Cúrum

Cúrum is a fictional species featured in the science fiction novel "The Expanse" series by James S. A. Corey. They are an ancient, silicon-based lifeform native to the planet Ilus, also known as the planet "Eden" by humans. Cúrum are characterized by their slow metabolism, immense lifespan, and a deep connection to the planet's geological and biological systems.

Physically, cúrum are described as large, amorphous beings that resemble crystalline rock formations. They possess a unique physiology that allows them to absorb nutrients directly from minerals and to communicate through subtle vibrations and electrical signals. Their life cycle is extremely protracted, with individuals potentially living for millennia. They have a hive-mind like consciousness, with individual cúrum acting as extensions of a larger collective intelligence.

The cúrum are not technologically advanced in the human sense. Instead, their "technology" is biological and geological, integrated into the very fabric of Ilus. They are responsible for creating the planet's complex ecosystem and its advanced, self-regulating nanotechnological systems, which humans later discover and attempt to exploit. Their primary motivation appears to be the preservation and continuation of life on Ilus, viewing any external interference as a threat. Their interactions with humans are often characterized by a lack of direct conflict, but rather by passive resistance and the manipulation of their environment to deter or incapacitate intruders. The cúrum represent a profound challenge to humanity's understanding of life and intelligence.