KERNEL: Evolution

KERNEL: Evolution
CONTENTS: Replicators (fecundity, fidelity, longevity), natural selection, genotype, phenotype, extended phenotype, ecosystems


The theory of evolution is somewhat tricky, as it has itself evolved over time. While there is broad scientific consensus, even such fundamentals as what should be considered the 'unit of selection' are hotly contested.

I personally favor the 'gene' (functionally defined in Richard Dawkins' The Selfish Gene) as the unit of selection, with the operative concept being 'that which replicates'. In that sense, genetics can be alluded to without going into detail. He defines 'general' natural selection as the differential survival of entities.

At any rate, it seems  as good a starting point for future scientists as any, from which they may draw their own conclusions.

I would personally like to include Dawkin's concept of the Extended Phenotype... the idea that genes encode not only the organism (phenotype), but also many alterations of the environment via the organism's behaviors ('extended' phenotype).

Formulation

As many more individuals are produced than can possibly survive, there must in every case be a struggle for existence, either one individual with another of the same species, or with the individuals of distinct species, or with the physical conditions of life.… 

Can it, then, be thought improbable, seeing that variations useful to man have undoubtedly occurred, that other variations useful in some way to each being in the great and complex battle of life, should sometimes occur in the course of thousands of generations?  

If such do occur, can we doubt (remembering that many more individuals are born than can possibly survive) that individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind?  

On the other hand, we may feel sure that any variation in the least degree injurious would be rigidly destroyed.  

This preservation of favourable variations and the rejection of injurious variations, I call Natural Selection.

-- From The Origin of Species by Charles Darwin


Reformulation

1. Traits: Organisms pass (genetic) traits on to their offspring (sometimes imperfectly).
2. Variation: There is trait/organism variation in every population.
3. Offspring: Organisms produce more offspring than can survive.
4. Competition: Organisms compete for limited resources (according to their traits).
5. Natural Selection: Those organisms embodying more beneficial (adaptive) traits are more likely to survive and reproduce (differential survival of entities).

To which I'd add:

1. Speciation: the Origin of Species.
2. The Extended Phenotype (Dawkins): Genotype > Phenotype > Environment > Genotype
3. You Are Here: Note on where one fits in the Grand Scheme of Things

Poetic Rendition

The Way of Life

1. The First Ancestor 

In the deeps of time

In the seethe of chaos

In the broth of possibility

The first ancestor chanced to be 

Matter twined unto itself 

Itself the pattern for another 

A doing undone

To do again  

One became two 

Two became four 

Four became many 

Many became all 

In the deep of time 

They came to build bodies 

Not to be but to do 

Shaped by the world 

Shaping the world in turn 

Built to the pattern 

To protect the pattern 

To carry the pattern 

Forward in space 

Forward in time 

Life of the body short 

Life of the pattern long 

 

Spread high and low 

Deep and wide and long 

Filling all the world 

One great family of life

2. Pattern

Pattern lies within all life
Too small for eyes to see
Encoded with instructions
Pattern carried forward
Through trial and time

According to pattern
Bodies and their parts
Are built to plan

According to pattern
Bodies and their workings
Are regulated in function

According to pattern
Bodies in their features
Are constrained in possibility

According to pattern
Bodies in their behaviors
Are given tendencies

These expressions we call traits

Pattern is copied from parents
Half from each
Passed to offspring
According to rules passed down
Within the pattern itself

Cut in sex in snippets
Shuffled and reordered
Its combinations enduring
Yet ever changing

Pattern may be copied awry
And the pattern is changed

Pattern may be damaged
And the pattern is changed

Pattern may be rewritten
And the pattern is changed

Where the pattern is changed
Are bodies changed

We call these changes mutation

Mutation in pattern
Mutation in form
Mutation in function
Mutation in behavior

Often is change injurious
Sometimes is change indifferent
Seldom is change advantageous

Advantage is rare
Advantage is precious
Advantage is preserved
Advantage is compounded
Refined in the long course of generations

From the first pattern
Of the first ancestor
Is the pattern rewritten

Mutation writ slow
Adaptation writ quick

Pattern may lie long 

Beyond your grasp of knowing
Yet knowing that pattern is
May guide your knowing

3. Selection

More are brought forth
Than the world can bear

Not all who are born survive
Not all who survive may breed
Not all who breed give birth
Nor bring their young to breed again
Passing pattern from parent to offspring
According to what is written

In this spiral of life
Only a few go forward
Of the many who live

Without intent
Without malice
Without mercy
The world weighs upon all

Life contends for life

Each with its kind
Each with other kinds
Each vies with the world
Each vies for scarce resource
Each exposed to hard chance
Each according to its pattern

Through quick adaptation
Through slow mutation
The better adapted may prosper
The worse adapted fade

Thus, unknowing and blind
The world selects
Which shall flourish
Which shall fail

4. Evolution

Thus the world sifts pattern

That prospers which preserves pattern

That prospers which is fecund

That prospers which endures

That withers which is less of these

Even unto extinction

Advantage passes forward

Hindrance is culled

Winnowed by what is

Winnowed by what is not

So is the unpatterned patterned

Accident honed to fine edge

The simple made complex

Form fit to function

In an ever changing world

5. Many Kinds

Whence come the many kinds?

Each kind is as a branch of the great tree

When one kind is parted for a while
Some of their number here
Some of their number there
Separated
By land or sea
By diet or habit

Each grows in its surrounds
Each shaped by its surrounds
Each cut off from the other

Through many generations
Patterns diverge according to need
Bodies diverge according to pattern
Each adapts to its surrounds
Each accumulates small changes of pattern

As small difference grows
Fertile offspring fail
A branch is parted
Two kinds where once was one

Kinds from kind are sprung
In the long years of deep time
So many branches
So many kinds

6. Life in the World

The world shapes life
Life builds bodies
Bodies bring behavior
Life shapes the world

The changed world

Shapes life anew

Pattern in the one shapes
Pattern of the other

Look around you
See the teeming life
See its mark upon the world

See the worlds mark upon life

See the balance
See what disturbs it
See how it heals

See your place within it

7.  You

You are a living entity

You are of the family of life

You are not special

You are special

You and yours are not among

 The many gone extinct

Reached the end of their run

Of well adapted fortune

Each of your ancestors

Survived long enough to reproduce

Reaching back to the first

You are a survivor

In that very long line

Though life may seem struggle
The trend is adaptive

For those who adapt

This world a paradise

8. If You Would Know

Look to the strategies of individuals
Look to the survival of individuals
Look to the replication of individuals
Look to the reproduction of individuals
Look to the relatedness of individuals
Look to the relationships between individuals
Look to the competition between individuals
Look to the cooperation between individuals
Look to the dependencies between individuals
Look to the dependencies among individuals

Look to the survival of offspring
Look to the distinction of kinds

Look deep within each being
Look deep within the world too small for eyes
Look to the entities that replicate
Look to the communities of beings
Look to the interactions of beings

Look to the flow of information
Look to the flow of energy
Look to the flow of resources
Look to the flow of the world

Remember this:
The world is the blind selector
Indifferently differential