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qid 4761 · history

Question: Homo habilis emerged around ________ years ago; Homo erectus followed at around _________ years ago.

  1. 1.8 million; 1.2 million
  2. 2.5 million; 1.8 million
  3. 1.4 million; 800,000
  4. 4.5 million; 3.2 million
  5. 2 million; 1.5 million
  6. 3 million; 2 million
  7. 4 million; 2.5 million
  8. 1.5 million; 1 million
  9. 3.6 million; 2.8 million
  10. 5 million; 3.5 million

Our answer: B. 2.5 million; 1.8 million Source quote machine-checked (exact quote)

A machine check confirms the quoted words appear at the source. A person has not yet reviewed these. EARN MARKS as a Human Reviewer

How it was answered

Multi-step solver (maze), replayed by code

card: maze · card sha256 a466585127beccd8…

Current source

Smithsonian National Museum of Natural History, Human Origins Program, "Homo habilis"

https://humanorigins.si.edu/evidence/human-fossils/species/homo-habilis

“When Lived: 2.4 million to 1.4 million years ago”

Source quote machine-checked (exact quote)

retrieved 2026-09-18T01:08:21.846Z

page text sha256 f6a6e53672a926bb… · content sha256 98a2963fb4c94ccb…

addendum maze_qid4761_b4_maze_input_ADDENDUM_source_rs20260918T010821Z · sha256 70bbe17e4cb20b53… · replaces the version below, addendum sha256 1a08fa3ec21aff87…

Earlier version (superseded)

https://humanorigins.si.edu/evidence/human-fossils/species/homo-habilis

Source weak (http_get_200_text_and_question_terms)

retrieved 2026-09-17T23:23:22.217Z

page text sha256 502c7d4a186f9e75… · content sha256 —

addendum maze_qid4761_b4_maze_input_ADDENDUM_source_bf20260917T232322Z · sha256 1a08fa3ec21aff87… · replaces the version below, addendum sha256 a2058eb80381db7c…

Earlier version (superseded)

No public source has been found for this card yet (3 places checked internally).

addendum maze_qid4761_b4_maze_input_ADDENDUM_source · sha256 a2058eb80381db7c…

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