Updated
Updated · The New York Times · Jul 9
Spriggina Fossils Show 500-Million-Year-Old Right-Handedness in Animals
Updated
Updated · The New York Times · Jul 9

Spriggina Fossils Show 500-Million-Year-Old Right-Handedness in Animals

3 articles · Updated · The New York Times · Jul 9

Summary

  • South Australian Spriggina fossils suggest animals were showing behavioral handedness more than 500 million years ago, making the thumb-size organism the earliest known example yet identified.
  • Researchers found many specimens bent in the same direction, indicating Spriggina consistently turned right as it moved along the seafloor despite having no limbs.
  • The study, published Thursday in Scientific Reports, argues that once complex life evolved distinct left and right sides, side preference could emerge as well.
  • That pushes evidence of handedness far beyond the previous fossil record, which included a right-handed Homo habilis from 1.8 million years ago and right-veering trilobites.

Insights

Could the ancient rightward bias in Spriggina fossils reveal a universal principle of lateralization in life's evolution?
Is it possible that what looks like behavioral handedness in Spriggina fossils is actually a result of fossilization or geological forces?