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This is a little tricky.

First of all lets be clear about 'bringing together favorable alleles' (or any alleles) represented by site mutations on 2 chromosomes:

--------A------------------
             X     
------------------B--------

If the two dashed lines are two copies of the same chromosome, then a recombination event at X may produce:

--------A---------B--------

Allowing both A and B to be passed along to offspring. Any given case of recombination might actually harm resulting offspring. But in cases where A and B together are beneficial, over the course of generations you will find AB genotype combinations show up more frequently in the population because of selection and competition.

So its not just recombination, but recombination and selection which create favourable combinations of alleles in populations.

By comparison, consider a simple case where recombination does not occur where there is an A genotype and then one waits for B to show up on the same chromosome by random mutation. That would take perhaps thousands or even millions of generations before such a thing happens at random. Recombination is a powerful accelerator of evolution.

This is a little tricky.

First of all lets be clear about 'bringing together favorable alleles' (or any alleles) represented by site mutations on 2 chromosomes:

--------A------------------
             X     
------------------B--------

If the two dashed lines are two copies of the same chromosome, then a recombination event at X may produce:

--------A---------B--------

Allowing both A and B to be passed along to offspring.

Any given case of recombination might actually harm resulting offspring. But in cases where A and B together are beneficial, over the course of generations you will find AB genotype combinations show up more frequently in the population because of selection and competition.

Firstly each individual variant experiences some selection for fitness and many are lost. Because of this, recombination will typically put two or more such variants together onto a single chromosome. Recombination allows for individual mutations of benefit to pool together and collect into a single place. This multiplies the chance that stronger combinations of mutations will show in the gene pool. This increases the fitness variance - the most powerful combinations are more beneficial than any single variant alone. On the other end detrimental combinations will also make some individuals exceptionally weak.

So its not just recombination, but recombination and selection which create favorable combinations of alleles in populations. The link you give discusses how when selection is not strong, recombination is not so great, but we never seem to lose recombination where these conditions don't hold sway.

By comparison, consider a simple case where recombination does not occur where there is an A genotype and then one waits for B to show up on the same chromosome by random mutation. That would take perhaps thousands or even millions of generations before such a thing happens at random. Recombination is a powerful accelerator of evolution.

This is a little tricky.

First of all lets be clear about 'bringing together favorable alleles' (or any alleles) represented by site mutations on 2 chromosomes:

--------A------------------
             X     
------------------B--------

If the two dashed lines are two copies of the same chromosome, then a recombination event at X may produce:

--------A---------B--------

Allowing both A and B to be passed along to offspring. Any given case of recombination might actually harm resulting offspring. But in cases where A and B together are beneficial, over the course of generations you will find AB genotype combinations show up more frequently in the population because of selection and competition.

So its not just recombination, but recombination and selection which create favourable combinations of alleles in populations.

But consider a simple case where recombination does not come in. You may have an A genotype and then wait for B to show up by random mutation. That would take perhaps thousands or even millions of generations before such a thing happens at random. Recombination is a powerful accelerator of evolution.

This is a little tricky.

First of all lets be clear about 'bringing together favorable alleles' (or any alleles) represented by site mutations on 2 chromosomes:

--------A------------------
             X     
------------------B--------

If the two dashed lines are two copies of the same chromosome, then a recombination event at X may produce:

--------A---------B--------

Allowing both A and B to be passed along to offspring. Any given case of recombination might actually harm resulting offspring. But in cases where A and B together are beneficial, over the course of generations you will find AB genotype combinations show up more frequently in the population because of selection and competition.

So its not just recombination, but recombination and selection which create favourable combinations of alleles in populations.

By comparison, consider a simple case where recombination does not occur where there is an A genotype and then one waits for B to show up on the same chromosome by random mutation. That would take perhaps thousands or even millions of generations before such a thing happens at random. Recombination is a powerful accelerator of evolution.

This is a little tricky.

First of all lets be clear about 'bringing together favorable alleles' (or any alleles) represented by site mutations on 2 chromosomes:

--------A------------------
             X     
------------------B--------

If the two dashed lines are two copies of the same chromosome, then a crossover at X may produce:

--------A---------B--------

Allowing both A and B to be passed along to offspring. Any given case of recombination might actually harm resulting offspring. But in cases where A and B together are beneficial, over the course of generations you will find AB genotype combinations show up more frequently in the population because of selection and competition.

So its not just recombination, but recombination and selection which create favourable combinations of alleles in populations.

But consider a simple case where recombination does not come in. You may have an A genotype and then wait for B to show up by random mutation. That would take perhaps thousands or even millions of generations before such a thing happens at random. Recombination is a powerful accelerator of evolution.

This is a little tricky.

First of all lets be clear about 'bringing together favorable alleles' (or any alleles) represented by site mutations on 2 chromosomes:

--------A------------------
             X     
------------------B--------

If the two dashed lines are two copies of the same chromosome, then a recombination event at X may produce:

--------A---------B--------

Allowing both A and B to be passed along to offspring. Any given case of recombination might actually harm resulting offspring. But in cases where A and B together are beneficial, over the course of generations you will find AB genotype combinations show up more frequently in the population because of selection and competition.

So its not just recombination, but recombination and selection which create favourable combinations of alleles in populations.

But consider a simple case where recombination does not come in. You may have an A genotype and then wait for B to show up by random mutation. That would take perhaps thousands or even millions of generations before such a thing happens at random. Recombination is a powerful accelerator of evolution.