Martian Antarctica meteorite has evidence of life!

no. prions propagate. according to the theory in the SciAm article, nanobacteria aren't really bacteria. they're nonliving. they don't replicate or propagate. they just fall into patterns like crystals do.

people used to think they were living but the article says the authors took a closer look and that nanobacteria aren't living. maybe they'll win, maybe not.

i was going to say "prions replicate", but wikipedia says not.

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http://en.wikipedia.org/wiki/Prion

A prion (pronounced /ˈpriː.ɒn/ ( listen)[1]) is an infectious agent that is composed primarily of protein. To date, all such agents that have been discovered propagate by transmitting a mis-folded protein state; the protein itself does not self-replicate and the process is dependent on the presence of the polypeptide in the host organism.[2] The mis-folded form of the prion protein has been implicated in a number of diseases in a variety of mammals, including bovine spongiform encephalopathy (BSE, also known as "mad cow disease"😉 in cattle and Creutzfeldt–Jakob disease (CJD) in humans. All known prion diseases affect the structure of the brain or other neural tissue, and all are currently untreatable and are always fatal.[3] In general usage, prion refers to the theoretical unit of infection. In scientific notation, PrPC refers to the endogenous form of prion protein (PrP), which is found in a multitude of tissues, while PrPSc refers to the misfolded form of PrP, that is responsible for the formation of amyloid plaques and neurodegeneration.

http://en.wikipedia.org/wiki/Nanobacteria

Nanobacteria is the name of a proposed class of living organisms; specifically cell-walled microorganisms with a size much smaller than the generally accepted lower limit size for life (about 200 nanometres for bacteria). Originally based on observed nano-scale structures in geological formations (including some meteorites), the status of nanobacteria is controversial: some researchers suggest they are a new class of living organisms [1][2] capable of incorporating radiolabeled uridine,[3] while other investigators attribute to them a simpler, abiotic nature.[4][5]

The term calcifying nanoparticles (CNPs) has also been used as a conservative name regarding their possible status as a life form. The most recent research tends to agree that these structures exist, and probably replicate in some way, but their status as living entities is still hotly debated. In medicine, they have been implicated in the formation of both kidney stones and arterial plaque.