So that's where they've been hiding. An entirely new group of organisms discovered at the bottom of the Arctic Ocean are our closest simple-celled relatives ever found. Approximately 2 billion years ago, complex eukaryotic cells, which make up animals, plants and fungi, split from smaller, simpler cells called prokaryotes. Researchers have now identified our closest relatives from before this split. Thijs Ettema at Uppsala University, Sweden, and his team discovered the new organisms when they analysed DNA extracted from underwater sediment near Loki's Castle, a region of hydrothermal vents along the Arctic mid-ocean ridge(Nature,DOI:10.1038ature14447). Named Lokiarchaea, the organisms are a new type of archaea. Like fellow prokaryotic bacteria, archaea lack a true cell nucleus and other complex cell machinery. But intriguingly, the Lokiarchaea appear to have more than 100 genes coding for sophisticated cellular functions such as deforming cell membranes and forming and transporting bubble-like vesicles around the cell - functions that are usually only seen in eukaryotes like us.
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