How to Find Evolution’s Limit

Dice spiral

This is part of a series: How Fast is Evolution?
Next: Evolution’s Speed – My Assumptions and First Guesses

I might have figured out how to test for evolution’s limit in a lab.  In my previous series, I fixed a loophole in the definition of evolution’s limit.  In this series, I plan to learn whether my idea is practical.  I’ll list a bunch of info related to calculating how fast evolution must happen if it’s really how life appeared.  I hope to finish by calculating how big of a population I’d need to make my experiment work.

Here’s my idea:

Evolution is a game of chance.  It has rules – like the laws of physics, the current environment, and interaction with other creatures – and each mutation is a roll of the dice.  A good mutation is like rolling three 6’s in Risk – it’s very rare.  I want to cheat.

One rule of evolution is that it usually happens too slow to see.  If someone wants to study evolution – whether to test or confirm it – they must wait millions of years.  Since we humans don’t live that long, we have to speed up evolution to see it happen.  One way is to roll the dice very quickly – do mutation and natural selection to something with incredibly short generation times.  Another way is to roll a big bucket of dice all at once.

I already tried the first one.  Now I want to find if the second is practical.

Here’s how I’d do it:

  1. Get a big population of single-celled creatures
  2. Mutate all of them in one generation
  3. Turn off the mutator before the next generation
  4. Wait for natural selection to sort out the best mutants
  5. Repeat until I hit evolution’s limit

If I get a big enough population, then as long as:

  1. Life really appeared by abiogenesis + evolution,
  2. Evolution created genomes as big as the human genome (~3.5 billion base pairs), and
  3. It all took only 4.x billion years…

…I can pretty much guarantee that each round of this experiment will generate at least one good mutation, possibly more.  This would rig the game of evolution, turning it from a game of chance into an engineering machine.

To find if this is practical, I need to know how big of a population I need.  And right now, I don’t know.

Will it fit in a droplet?  A swimming pool?  A huge lake?

Here are some things I’ll need to learn before I can find if this experiment is practical:

  • What a typical mutation rate is
  • What a typical generation time is for single-celled creatures
  • All types of mutations
  • How common each type of mutation is
  • How common good mutations must be for evolution to make life in only 4 billion years
  • How many single-celled creatures will fit comfortably in a container

Based on what I know of genetics, it’s quite possible that this experiment wouldn’t be practical.  But if it is, and if nobody else has done it, I’d love to make it happen.  To actually do it, I’d have to get help from someone who knows a lot more about biology and genetics than I do.

This is part of a series: How Fast is Evolution?
Next: Evolution’s Speed – My Assumptions and First Guesses

Photo credit:

Advertisements

3 thoughts on “How to Find Evolution’s Limit

What do you think?

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s