Life

Welcome to the portal for Life. We hope to cover this topic, a quite large and broad one -- with a contentious definition at that, from a science-fictional and speculative perspective for authors and readers.

...Life is the characteristic that distinguishes organisms from inorganic substances and dead objects. ... Wikipedia:Life_(disambiguation)

... An organism ... is any living thing that functions as an individual.

Many criteria, few of them widely accepted, have been proposed to define what is an organism. Among the commonest is that an organism has autonomous reproduction, growth, and metabolism. This would exclude viruses, despite that fact that they evolve like organisms. Other problematic cases include colonial organisms... Wikipedia:Organism

These colonial organisms include eusocial insects, corals and other reef-builders, siphonophores and so many more. Eusocial insects exhibit caste systems, a division of labor and specialization in tasks among different members of the same colony -- which is just like the different specialized functions of cells in an animal's body.

Further, siphonophores push the boundaries of common sense: although they resemble jellyfish and appear to be complete organisms, they are in actuality made of zooids, which exhibit far more autonomy than the typical animal cell. At what point does a multicellular organism become a colony? At what point does a colony become the other? Indeed, back when we were just microscopic organisms -- our ancestors, we may have gone through a colony phase on our way from solitary single cells, to multicellularity.

Life is a quality that distinguishes matter that has biological processes, such as signaling and self-sustaining processes, from matter that does not, and is defined descriptively by the capacity for homeostasis, organisation, metabolism, growth, adaptation, response to stimuli, and reproduction...

- Excerpt from Wikipedia:Life

STUB - go to Category:Life for now