community. Relationships
  between adult males are very important in these

 Three male chimpanzees sit together. Photo taken in a zoo group.
 Scientific name: Pan troglodytes
• Some species of monkeys, such as these
  stumptail macaques, also live in groups with
  more than one adult of each sex. Relationships
  among adult females are most important in the
  social structure of these stable troops
    A group of stumptail macaques feeding.
    Scientific name: Macaca arctoides
    macaques -- ma-KACKS
• All primates need to learn
  how to be a successful
  member of a social group.
  Young animals spend a
  great deal of time learning
  social skills through play.
  This young chimpanzee
  invites a companion to
• All primates play. Here a group of lemurs engage in
  the most common form of play. This activity,
  characterized by chasing and wrestling, is called
  rough-and-tumble play. It seems to allow young
  animals to learn their own strengths and weaknesses,
  as well as that of their peers.
        Group of ring-tailed lemurs wrestling.
        Scientific name: Lemur catta
        lemurs -- LEE-mers
• Social play occurs when two or more
  individuals engage in a behavior that has no
  apparent serious purpose, although it may
  resemble the behaviors used by adults in
  their social lives. Humans often call this
  playing games.
• For most primates, play involves physical
  contact. Here are two chimpanzees wrestling.
• Gorillas like to wrestle too
• Play frequently
  occurs between
  animals of
  different sizes.
  These gorillas are
  engaging in rough
  play, but the
  smaller animal
  rarely gets hurt in
  a play bout.

                        A young lowland gorilla plays with an older
                        juvenile in a zoo.
                        Scientific name: Gorilla gorilla gorilla
• Even in the roughest form of play, animals are seldom
  hurt. Older animals know that if a younger animal is hurt or
  scared, a scream can bring mother running to defend her
  baby. This interaction between a juvenile chimpanzee and
  an infant may look dangerous, but both animals know it is
  only play.

    In the foreground, a juvenile chimpanzee drags an infant. Adult female
    chimpanzees in background appear unconcerned, while another infant
    watches the play bout.
• Knowing the intentions of other group
  members is vitally important to social
  animals. Primates use all the senses --
  sight, smell, hearing, taste and touch --
  in communicating with each other.
• All primates rely heavily on vision to explore their world. It is not
  surprising that facial expressions are an important
  communication tool. The youngest animals quickly learn to
  recognize the play face. The rhesus macaques, shown here with
  mouth open, demonstrate the play face seen in all monkeys,
  apes, and even humans at play.

        Two rhesus monkeys wrestle.The animal on top (with head
        upside down) shows the open mouth play face.
        Scientific name: Macaca mulatta
        rhesus macaques - REE-sus ma-KACKS
• Friendly intentions are also being communicated here
  by the rhesus monkey looking towards the camera. She
  is lip-smacking, an active facial expression that invites
  another animal to join the group.
     A group of rhesus monkeys. One animal looks toward the camera.
     Photo taken in a zoo enclosure.
     To lip-smack, pucker up your lips, and open and close t hem
• Primates are also very good at communicating when
  they are not happy about a social interaction. Here
  another rhesus monkey screams and grins. This
  bared teeth expression is usually shown by the loser
  in a less-than-friendly encounter.
 A mother rhesus macaque at center with her offspring responds to
 threats from two other monkeys.
 • Many primate species
   have unusual faces.
   This golden snub-nosed
   monkey from China
   shows an eye-catching
   combination of
   contrasting facial

Closeup of face of a golden snub-nosed monkey.
The flaps of skin at the corners of the mouth are a normal facial feature of
adult males in this species.
• Scientists think one purpose of such a face is that it
  permits other animals to get a very clear view of all
  facial expressions. The yawn has several meanings
  for primates. A yawning animal is more likely to be
  nervous than tired.

