Why in news?
Scientists recently completed a large genetic and morphological review of sea‑floor life, revealing 57 new species of foraminifera. These tiny shelled organisms have long been used by geologists to reconstruct past climates. The discovery emphasises that much marine diversity remains undocumented.
Background
Foraminifera are single‑celled protists that live in the world’s oceans. They build shells, called tests, from calcium carbonate or agglutinated sand grains. When the organisms die, their shells sink to the sea floor and accumulate in sediments. Because their shapes and chemical composition vary with temperature and salinity, fossil foraminifera help scientists infer ocean temperatures, sea‑level changes and pollution over millions of years. About 9,000 species are alive today, while fossil records document more than 40,000 extinct species.
Key characteristics
- Tiny size: Most species measure only 0.1–1 mm across. Despite their small size, they have intricate chambers and openings through which they extend thread‑like pseudopods to capture food.
- Diverse habitats: Some foraminifera float in the open ocean (planktonic), while others live on or within sea‑floor sediment (benthic). The new study found many previously unknown species in the Southern Hemisphere.
- Environmental indicators: Different species tolerate particular temperature ranges, salinity and oxygen levels. Their presence in sediment cores serves as a proxy for past climates and pollution events.
- Historical record: Because their shells preserve well, foraminifera form a continuous fossil record through geological time. They were crucial in developing the geologic time scale and continue to aid oil and gas exploration.
Significance of the new discoveries
- Expanding biodiversity knowledge: Documenting new species provides a more complete picture of marine life and can improve our understanding of evolutionary relationships.
- Refining climate models: Accurate species identification allows researchers to better interpret fossil assemblages and reconstruct past ocean conditions, enhancing predictions of future climate change.
- Conservation implications: Some foraminifera live in sensitive habitats such as coral reefs and seagrass beds. Recognising their diversity can inform conservation strategies for these ecosystems.
Conclusion
The discovery of dozens of new foraminifera species reminds us that even common organisms hold surprises. These minute architects of the ocean floor have recorded Earth’s environmental history for millions of years. Continuing research will not only reveal more species but also sharpen our tools for reading their climate messages.
Source: Phys.org · British Geological Survey