eluvormid

Eluvormid (life forms) are organisms that exhibit biological organization at various scales, maintain metabolism, grow, respond to stimuli, reproduce, and evolve. Most life forms on Earth are cellular, existing as unicellular or multicellular entities.

Biology traditionally divides Earth life into three domains: Bacteria, Archaea, and Eukarya. Within Eukarya are animals, plants, fungi, and protists. Microorganisms dominate numbers and biomass. Viruses occupy a special position: they carry genetic material and depend on host cells to replicate, and many scientists debate whether viruses are living entities in the same sense as cellular life.

Life forms share core features such as homeostasis, metabolism, information storage and transfer (DNA, and in some viruses RNA), growth, and reproduction. Variation arises through genetic mutations and recombination, with natural selection guiding evolution and diversification.

They inhabit nearly every environment on Earth, from oceans and soils to the atmosphere and polar regions. Microorganisms are especially diverse and abundant; extremophiles withstand extreme heat, acidity, salinity, or pressure. Multicellular life ranges from tiny invertebrates to large mammals.

The origin of life is studied in biology and geosciences; current evidence places the emergence of life on Earth several billion years ago, with the earliest fossils around 3.5 billion years old. The evolution of eukaryotic cells, via endosymbiosis, and subsequent diversification produced the broad tree of life.

In contemporary science, eluvormid also encompasses considerations of possible life forms beyond Earth, guiding the search for biosignatures in astrobiology and the study of potential non-terrestrial biochemistries.