Digital Fossil-Mining

Context: Squid Evolution Uncovered by Digital Fossil-Mining

A groundbreaking study from Japan, published in Science, has shed light on the evolutionary history of squids, which has long remained mysterious due to their soft bodies rarely fossilizing.

What is Digital Fossil-Mining?

• A non-invasive technique that involves:

  • Slowly grinding rocks layer by layer.

  • Taking high-resolution photographs at each level.

  • Stitching images together to form a 3D model of the rock’s interior.

• Helps detect and extract fragile or hidden fossils, such as squid beaks, without damaging the specimen.

                            

Key Discoveries:

• Researchers used carbonate concretions (from 110–70 million years ago, Cretaceous era) known for fossil preservation.

• They digitally reconstructed 263 squid beaks, previously only one such fossil was known.

• Found remains of at least 40 squid species across 23 genera and 5 families.

• Beaks belonged to both:

  • Oegopsida (deep-sea squids)

  • Myopsida (coastal squids)

Evolutionary Insights:

• Squids had diversified rapidly, with most modern families evolving within just 6 million years.

• They appeared 30 million years earlier than previously thought, flourishing by 100 million years ago.

• By the Late Cretaceous, squid fossils outnumbered ammonites and fish, indicating their ecological dominance.

• Squids were already replacing shelled cephalopods like ammonites and belemnites before the dinosaur extinction (~66 million years ago).

• Researchers suggest squids were pioneers of modern marine ecosystems, preceding fast, intelligent marine animals like dolphins and whales.