Clever Monkeys Part 1/6 Part 2/6 Part 3/6 Part 4/6 Part 5/6 Part 6/6

Clever Monkeys Part 1 Part 1/6 What to look for… Similarities to us

Primates in the clip Marmosets (Platyrrhini Parvorder) Tamarins (Platyrrhini Parvorder)

Primate Physical Traits – Limbs A tendency towards erect posture. Hands and feet possess grasping ability. Features of the hands and feet: 5 digits on hand and feet Opposable thumb Precision grip possible only with some Primates Partially opposable great toe Tactile pads enriched with sensory nerve fibers at the ends of digits

Primate Physical Traits – Teeth Omnivorous Incisors for biting and cutting; premolars and molars for chewing and grinding Dental formula Old World anthropoids have two incisors, one canine, two premolars, and three molars on each side in both upper and lower jaws: 2.1.2.3 (32 teeth total)

Primate Physical Traits – Vision Stereoscopic Vision Visual images are superimposed on one another. This provides for depth perception, or the perception of the external environment in three dimensions.

Primate Physical Traits – Vision cont. Binocular Vision Vision characterized by overlapping visual fields provided for by forward-facing eyes. Binocular vision is also essential to depth perception.

Primate Physical Traits – Vision cont. Color Vision Diurnal primates have it, nocturnal ones don’t

Primate Physical Traits – Smell Primates have a decreased reliance on the sense of smell. No rhinarium = worse sense of smell

Primate Physical Traits – Locomotion Quadrupedal, walk on all fours (Baboon) Vertical clinging and leaping (Indiri) Brachiation (Gibbon) Knuckle walking (Gorilla/Chimp)

Primate Physical Traits – Neocortex The Neocortex makes up the outer portion of the Cerebrum. The larger the Neocortex the more social the animal. Human Cerebrum Gibbon Wolf

Primate Physical Traits Evolutionary Factors Changes in diet, reliance on vision, grasping hands and feet came about with arboreal settings, forward-facing eyes (facilitate binocular vision), rise of angiosperms (flowering plants)

Clever Monkeys Part 2 Part 2/6 What to look for… Basic Primate Family Unit Enculturation Learned Behaviors The Piper Plant Social Behavior Bonding Grooming Aggression

Primates in the clip Silver Leaf Monkeys (Catarrhini Parvorder) White-faced Capuchins (Platyrrhini Parvorder)

Primate Family Units The basic social unit among all primates is the female and her infants. Except in species in which monogamy or polyandry occur, males do not participate in rearing offspring. The mother-infant relationship is often maintained throughout life. Primates produce only a few young in whom they invest a tremendous amount of parental care (K–selected) (contrast r-selected)

Enculturation Cultural behavior is learned; it is passed from generation to generation through observation and instruction. Nonhuman primate infants, through observing their mothers and others, learn about food items, appropriate behaviors, and how to use and modify objects to achieve certain ends. More complex, chimpanzee culture includes tools such as termite fishing sticks and leaf sponges.

Social Behavior Bonding The role of bonding between primate mothers and infants was demonstrated in experiments at the University of Wisconsin. Psychologist Harlow raised infant monkeys with surrogate mothers made of wire or a combination of wire and cloth. Other monkeys were raised with no mother at all.

Social Behavior Affiliative Behavior Hugging, kissing and grooming are used in reconciliation. Relationships are crucial to nonhuman primates and the bonds between individuals can last a lifetime. Altruism, behaviors that benefit another while posing risk to oneself, are common in primate species.

Social Behavior Grooming Picking through fur to remove dirt, parasites, and other materials that may be present. Social grooming is common among primates and reinforces social relationships.

Aggressive Interactions Dominant actions can keep subordinates away from food and using weight loss and poor nutrition, threatening reproductive success of subordinates Competition can result in injury and death

Intergroup Aggression Primate groups are associated with a home range where they remain permanently. Within the home range is a portion called the core area, which contains the highest concentration of predictable resources, and it’s where the group is most frequently found. The core area can also be said to be a group’s territory, and it’s the portion of the home range defended against intrusion.

