ScienceStuff Why Do We Have Five Fingers?
Jul 30, 2025
Jacob Scott, a researcher at the University of Florida specializing in finger evolution, dives into why humans and many animals have five fingers. He discusses the evolutionary advantages that this configuration provides for dexterity and tool use. The podcast highlights fascinating transformations from early tetrapod ancestors and the reasons behind digit loss in species like horses and salamanders. Scott also unravels the genetic dynamics during embryonic development that govern finger formation, emphasizing the significance of maintaining five digits in humans.
AI Snips
Chapters
Transcript
Episode notes
Ancestors Had More Digits
- Our distant ancestor had six to eight digits on each limb, not just five.
- Our five-fingered hands evolved through a reduction from these more digit-rich ancestors.
Locomotion Drives Digit Loss
- Digit loss in evolution is often linked to locomotion, especially running.
- Fewer toes can make running on hard ground more efficient by concentrating weight on fewer points.
Spider Monkeys Lost Thumbs
- Spider monkeys lost their thumbs to better swing from vines.
- This shows evolution can reduce digits for functional advantages.