Who Is Who Among the Primates ? •  •  •  • 

How Humans View Their Place in Nature Humans are Mammals, Specifically: Primates Abbreviated Taxonomy of the Primates Great Apes, Our Closest Non-human Relatives –  Orangutan (Pongo pygmaeus) –  Gorilla (Gorilla gorilla) –  Chimpanzee (Pan troglodytes) –  Bonobo (Pan paniscus) –  No model species for humans

•  Humans Are Special in Anatomy and Behavior •  Several Uniquely Human Traits Revolve Around Sexuality and Raising the Young

Sculpture portraying the Haida myth of a raven coaxing the (fearful) first humans out of a clam shell.  Carved by Bill Reid from one block of yellow cedar.

Displayed at the Museum of Anthropology in Vancouver/British Columbia.

Who Is Who Among the Primates ? •  •  •  • 

How Humans View Their Place in Nature Humans are Mammals, Specifically: Primates Abbreviated Taxonomy of the Primates Great Apes, Our Closest Non-human Relatives –  Orangutan (Pongo pygmaeus) –  Gorilla (Gorilla gorilla) –  Chimpanzee (Pan troglodytes) –  Bonobo (Pan paniscus) –  No model species for humans

•  Humans Are Special in Anatomy and Behavior •  Several Uniquely Human Traits Revolve Around Sexuality and Raising the Young

Family Tree of Eutherian (placental) Mammals.  The shrew-like insectivore stock were small and presumably secretive animals living while dinosaurs were still dominant.

Primate Characteristics Shown in a Fossil Ape This fossil ape (named Pliopithecus and dated about 20 million years ago) shows some of the basic primate features, many of which are adaptations to living in the tree canopy. • Head with a short snout • Eyes parallel, forward • Grasping hands and feet • Flat fingernails • Erect posture • Generalized teeth • Large, complex brain

Dental Formulas of Primates. Most Primates have 32 adult teeth, although some New World monkeys have 36. Note the rounded cusps of premolars and molars.

Vertebrate Brains in Lateral View. The large overall size of the primate brain, and the over-proportionate growth of its cerebral cortex, facilitate learning and problem solving.

Who Is Who Among the Primates ? •  •  •  • 

How Humans View Their Place in Nature Humans are Mammals, Specifically: Primates Abbreviated Taxonomy of the Primates Great Apes, Our Closest Non-human Relatives –  Orangutan (Pongo pygmaeus) –  Gorilla (Gorilla gorilla) –  Chimpanzee (Pan troglodytes) –  Bonobo (Pan paniscus) –  No model species for humans

•  Humans Are Special in Anatomy and Behavior •  Several Uniquely Human Traits Revolve Around Sexuality and Raising the Young

Carolus Linnaeus, aka Carl von Linné (1707-1778), was a Swedish poet and naturalist. He introduced the binomial nomenclature (genus, species) of organisms, and is considered the “father of modern taxonomy”. His book Systema Naturae (10th ed., 1758) classified 4,400 animal and 7,700 plant species. The Lutheran archbishop of Uppsala accused him of “impiety” for placing the human among the primates.

Hierarchical taxonomic categories introduced by Carl von Linné

Taxonomic System of Extant Primates This chart is based on anatomical, biogeographic, and molecular data. It emphasizes the taxonomic groups close to humans.

Marmoset (South America)

Mandrill (Africa)

Gibbon (Southeast Asia)

Who Is Who Among the Primates ? •  •  •  • 

How Humans View Their Place in Nature Humans are Mammals, Specifically: Primates Abbreviated Taxonomy of the Primates Great Apes, Our Closest Non-human Relatives –  Orangutan (Pongo pygmaeus) –  Gorilla (Gorilla gorilla) –  Chimpanzee (Pan troglodytes) –  Bonobo (Pan paniscus) –  No model species for humans

•  Humans Are Special in Anatomy and Behavior •  Several Uniquely Human Traits Revolve Around Sexuality and Raising the Young

Orangutan (Pongo pygmaeus) The Orangutan lives in the rain forests of Sumatra and Borneo. It faces imminent extinction in the wild from poaching and habitat destruction. Photograph from San Diego Zoo.

Fully adult orangutan males have conspicuous cheek pads. Their voices can be heard miles away.

Polygyny and Sexual Dimorphism

from Lewin and Foley (2004) p. 173

Who Is Who Among the Primates ? •  •  •  • 

How Humans View Their Place in Nature Humans are Mammals, Specifically: Primates Abbreviated Taxonomy of the Primates Great Apes, Our Closest Non-human Relatives –  Orangutan (Pongo pygmaeus) –  Gorilla (Gorilla gorilla) –  Chimpanzee (Pan troglodytes) –  Bonobo (Pan paniscus) –  No model species for humans

•  Humans Are Special in Anatomy and Behavior •  Several Uniquely Human Traits Revolve Around Sexuality and Raising the Young

The gorilla (Gorilla gorilla) lives in the forests of Central Africa and West Africa, where it has been hunted to near-extinction. With males up to 400 pounds, gorillas are the largest primates. Photograph from Fort Worth Zoo.

