Big Trends in Human Evolution

Introduction – Human Evolution  Mosaic Evolution: ________________________  With respect to human evolution: _____________________ Developed at varying times along our evolutionary history

But how did we get here?  1.  2.  3.  4.  5.

Anatomical Adaptations for Bipedalism 1. ___________  Increase in ________  Changes to hallux  __________ 2. _______________  _____________________

Anatomical Adaptations for Bipedalism

3. _______________________  Increase in surface area  Extension ____________  __________ - angled towards the middle of the body

Anatomical Adaptations for Bipedalism 4. Pelvis  _____________________  ______________________

Anatomical Adaptations for Bipedalism 5. _________________  ____________________

Morphological Changes  6. Foramen Magnum – _______________________ Bipedal – ____________________ Quadrupedal – ______________________

Hominin Evolution

Pre-dating Australopithecus  Hominins discovered in _________________  Bipedal – debatable in some species  We will focus on the species for which there is ________________of bipedalism

Ardipithecus ramidus  Middle Awash area of Ethiopia  Approximately 4.4mya  Found:  1.  2.  3.

Ardipithecus ramidus  Indicators of Bipedalism  ____________________  Femur and pelvis  Humerus – _______________  Foot Phalanges ______________

Ardipithecus ramidus

 Ardi = “facultative” biped  What do you think this term mean?

Australopithecus afarensis  _______________  Hadar, Ethiopia  Laetoli, Tanzania  mya  Forest, woodland, grassland

A. afarensis – Traits Bipedal  1.  2. Some Arboreal Abilities Retained  1.  2.

A. afarensis – Traits

Type Fossil – “Lucy”  Found: 1974, Hadar, Ethiopia  ____________________  Both arms  Much of the pelvis  Left femur, right tibia  Hand and Foot bones  Adult (based on 3rd molar)  _____________

Type Site: Laetoli Footprints  Tanzania  3.6 mya  75 feet long preserved  _____________  ___________  ______________

A New Hominin  Australopithecus sediba  Discovered in 2008; located in South Africa  Proposed by some to be the best candidate __________ _________________

A New Hominin  Features:  _______________ _  Pelvis – ________ of Australopithecu s-like and Homo-like features  Hand –  Foot & ankle shape –

The Genus Homo – Overall Trends  Characterized by:

Introduction To Homo habilis  Contemporaneous with _______________________  Anatomically different than specimens assigned to the genus _______________________  Distinguishing feature – _________________  H. habilis shows an ___________________as compared to Australopithecines

Homo habilis – OH 24  Location: Olduvia Gorge  (Africa)  Comparison to Australopithecines:  1.  2. “Twiggy” or OH 24 Dated to ~ 1.8mya