10.3 Major trends in hominin evoloution

What is cultural evolution in hominins?

The development of complex languages and the ability to speak, which allowed us to communicate, share stories, ideas, rituals, and new technologies.

What is bipedal locomotion?

Walking erect in a sustained fashion on hind legs, which structurally results in an S-shaped spine and a centralized foramen magnum.

What structural changes occurred in limb structures during the transition to land?

A shift from an arboreal life in treetops to walking on land, changing the femur shape to allow for bipedalism, altering the shape of the feet, and increasing the length of the legs.

What are the overarching physical trends observed in hominin evolution?

An increased size in cranium, height, and width of the brain, increased length of feet/legs and arms, a reduction in tooth size, and a more central foramen magnum.

What primary structural trend distinguishes members of the genus Homo from Australopithecus?

An increased brain capacity along with the significantly greater cognitive capabilities it provides.

What specific trends occurred regarding hominin skull shape?

The forehead shape shifted from sloping to flat, brain/cranium size increased, zygomatic arch size decreased, the brow ridge went from present to absent, and the foramen magnum moved from the back of the skull to the center.

What specific trends occurred regarding hominin pelvic shape?

pelvic size reduced, the heel bone increased in size, the pelvis became must more narrower

What specific trends occurred regarding hominin jaw size?

The jaw bone changed from thick to thin, teeth size decreased, and the jaw shape changed from U-shaped to V-shaped (parabolic).

What is the zygomatic arch?

Zygomatic arch is a bony bridge on the side of your skull that connects to the jaw muscle