Class Slides Set 15A Bipedalism Legs/Feet and Pelvis

Class Slides Set 15A

Bipedalism

Legs/Feet and Pelvis

Bipedalism

Legs/Feet and Pelvis

www.sciencedaily.com/releases/2008/05/080529140042.htm

www.guardian.co.uk/science/2008/jun/02/genetics.medicalresearch

http://www.sciam.com/article.cfm?chanID=sa003&articleID=0008EB7D-BC26-1138-BC2683414B7F0000

Arm swingingand

erect (bipedal)or

semi-erect walkingresulted in a number of

postcranial changes

Postcranial =

below the head(with bipeds)

behind the head(with quadrupeds)

Modern human

Postcrania

New World monkey

Understanding Physical Anthropology and Archaeology, 9th ed ., pp. 200, 429, 121

Apes

The ability to assume a fairly erect posture produced important

changes

Chimpanzee

The Primates, Time-Life (1974) p. 71

Bipedal Locomotion

Why bipedalism?

Understanding Physical Anthropology and Archaeology, 8th ed., p. 217

Possible Factors Influencing the

Initial Evolution of Bipedal Locomotion in Hominids.

Bipedalism

Bipedalism is related to tool use

Understanding Physical Anthropology and Archaeology, 8th ed., p. 217

Possible Factors Influencing the

Initial Evolution of Bipedal Locomotion in Hominids.

Humankind Emerging, 7th ed., p. 275

Positive Feedback Systems.

Acheulian biface (“hand axe”)

Understanding Physical Anthropology and Archaeology, 9th ed ., p. 239

Bipedalism

more about bipedalismand to tool use later

Bipedalism

Bipedalism also makes hunting

more energy efficient

Understanding Physical Anthropology and Archaeology, 8th ed., p. 217

Possible Factors Influencing the

Initial Evolution of Bipedal Locomotion in Hominids.

The Primates, Time-Life (1974) p. 44

Bipedalism

Seed and nut gatheringand

Feeding from bushes

Understanding Physical Anthropology and Archaeology, 8th ed., p. 217

Possible Factors Influencing the

Initial Evolution of Bipedal Locomotion in Hominids.

Bipedalism

Bipedalism and vision(visual surveillance)

Understanding Physical Anthropology and Archaeology, 8th ed., p. 217

Possible Factors Influencing the

Initial Evolution of Bipedal Locomotion in Hominids.

Humankind Emerging, 7th ed., p. 114

Eye Level and Sight.

Bipedalism

Bipedalism andLong-distance walking

Understanding Physical Anthropology and Archaeology, 8th ed., p. 217

Possible Factors Influencing the

Initial Evolution of Bipedal Locomotion in Hominids.

Bipedalism

Male help in

“provisioning”Owen Lovejoy “provisioning hypothesis”

Understanding Physical Anthropology and Archaeology, 8th ed., p. 217

Possible Factors Influencing the

Initial Evolution of Bipedal Locomotion in Hominids.

Humankind Emerging, 7th ed., p. 270

Pliocene Adaptations. (Lovejoy)

Bipedalism

Bipedalismand

other hominid traits

Understanding Physical Anthropology and Archaeology, 8th ed., p. 217

Possible Factors Influencing the

Initial Evolution of Bipedal Locomotion in Hominids.

Not on the chart

Bipedalism

body temperature

http://news.bbc.co.uk/sport1/hi/other_sports/1468591.stm

http://www.sunspot.net/sports/baseball/bal-te.sp.orioles18feb18,0,360173.story?coll=bal-utility-baseball

Bipedalism

R. Falk (1989) suggested that bipedalism resulted in the development of a cooling mechanism for the brain.

CA 31:2:187

Humankind Emerging, 7th ed., p. 268

Body Surface and Solar Radiation.

Understanding Physical Anthropology and Archaeology, 8th ed., p. 217

Possible Factors Influencing the

Initial Evolution of Bipedal Locomotion in Hominids.

Not on the chart

Bipedalism

may have beenan arboreal forest

adaptation

Video: Search for the First Human --

A Secrets of the Dead SpecialWeek 07

Understanding Physical Anthropology and Archaeology, 8th ed., p. 217

Possible Factors Influencing the

Initial Evolution of Bipedal Locomotion in Hominids.

Not on the chart

Bipedal walkingresulted in a number of

postcranial changes in the legs and feet . . .

The legs and feet . . .

feet become more foot-like

gibbons

bonobos chimps

gorillashumans

Campbell and Loy, Humankind Emerging, 8th ed, p. 138f

orangutans

orangutansgibbons bonobos chimps gorillas humans

Foot (pedal) anatomy.

Understanding Physical Anthropology and Archaeology, 9th ed ., p. 435

Humankind Emerging, 7th ed., p. 383

Grover Krantz.

Foot (pedal) anatomy.

Understanding Physical Anthropology and Archaeology, 9th ed., p. 436

Leg bones are much stouterand

have more pronounceddorsal ridges

(on the back)

Leg muscle structures change

Understanding Physical Anthropology and Archaeology, 8th ed., p. 224

Comparison of muscles that act to extend the hip.

Humans have developed a “closed-knee stance”

Humankind Emerging, 7th ed., p. 193

Closed-Knee Stance.

WT 15000 from Nariokotome, Kenya:

the most complete Homo erectus specimen yet found

Understanding Physical Anthropology and Archaeology, 9th ed ., p. 235

Humankind Emerging, 7th ed., p. 242

There is a lossof some mobility

and “prehensility”

in feet

Prehensility = the ability to grasp

White-handed gibbon

Understanding Physical Anthropology and Archaeology, 9th ed ., p. 131

A number of changes take place in the pelvis

. . .

• becomes shorter and wider . . .

• has a “distinct pelvic bowl” . . .

• and the muscle attachment ridges become heavier . . .

The Pelvis

• becomes shorter and wider . . .

• has a “distinct pelvic bowl” . . .

• and the muscle attachment ridges become heavier . . .

The Pelvis

Ossa coxae. (a) Homo sapiens.

(b) Australopithecus. (c) Chimpanzee

xx

Understanding Physical Anthropology and Archaeology, 9th ed ., p. 199

Pelvic girdles.

Understanding Physical Anthropology and Archaeology, 9th ed ., p. 435

• becomes shorter and wider . . .

• has a “distinct pelvic bowl” . . .

• and the muscle attachment ridges become heavier . . .

The Pelvis

Pelvic girdles.

Understanding Physical Anthropology and Archaeology, 9th ed ., p. 435

And the muscle attachment ridges one

the pelvis become heavier . . .

Ossa coxae. (a) Homo sapiens.

(b) Australopithecus. (c) Chimpanzee

xx

Understanding Physical Anthropology and Archaeology, 9th ed ., p. 199

The human os coxae, composed of three bones. (R)

Understanding Physical Anthropology and Archaeology, 9th ed ., p. 199

More on pelvic changes later, with the discussion of

Australopithecus(“southern ape”)

External tails are lost

Skeleton of a brachiator (gibbon)

Understanding Physical Anthropology and Archaeology, 9th ed ., p. 121

Continue on to Set #15B

The Upper Body

Modern human skeleton

Understanding Physical Anthropology and Archaeology, 8th ed., p. 223