Australopithecus garhi and Kenyanthopus platyops

Australopithecus garhi

  • Found in the Middle Awash region of Ethiopia.
  • Dated to 2.5 mya (million years ago), which is younger than Au. afarensis.
  • Fills a temporal gap between hominin finds in the region.
  • Anatomical Differences:
    • Relatively large cranial capacity of 450 cc.
    • Larger hind dentition than other gracile Australopithecines.
    • Longer hind limbs than Au. afarensis, but still capable of arboreal movement.
  • Fossil Record:
    • Not well-documented and based on limited fossil specimens.
  • Tool Use:
    • Crude stone tools resembling Oldowan tools found in association with Au. garhi.
    • These tools are among the earliest technologies found with a hominin.

Kenyanthopus platyops

  • Discovery:
    • A specimen (KNM-WT 40000) from Lake Turkana in Kenya.
    • Discovered by Maeve Leakey in 1999.
    • The name "platyops" refers to its flatter-faced appearance.
  • Dating:
    • Dated to between 3.5 mya and 3.2 mya.
  • Taxonomic Debate:
    • Some suggest it is an Australopithecus, possibly even Au. afarensis (with a seemingly small brain size).
    • Others place it in Homo due to small dentition and a flat, orthognathic face.
  • Arguments for Homo Ancestry:
    • Discoverers argue this species is ancestral to Homo, particularly Homo ruldolfensis.
  • Tool Association:
    • Researchers have linked the earliest tool finds from Lomekwi, Kenya (dated to 3.3 mya) to this specimen due to close geographic proximity.