Topic: Biology

Scientists found signs of ancient life in rocks from Morocco's Dadès Valley. The discovery is surprising because it suggests that microbial communities existed in deep water millions of years ago.

In the Dadès Valley, Morocco, Dr. Rowan Martindale and her team were exploring ancient reef ecosystems that once existed beneath an ocean covering the region millions of years ago. To reach those ancient reefs, they had to cross extensive layers of rock known as turbidites.

Martindale noticed something unusual sitting on top of the ripples in these deposits. She called out to her colleague Stéphane Bodin and said, 'You need to get back here! These are wrinkle structures!' Wrinkle structures are small ridges and depressions that can form when microbial communities grow into mats across sandy sediment.

The team carefully investigated the rocks to confirm both the environment where the sediments formed and the biological origin of the unusual textures. They verified that the layers were indeed turbidites deposited in deep water, and then looked for chemical signatures that could reveal whether living organisms had played a role in creating the structures.

Their analysis showed elevated concentrations of carbon in the sediment layers directly beneath the wrinkles. Carbon enrichment is often associated with biological activity and provided an important clue that microbes were involved. The researchers then turned to modern oceans for answers, using video footage collected by remotely operated submersibles to study microbe communities.

Why It Matters

This discovery matters because it shows that microbial life can exist in deep water environments, which is important for understanding the evolution of life on Earth. It also highlights the importance of chemosynthetic microbes in ancient ecosystems.

Key Facts

• The team found wrinkle structures in rocks from Morocco's Dadès Valley that were formed millions of years ago.
• Wrinkle structures are usually fragile and often destroyed by animal activity before they can be preserved.
• The discovery suggests that microbial communities existed in deep water environments, which is surprising because sunlight cannot penetrate at those depths.
• Chemosynthetic microbes are known to form mats on turbidity deposits in modern oceans.

Key Terms

Turbidites

Layers of rock formed from underwater avalanches of mud, sand, and debris

Implications

This discovery matters because it shows that microbial life can exist in deep water environments, which is important for understanding the evolution of life on Earth. It also highlights the importance of chemosynthetic microbes in ancient ecosystems.