On Humans Where Did Humans Evolve? Gazing at the Changing Nature of the Garden of Eden ~ Denise Su
Mar 7, 2026
Denise Su, a paleoecologist who reconstructs ancient environments, explores where humans evolved. She examines early hominins, foot anatomy and arboreal habits. She explains how isotopes, fauna and soils reveal diets and habitats. She unpacks climate-driven forest loss, the range of savannas, adaptability and the rise of Homo erectus with long-distance walking and thermoregulation.
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Hominin Origins Combined Tree Use And Bipedalism
- Our hominin lineage began in Africa about 6–7 million years ago and early members like Ardipithecus retained tree-climbing anatomy while showing some bipedal traits.
- Ardipithecus had an opposable big toe and long curved fingers indicating significant arboreal activity despite walking bipedally on the ground.
Lucy Shows Bipedalism Plus Dietary Shift
- Australopithecus afarensis (Lucy) shows habitual bipedality with feet losing an opposable big toe but still retaining curved toes, indicating partial arboreal ancestry.
- Tooth isotope (C3/C4) data reveal dietary shifts: Ardipithecus ate mainly C3 (trees), while A. afarensis incorporated C4 (grassland) foods.
Reconstructing Ancient Landscapes Is A Multi‑Stranded Puzzle
- Paleoecology reconstructs past environments by combining faunal lists, soil chemistry, and microscopic plant silica (phytoliths) rather than relying on a single line of evidence.
- Denise Su compares this work to assembling a scattered, incomplete puzzle without a reference picture.