So why does

an understanding

of what an evolutionary agent is

help us

understand the origin of life,

and in particular

the multiple origins of life.

And it's worth starting

with a case study here

This is Sol Spiegelman

and he was a virologist

and he was interested in the evolution

of very simple viruses.

And the virus he worked with

was called Q Beta Phage.

And this is a very small RNA virus.

And he asked the following question:

What is the minimum genome

the Q Beta has to possess

in order to successfully complete

its life cycle?

But he tricked the virus.

He put a population of viruses

in a test tube,

along with enzymes

that normally

it would have to encode itself.

But he ensured that those enzymes

were always present.

And what he observed,

over multiple replication rounds

of the virus

in this new environment that he created,

was that the virus became

smaller and smaller and smaller,

until it eliminated

all the traces

of the enzyme that now existed

with certainty

in the environment

in which it was evolving.

So we can interpret this experiment

in the following way:

here's a Venn diagram

in one set

of the viral genome V

and another set, the environment,

H, the host.

And the intersection of these two sets,

a gene shared

by the virus and the host

or the virus and its environment,

and what Spiegelman discovered

is that if you make

the environment certain,

then,

the virus minimizes itself.

It throws away all genes it doesn't need

because they're already there.

This is minimalogy.

But he could have performed

an alternative experiment,

and made the environment

very uncertain.

And when environments are very uncertain,

that is, you can't throw things away

because you know they won't be there,

then you have to encode them

intrinsically.

So a good example for us

are vitamins.

With respect to vitamins,

we're minimal,

because we know

they're always there,

we don't have to synthesize them,

right,

but many other genes we can't

be certain we can acquire

from the environment,

so we have to encode them

and transmit them ourselves.

And we call that autonomy.

So these are two different configurations

for an adaptive agent.

Now, many people would call

a virus "non-living"

because it depends on its host

to replicate,

but of course,

we depend on the environment to replicate,

too, because we need vitamins.

So really there is a spectrum

of adaptive agency.

On the one hand,

there are organisms that live

in very certain environments.

And they become simple.

There are other organisms

that live in very uncertain environments,

and they become complex.

They encode more and more

in their genes.

And life spans

this informational spectrum,

from organisms

that encode very little about the world

because they don't need to,

to organisms that encode a great deal

about the world,

because they need to,

to complete their life cycle.

And when you think about it

it in this information theory term,

the way an organism,

or life,

or an agent really is,

is a mechanism

for acquiring adaptive information

about the world that it

propagates forward in time,

then computer viruses,

the block chain,

the Constitution,

and many, many other cultural forms,

are essentially living.

There's nothing special

about

the biochemical example,

a replicated cell,

because a replicating cell

is simply a

somewhat autonomous

informational entity that is

able to propagate itself

forward in time,

just like a Constitution

can.

But like a virus,

the Constitution requires us.

We are

the vitamins

of the Constitution.

And this leads to a very open question

that's worth debating.

On one hand,

we could be fundamentalist.

We could say look,

all of life depends on chemistry,

and so finding the simplest chemistry

that is capable of encoding

adaptive information about the world

is where life really started.

But another possibility say,

well not really, because at any scale

that you can find this basic

set of mechanisms,

you're entitled to call it life.

And you're even

entitled to call it an independent

origin of life.

So by analogy,

someone might say,

"To understand architecture,

to understand Gothic and Renaissance,

or Baroque,

or Rococo architecture,

you need understand quantum mechanics."

And I think that would be foolish,

because all of them of course

ultimately depend on quantum mechanics,

but it's not the differences

in the physics

that explain

the differences in the architecture.

That requires a higher level

of understanding.

And so the pluralist approach

to the multiple origin of life

says that every level,

we need to find those unique mechanisms

that can support

propagation of information.

And there isn't

a "correct,"

most basic level.

It depends on

the question that you're asking

and the variation

that you're trying to explain.