  A golden snub nosed monkey yawns, showing large canine teeth.
  Scientific name: Rhinopithecus roxellanae
  Most adult male higher primates have large canine teeth. Humans are an
• Primates pay close attention to the body language of
  other members of their group. Here a chimpanzee
  begins an action that is also performed by humans.

     An adult chimpanzee with back to camera begins to bow to a
     second chimpanzee.
• The bow is a sign of submission that indicates to the
  animal receiving it that he or she is dominant. Most
  primate groups have a dominance hierarchy. Lower
  ranking animals can avoid fights with higher ranking
  animals by performing a formal sign of submission,
  such as a bow, when tensions are high.
• Primate body language can be very impressive. Here an adult
  male chimpanzee, on the left, stands with all his hair on end.
  This is called piloerection -- it makes an animal look larger to the
  nearby audience.

        Three chimpanzees in a zoo enclosure. The adult male
        on the left facing the camera is getting ready to run by
        the animals on the right.
• Next, the chimpanzee male charges past the group members
  he is trying to impress.

    Adult male chimpanzee runs past two other chimpanzees. Edge
    of enclosure is marked by moat in the foreground.
• Chimpanzees may also charge directly at
  another individual. This kind of display does not
  signal the beginning of a fight -- only an attempt
  to impress another animal. In this picture, two
  males are confronting each other.

  Two adult male chimpanzees confront each other. Animal in the
  foreground stands bipedally and is piloerected.
• In a tense situation, animals usually can tell when a
  conflict is about to occur. Here one chimpanzee
  chases a displaying opponent away.
Three chimpanzees on climbing structure in zoo enclosure. Piloerected
animal in front had been displaying. Male in center is chasing him away.
• Body posture also signals when an opponent no
  longer wants to fight. This screaming chimpanzee's
  lowered body position indicates submission.

          Screaming chimpanzee crouches on the ground.
• These lemurs are using another kind of body language -
  - signaling with their tails in the air. Tail position can
  communicate alertness and self-confidence.

 Three ring-tailed lemurs from a captive group stand with tails in
 'question mark' position. Animals are wearing identification collars.
• Body language is also important in humans. A hand-
  shake is a common expression of goodwill between
• Primates use their
  sense of smell to
  communicate, too.
  Here a sifaka leaves
  a scent mark on a

A sifaka (related to the lemurs) rubs a scent-producing anal gland
against the bark of a tree.
Scientific name: Propithecus verreauxi
sifaka -- sih-FAHK-ah
• A cotton-top tamarin sniffs at a scent left by another
  individual in a captive group of monkeys. Scents may
  mark territorial boundaries, let other animals know
  where to find food, or communicate when animals of
  the opposite sex are ready to mate.
 A cotton-top tamarin, a small South American monkey, sniffs at an odor-
 containing vial. This animal lives in a captive group used in studies of
 Scientific name: Saguinus oedipus
 tamarin -- TAM-ah-rin
• Primates use sound to communicate as well. Many animals have
  complex calls that let others know of danger, or when they are
  intruding on another group's territory. This howler monkey gets its
  name from the loud call it produces.

 A brown howler -- a South American monkey -- faces right as it calls from
 a tree. Notice the enlarged lower jaw which allows this monkey to produce
 a loud, resonating call.
 Scientific name: Alouatta fusca
• Most primates live in
  forests, and are able to
  produce some calls that
  carry long distances, such
  as hooting by this
  chimpanzee. Softer sounds
  are used when group
  members are near each
  other. Humans use sound
  to communicate when they
• Hear a chimp laugh

                               Adult male chimpanzee
                               stands bipedally and hoots.
           More Primate Sounds

