User blog:Mr.Robbo/Human Chauvinism 4

Human Chauvinism

Human Chauvinism 2

Human Chauvinism 3

Let's see what other human characteristics could be just that, purely human characteristics...

DNA
I'm sure anybody who's read or watched Jurassic Park knows that DNA, or deoxyribonucleaic acid if you want to sound spiffy, is used to encode the genetic information of just about all life on Earth, and no wonder; it's generally thought that every species on Earth relates back to a single primordial species from which all others stemmed from - LUCA (Last Universal Common Ancestor). I'm sure you can imagine my concern when I viewed a Ben 10 advert this morning which unimaginatively assumes that apparently all aliens just happen to posess DNA!

Admittedly, DNA is an excellent carrier for genetic information, and some sort of 'panspermia' origin of life (most life in the galaxy has a single common origin) could explain the DNA thing, but come on! Is that the best people can do?! Bah! What is DNA, anyway? Put simply, DNA is basically chains of proteins (or amino acids, which make up proteins anyway; I'm no biologist) that encode genetic information, but why just proteins? Cellulose is more complex than DNA, lipids could be a viable replacement for proteins at low temperatures and fluorocarbons and fluorosilicones viable replacements for high temperatures. I'm sure people could come up with plenty of other ideas. I mean, you could even just use a variation of DNA with different chemical makeup for the proteins not seen on Earth, such as with right-handed, instead of left-handed amino acids.

Carbon-based Life
Carbon is wonderful for life. When unionised, it has four electrons in its outer shell. Four! That means it can form chemical bonds with four other atoms! You can make structural chains and sheets of these particles and still have bonds left over for attatching various organic chemicals. No wonder it's so handy for creating complex life! The makers of Doctor Who had a good go at calcium-based life with their Raxacoricofallapatorians (Slitheen), but calcium is a false hope. It has a mere two outer-shell electrons, meaning all you could really make is random chains of clacium with nothing attached. Is there any hope for non-carbon-based life?

Well, Star Trek will tell you that the party starts with silicon. An excellent choice! Silicon is just below carbon in the periodic table, which means it's almost just like carbon, but bigger. Unfortunately, chains of silicon make unstable salines; what you need to do is throw in some oxygen to make something similar to fluorosilicones, which are much more stable and make up something similar to alternating chains of silicon and oxygen. There are plenty of other candidates, too; boron is just like carbon, but has to struggle along with just three outer electrons. Phosphorus has a massive five outer electrons, but is pretty rare.

By the way, it's been speculated that silicon-based life would 'breathe out' silicon dioxide (sand), which is weird, but original.

Water as a Solvent
Right! First, let's get some things straight! We are carbon-based life. We use water as a solvent. There may also be boron-based life, silicon-based life and phosphorus-based life. There may also be life that uses methane, ammonia or even sulfur as a solvent. It's not as simple as 'this is water-based life' or 'this is ammonia-based life'! It isn't the same thing! Life may be based on some sort of element in its chemical structures, but what it dissolves these chemical structures in is a different thing entirely! This is what I'm talking about now. Solvents, not elements.

You have to be careful when you're choosing a solvent to base life on. For example, you could not have protein-life or carbon-based life that uses sulfur as a solvent, as molten sulfur is at hundreds of degrees Celcius, and would quickly break down these proteins. There are also much more obscure things to consider, such as the fact that protein-life also couldn't use liquid methane as a solvent, as proteins are polar substances, while methane makes a non-polar liquid, meaning proteins couldn't dissolve in them. You'd have to use something like lipids instead.

Some argue that water is a superior solvent for life because it has many interesting properties, such as the fact that it freezes from the top down, so any prehistoric sea creatures will be able to survive cold climatic or seasonal shifts under the insulative protection of a layer of ice. A solvent that froze from the bottom up would block access to the floors of bodies of water, trapping life in a top layer and exposing them more to the elements. It would be interesting to see what characteristics would be evolved as a result of this...