Red Ice News

The Future is the Past

Mars Announcement Raises Question: What Is Life?
New to Red Ice? Start Here!

Mars Announcement Raises Question: What Is Life?

Source: space.com
NASA officials announced March 12 that ancient Mars could have supported primitive life. But this begs the question: What exactly constitutes life?

Merriam-Webster.com defines life as "an organismic state characterized by capacity for metabolism, growth, reaction to stimuli and reproduction." But there’s no single satisfactory definition of life.

"I think it is a mistake to try to define life, because we have only one example of life, familiar life on Earth, and we have reason to believe that this example may be unrepresentative of life in general," Carol Cleland, a philosopher of science at the University of Colorado, Boulder, told LiveScience in an email.

Defining life

Aristotle made the first attempt at a definition, describing life as something that grows, maintains itself and reproduces. But this definition would exclude mules, which are sterile, while including things like fire.

Calling life something that has a metabolism, the ability to take in energy to grow or move and excrete waste, is no good either; cars do this, for example.

In 1944, the physicist Erwin Schrödinger gave life a definition based on the second law of thermodynamics, which states that the entropy, or disorder, of a closed system increases over time. Schrödinger defined life as something that decreases or maintains its entropy. Yet this definition fails because it includes crystals, which resist entropy by forming highly structured lattices.

Trying to define life by its qualities is the wrong approach, Cleland said. As an example, she cites scientists’ early attempts to define water in terms of properties like being wet, transparent and a good solvent. "We didn’t ’define’ water as H2O, but rather discovered, in the context of molecular theory, that it is a chemical substance composed mostly of H2O molecules," Cleland said.

Life on Earth is typically divided into two main groups: the cellular life forms, which include archaea, bacteria and eukarya (all the plants and animals), and non-cellular life forms, like viruses. Whether viruses, which can replicate only inside the cells of a host organism, count as "life" is debated.

[...]

Read the full article at: space.com

Comments

We're Hiring

We are looking for a professional video editor, animator and graphics expert that can join us full time to work on our video productions.

Apply

Help Out

Sign up for a membership to support Red Ice. If you want to help advance our efforts further, please:

Donate

Tips

Send us a news tip or a
Guest suggestion

Send Tip

Related News

NASA Confirms Signs of Water Flowing on Mars, Possible Niches for Life
NASA Confirms Signs of Water Flowing on Mars, Possible Niches for Life
Martian meteorite yields more evidence of the possibility of life on Mars
Martian meteorite yields more evidence of the possibility of life on Mars

Archives Pick

Red Ice T-Shirts

Red Ice Radio

3Fourteen

Con Inc., J6 Political Prisoners & The Pedophile Problem
Kim Coulter - Con Inc., J6 Political Prisoners & The Pedophile Problem
Why European Culture, Art and Beauty Matter
Gifts - Why European Culture, Art and Beauty Matter

TV

Laughter: The New Weapon Of The Far-Right
Laughter: The New Weapon Of The Far-Right
London’s Fourth Plinth To Get Fat Black “Everywoman” Statue
London’s Fourth Plinth To Get Fat Black “Everywoman” Statue

RSSYoutubeGoogle+iTunesSoundCloudStitcherTuneIn

Design by Henrik Palmgren © Red Ice Privacy Policy