Gorillas           Bonobo        Orangutan
• Touch is a very important sense for primates.
  Social animals have many friendly interactions
  throughout the day -- and most involve some form
  of touch. Mothers and infants spend a lot of time in
  contact, as do play partners, sexual partners, and
  other members of a social group.
• These young macaques are using in a play bout a form of
  touch used by adults to initiate a sexual interaction. The
  animal standing on four feet is presenting her rear end to
  a partner. He responds by touching her hips and
 Two young macaques from a mixed species captive group. The female
 stands quadrupedally while the male stands behind her.
• An adult female stumptail macaque presents to an
  adult male. He responds by touching her rear, and
  visually inspecting it for signs that she is in her
  fertile period and thus ready to mate.
An adult female stumptail macaque presents her genital area to an adult
male. He will look, smell, touch and even taste her secretions to learn if she
is ready to mate.
Primates rely on many signals to determine the reproductive state of
animals of the opposite sex.
• Here a female chimpanzee presents to a male. The
  swollen skin around her genitals gives a visual
  signal that she is fertile.
A female chimpanzee (lying on her side) presents her genitals to an adult
• A typical copulation or mating in most primates involves the
  male mounting the female from the rear

          A male Japanese macaque mounts a female.
• The female Japanese macaque reaches back and
  looks at her partner during their mating.

Later in the same sequence, the female Japanese macaque looks over her
shoulder at the male. This often occurs when the male ejaculates.
• Physical contact between animals is a part of most friendly
  interactions in primates. Here two Japanese macaques sit
  together in close contact
• These golden snub-
  nosed monkeys show
  the same pattern of
  contact. This type of
  touch, called a huddle,
  can occur when
  animals are resting or

Two golden snub-nosed monkeys, living in a Chinese research facility,
Monkeys do huddle in cold weather for warmth. In the wild snub-
nosed monkeys survive snowy winters. However all monkeys huddle,
even in the hottest weather, for social contact
• Another very important friendly physical contact is social
  grooming. Here one monkey grooms a partner who is offering
  her chest to be groomed.

 A female Japanese macaque lies on her back while another animal
 grooms her.
• When animals groom,
  they look through the
  fur and remove any
  debris they find, such
  as dirt, dead skin or

                      An adult female hamadryas baboon (an African
                      monkey) grooms an adult male.
• Social grooming not
  only helps animals
  keep clean; it
  reinforces bonds
  between related
  animals and other
  members of a social

     Three long-tailed macaques sit together. The adult female in
     the center grooms a juvenile on the right.
     Scientific name: Macaca fascicularis
• In a group of monkeys, such as these long-tailed
  macaques, mothers groom their infants; females groom
  males; males groom females; older offspring groom
  their mother. All combinations of grooming partners
  are possible.
    A large group of long-tailed macaques, including some mothers
    holding infants on their bellies, sit together. An adult male in the top
    row is being groomed by two other animals.
• In a group of monkeys, such as these long-tailed
  macaques, mothers groom their infants; females groom
  males; males groom females; older offspring groom their
  mother. All combinations of grooming partners are possible.

     A large group of long-tailed macaques, including some mothers
     holding infants on their bellies, sit together. An adult male in the top
     row is being groomed by two other animals.
• Social animals don't always get along with the
  members of their group. Fights and other forms of
  aggression are a common occurrence in primate
• Unfriendly behavior usually begins with a threat. Here an adult
  gorilla shows the body posture and facial expression that lets an
  opponent know a fight is possible.

  Adult female lowland gorilla (standing), living in a zoo group, stares at
  an opponent off-camera. A juvenile sits near her.
  This is called a pursed lip threat posture. Look at the stiff arms and the
  tight position of the lips.
• Staring at an opponent is often part of a threat. This rhesus
  macaque shows the open mouth threat face used by many
  species of monkey.

   A female rhesus macaque holding an infant stares off camera at an
• Other parts of the body can be shown as part of a threat. Here a
  marmoset flashes the colors on her rear end; other group
  members know this a threat.