Evengue-Gorillas, Loango National Park in Gabon (Central Africa). Silverback male in front. Photo taken by Rhett A. Butler

Who Is Who Among the Primates ? •  •  •  • 

How Humans View Their Place in Nature Humans are Mammals, Specifically: Primates Abbreviated Taxonomy of the Primates Great Apes, Our Closest Non-human Relatives –  Orangutan (Pongo pygmaeus) –  Gorilla (Gorilla gorilla) –  Chimpanzee (Pan troglodytes) –  Bonobo (Pan paniscus) –  No model species for humans

•  Humans Are Special in Anatomy and Behavior •  Several Uniquely Human Traits Revolve Around Sexuality and Raising the Young

The chimanzee (Pan troglodytes) lives in the rain forest of equatorial Africa. This photo (by Curt Busse) shows Mike, a member of the chimp community in Gombe/Tanzania studied extensively by Jane Goodall and coworkers.

Figan, alpha male of Gombe community, eating bushbuck leg. Photo: Curt Busse

Vulva of chimpanzee female in estrus Adult female chimpanzees show a conspicuous pink swelling of the anogenital region during estrus, that is, the time of ovulation and sexual receptivity. Estrus lasts for 10-15 days in a reproductive cycle of about 36 days.

Who Is Who Among the Primates ? •  •  •  • 

How Humans View Their Place in Nature Humans are Mammals, Specifically: Primates Abbreviated Taxonomy of the Primates Great Apes, Our Closest Non-human Relatives –  Orangutan (Pongo pygmaeus) –  Gorilla (Gorilla gorilla) –  Chimpanzee (Pan troglodytes) –  Bonobo (Pan paniscus) –  No model species for humans

•  Humans Are Special in Anatomy and Behavior •  Several Uniquely Human Traits Revolve Around Sexuality and Raising the Young

The bonobo (Pan paniscus) is a highly endangered species, limited in range to the Republic of Congo. Photo: Fort Worth Zoo.

Bonobos playing

Who Is Who Among the Primates ? •  •  •  • 

How Humans View Their Place in Nature Humans are Mammals, Specifically: Primates Abbreviated Taxonomy of the Primates Great Apes, Our Closest Non-human Relatives –  Orangutan (Pongo pygmaeus) –  Gorilla (Gorilla gorilla) –  Chimpanzee (Pan troglodytes) –  Bonobo (Pan paniscus) –  No model species for humans

•  Humans Are Special in Anatomy and Behavior •  Several Uniquely Human Traits Revolve Around Sexuality and Raising the Young

Who Is Who Among the Primates ? •  •  •  • 

How Humans View Their Place in Nature Humans are Mammals, Specifically: Primates Abbreviated Taxonomy of the Primates Great Apes, Our Closest Non-human Relatives –  Orangutan (Pongo pygmaeus) –  Gorilla (Gorilla gorilla) –  Chimpanzee (Pan troglodytes) –  Bonobo (Pan paniscus) –  No model species for humans

•  Humans Are Special in Anatomy and Behavior •  Several Uniquely Human Traits Revolve Around Sexuality and Raising the Young

Habitual Bipedalism of the Human:  Note differences in length of pelvis and in relative length of arms and legs.

From Lewin (1993)

Foot skeletons of Homo sapiens (top) Gorilla gorilla Cercopithecus (Old World monkey) Cebus (New World monkey) Notharctus (Eocence prosimian)

A)

B)

Figure 2.7: Opposable thumb allows different ways of manipulating tools. A. power grip (object grasped between fingers and palm while thumb applies counter pressure) B. precision grip (object held with tips of middle finger, index finger, and fully opposed thumb)

Brain size increased about threefold from Australopithecus afarensis (left) to Homo erectus (center) and Homo sapiens.

The first stone tools were made more than 2 million years ago by striking glancing blows with a hammer stone against the edge of a core stone. The resulting flakes had very sharp edges.

Cave painting by Cro-Magnon people in Lascaux (France), dated about 15,000 years ago.

Who Is Who Among the Primates ? •  •  •  • 

How Humans View Their Place in Nature Humans are Mammals, Specifically: Primates Abbreviated Taxonomy of the Primates Great Apes, Our Closest Non-human Relatives –  Orangutan (Pongo pygmaeus) –  Gorilla (Gorilla gorilla) –  Chimpanzee (Pan troglodytes) –  Bonobo (Pan paniscus) –  No model species for humans

•  Humans Are Special in Anatomy and Behavior •  Several Uniquely Human Traits Revolve Around Sexuality and Raising the Young

Problem: Paternity and Parental Investment •  •  •  •  • 

Animal species requiring large parental investment tend form pairs raising their offspring together Males gage parental investment to likelihood of paternity, which is eroded by extra-pair copulations Gibbon and gorilla families live in isolation Chimps and bonobos are promiscuous, and offspring are raised exclusively by their mothers Human children require enormous parental investment, but human families are embedded in large communities with many potential sex partners

Human Solution: Exclusive Sexual Bond •  Marriage, a covenant to raise common children together and to forego extramarital affairs •  Concealed estrus •  Long-lasting intercourse •  Permanent breasts as sexual attractants •  Modesty •  Interpretation: Together, these traits support a sexual bond between married partners. The bond’s exclusivity promotes male parental investment and reduces conflict from jealousy.

Who Is Who Among the Primates ? •  •  •  • 

How Humans View Their Place in Nature Humans are Mammals, Specifically: Primates Abbreviated Taxonomy of the Primates Great Apes, Our Closest Non-human Relatives –  Orangutan (Pongo pygmaeus) –  Gorilla (Gorilla gorilla) –  Chimpanzee (Pan troglodytes) –  Bonobo (Pan paniscus) –  No model species for humans

•  Humans Are Special in Anatomy and Behavior •  Several Uniquely Human Traits Revolve Around Sexuality and Raising the Young