Clever Monkeys Part 3 Part 3/6 What to look for… Natural selection acting on behavior? Reproductive Behaviors and Strategies Sexual Selection Benefits of Group Living

Primates in the clip Toque Macaques Golden Lion Tamarin Golden snub-nosed monkey Emperor Tamarin Proboscus monkey Douc Langur of Cambodia monkey

Natural Selection acts on Behavior “A need to try everything is an extraordinary way to survive in the jungle. Leaves can cure you or kill you”

The Evolution of Behavior Behavior constitutes a phenotype, just like observable, physical traits do. Individuals whose behavioral phenotypes increase reproductive fitness pass on their genes at a faster rate. Genes do not code for specific behaviors (i.e. aggression, cooperation, etc.) Natural selection acts on genetic factors shaped by ecological setting of past and present

Sexual Selection A type of natural selection that operates on one sex, usually males. Long-term, this increases the frequency of traits that lead to greater success in acquiring mates. Sexual selection in primates is most common in species in which mating is polygynous and male competition for females is prominent. Sexual selection produces dimorphism with regard to a number of traits, most noticeably body size.

Benefits of Group Living Group living exposes animals to competition with other group members, so why not live alone? Costs of competition are offset by the benefits of predator defense provided by associating with others. Group living evolved as an adaptive response to a number of ecological variables.

Clever Monkeys Part 4 Part 4/6 What to look for… Adaptive behavior Intra and Inter-species language and symbols

Primates in the clip Howler Monkeys (Platyrrhini Parvorder) Black and White Colobus (Catarrhini Parvorder) Red Colobus (Catarrhini Parvorder) Guenon (Catarrhini Parvorder) Sooty Mangabey (Catarrhini Parvorder) Diana Monkey (Catarrhini Parvorder) White-faced Capuchin (Platyrrhini Parvorder) Patas Monkey (Catarrhini Parvorder)

Language Nonhuman animals haven’t been considered capable of communicating about external events, objects, or other animals. It has been assumed that nonhuman animals use a closed system of communication, where vocalizations don’t include references to specific external phenomena.

Koko the Gorilla The Gorilla Foundation Clip of Koko Want to volunteer or get a job with Koko at Stanford? Go Here Koko and Penny Patterson

Clever Monkeys Part 5 Part 5/6 What to look for… Dominance Hierarchies Communication methods Stress-related diseases in large societies Benefits of group living

Primates in the clip Baboons (Catarrhini Parvorder) Geladas

Dominance Hierarchies Many primate societies are organized into dominance hierarchies that impose order and establish parameters of individual behavior. Higher-ranking animals have greater access to preferred food items and mating partners than lower ranking individuals. Dominance hierarchies are sometimes called “pecking orders” that change throughout one’s life and are learned

Factors that Influence Dominance Status Sex Age Aggression Time in the group Intelligence Motivation Mother’s social position

Communication Basics… Any act that conveys information to another individual. Frequently, the result of communication is a change in the behavior of the recipient. Communication may be the result of involuntary processes or a secondary consequence of an intentional action.

Communication Raised body hair is an example of an autonomic, or unintentional, response. Gestures, facial expressions, and vocalizations are examples of deliberate communication. The fear grin, seen in all primates, indicates fear and submission. Grooming serves to indicate submission or reassurance. Displays communicate emotional states.

Benefits of Group Living Predation Primates are vulnerable to many predators, including snakes, birds of prey, leopards, wild dogs, lions, and even other primates. Where predation pressure is high, large communities are advantageous. These may be multi-male, multi-female groups or congregations of one-male groups.

Benefits of Group Living Relationships with Nonpredatory Species Many primate species associate with other primate and nonprimate species for various reasons, including predator avoidance.

Benefits of Group Living Dispersal Members of one sex leave the group in which they were born when they become sexually mature. Individuals who leave find mates outside their natal group, so dispersal is believed to decrease the likelihood of close inbreeding.

Clever Monkeys Part 6 Part 6/6 What to look for… Tool usage Intelligence

Primates in the clip Bearded Capuchin (Platyrrhini Parvorder)

Intelligence Mental capacity; ability to learn, reason, or comprehend and interpret information, facts, relationships, and meanings. The capacity to solve problems, whether through the application of previously acquired knowledge or through insight.