  A pygmy marmoset, a South American monkey, viewed from the rear.
 • Not all threats lead to fights. Most of the time the
   opponent will leave or show submission. Sometimes
   threats are just ignored. But fights do occur. Here an
   adult male chimpanzee attacks a female carrying an

A fight between chimpanzees living in a zoo group. A female holding an
infant, in the foreground, is attacked by an adult male behind her. She is
screaming in submission.
• Fights can have serious consequences. A long-tailed
  macaque shows injuries received in a fight. Animals
  can be badly hurt or even die as the result of fighting.
   A long-tailed macaque, on the right, shows wounds on the shoulder.
   This type of slash wound can be inflicted by adult males with their
   large canine teeth. In most primate species, animals are not killed or
   even seriously injured during fighting but a few may die later due to
   shock or infection.
• Early observers of gorillas
  were impressed with their
  threats and displays. Here
  an adult male stands on
  two legs and beats his
  chest. This gained the
  gorilla the reputation as a
  very aggressive animal.
  Actually they are among
  the most peaceful of the

   Adult male silverback mountain gorilla stands bipedally while
   displaying in an African forest.
   Gorillas use a cupped hand position to make the sound associated
   with chest beating.
• The chimpanzee can be very aggressive. However, as
  with all primates, most aggression does not lead to
  serious consequences. Here a male shakes a branch
  as part of a display. If his opponent does not back
  down, a fight may occur.
  A piloerected adult male chimpanzee shakes a branch while another
  animal watches.
  While many conflicts between chimpanzees involve only noisy displays,
  chimpanzees are the one primate besides humans known to kill adult
  animals of the same species during a fight.
• Often fights are followed by reconciliation or making
  up by the opponents. Animals who continue to live in
  the same group may make an effort to repair the
  social relationship interrupted by their fight. This
  usually involves some form of friendly touch, such as
  grooming, or even just sitting next to each other while
    Two mountain gorillas feed next to each other in the forest.
• Fights between groups also occur. Here members of two troops
  of green monkeys face off. Again, threats and displays are the
  most likely form of aggression.

Members of two groups of African green monkeys threaten each other.
Scientific name: Cercopithecus aethiops
• All the members of a group may get involved in an intertroop
  fight. These rhesus macaques threaten each other. In this
  species, females are often at the front when aggressive
  encounters with other groups occur
 Two large troops of rhesus monkeys threaten each other. Notice that
 several females carrying infants are in the front ranks.
• A fight between groups may involve members of both sexes.
  Males and females are at the front in this conflict between
  neighboring hamadryas baboon troops.

  Hamadryas baboon groups come to blows at an African water hole.
       Adult males have long fur on their face and shoulders.
• Sometimes intergroup fights involve males only.
• Knowing all the members of its group is important to
  a social animal. New animals may migrate into a
  group from other areas -- but most new members of
  a group are born there.
• Everyone is interested in new babies. This adult male
  gorilla gently touches an infant.

 Adult male lowland gorilla touches a young infant in a zoo enclosure.
• In most species,
  mothers do most of the
  child care. However in
  some species, fathers
  may carry infants most
  of the time. Here a
  tamarin male carries a

   Adult male saddleback tamarin carries a youngster on his back.
   Scientific name: Saguinus fuscicollis
• Juveniles also spend a lot of time with infants. These young
  gorillas take turns carrying the newest member of their social

  A rare photo. Twin male gorillas born in a zoo carry a younger animal
        who had been adopted by an adult female in their group.
• An adult female
  chimpanzee plays with
  a young animal. The
  two animals are not
  related. This kind of
  behavior, a friendly
  interaction between an
  adult female and an
  unrelated youngster, is
  called aunting behavior
An adult female chimpanzee wrestles with an unrelated youngster.
This is also called alloparenting. It occurs whenever someone other than
the mother carries or defends a young animal. Juveniles, especially
females, are most likely to do this, but other group members may also
show protective behavior towards infants.
• Grandparents may also have a special interest in
  the next generation. All primates must have the
  ability to adapt to changing social relationships.
  They begin learning social skills at birth and
  continue to practice them throughout life.