Random mutations

[CabVet]

There seems to be a general misunderstanding around here. A lot of people are saying that evolution is random and that mutations are "magical" or "imaginary" events. So, I will try to clarify this. I will start with a few definitions:

Mutation: A mutation is a change in DNA, the hereditary material of life.

DNA (deoxyribonucleic acid): A nucleic acid that carries the genetic information in the cell and is capable of self-replication and synthesis of RNA.

RNA (ribonucleic acid): A class of single-stranded molecules transcribed from DNA in the cell, containing a linear sequence complementary to the DNA strand from which it was transcribed.

 

[CabVet]

What causes DNA mutations?

Mutations in DNA sequences generally occur through one of two processes:

• DNA damage from environmental agents such as ultraviolet light (sunshine), nuclear radiation or certain chemicals;
• Mistakes that occur when a cell copies its DNA in preparation for cell division.

 

[CabVet]

Mutations cause changes in gene expression, gene products and may completely change how an organism looks (or behaves, or functions). Most deleterious mutations decrease in frequency until they disappear from populations, simply because individuals carrying deleterious mutations do not reproduce as often as those not carrying them. The opposite is true for advantageous mutations. Their tendency is to increase in frequency in any population, because the individuals carrying advantageous mutations reproduce more often.

At a given point in time, there is a lot of variation within every species. See humans for example, we have many races, sizes, shapes. It is this variation that is the raw material for natural selection to act upon.

 

[sfs]

What causes DNA mutations?

Mutations in DNA sequences generally occur through one of two processes:

• DNA damage from environmental agents such as ultraviolet light (sunshine), nuclear radiation or certain chemicals;
• Mistakes that occur when a cell copies its DNA in preparation for cell division.

Many mutations are also caused by spontaneous chemical processes, e.g. tautomerization and the spontaneous deamination of methylated cytosine.

 

[CabVet]

Many mutations are also caused by spontaneous chemical processes, e.g. tautomerization and the spontaneous deamination of methylated cytosine.

Yes, I am just trying to keep it simple since some people around here are comparing mutations to deities.

 

[Jazer]

Mutation: A mutation is a change in DNA, the hereditary material of life.

Then show us the change. For example,
show us the mutation that transformed man
from a hunter gatherer into a farmer hurder.

 

[CabVet]

Then show us the change. For example,
show us the mutation that transformed man
from a hunter gatherer into a farmer hurder.

There is no mutation involved in cultural changes in the way a society works.

 

[Phred]

Then show us the change. For example,
show us the mutation that transformed man
from a hunter gatherer into a farmer hurder.

Hold on... are you sure that a change in culture can be attributed to our genes?

 

[CabVet]

Hold on... are you sure that a change in culture can be attributed to our genes?

Do you see why I started the thread?

 

[Notedstrangeperson]

Then show us the change. For example,
show us the mutation that transformed man
from a hunter gatherer into a farmer hurder.

There is no mutation involved in cultural changes in the way a society works.

Hold on... are you sure that a change in culture can be attributed to our genes?

That's actually a very good question. Culture is generally not considered to be the result of genes, but there's a great deal of interest as to whether genes are shaped by culture.

BTW CabVet - while everything you're written is true, this doesn't change the fact that most mutations (especially natural mutations) are actually quite random.

 

[CabVet]

That's actually a very good question. Culture is generally not considered to be the result of genes, but there's a great deal of interest as to whether genes are shaped by culture.

BTW CabVet - while everything you're written is true, this doesn't change the fact that most mutations (especially natural mutations) are actually quite random.

Genes are shaped by the environment (meaning they are filtered by the environment). Of course a society that farms will have more resources than one that hunts, and therefore more offspring.

Mutations are random, evolution is not, this is the point of the thread.

 

[Notedstrangeperson]

Mutations are random, evolution is not, this is the point of the thread.

Fair enough.

Genes are shaped by the environment (meaning they are filtered by the environment). Of course a society that farms will have more resources than one that hunts, and therefore more offspring.

A thread about how culture effects genes (or vice-versa?) would be even more interesting.

 

[Zaius137]

One might ask if evolution is not random then how can it originate from a random mutation?

 

[CabVet]

Evolution does not originate from a random mutation. Random mutations produce variation within every population (black, white, asian people, etc). Evolution (or natural selection) eliminates variation that has a poor fitness and favors variation that has a good fitness.

 

[Loudmouth]

One might ask if evolution is not random then how can it originate from a random mutation?

The same way that rain can fall randomly on the surface of the Earth but the rivers where this rain gathers always flows downhill. Adaptation is not random. It always proceeds from lower fitness to higher fitness in the same way that water always flows downhill.

 

[FrenchyBearpaw]

One might ask if evolution is not random then how can it originate from a random mutation?

"...by means of natural selection."

 

[Jazer]

Hold on... are you sure that a change in culture can be attributed to our genes?

I am not sure of anything after the conversation about what fire and cooking our food has to do with evolution. I am pretty sure that evos make this stuff up as they go along.

 

[CabVet]

I am not sure of anything after the conversation about what fire and cooking our food has to do with evolution. I am pretty sure that evos make this stuff up as they go along.

You should read about it, maybe you could gain some insight and debate a little better. It would be really disrespectful of me if I tried to convince you that Christianity is wrong if I didn't know what Christianity was, wouldn't it?

 

[Phred]

I am not sure of anything after the conversation about what fire and cooking our food has to do with evolution. I am pretty sure that evos make this stuff up as they go along.

Then you haven't been paying attention.

 

[Jazer]

Culture is generally not considered to be the result of genes

I guess your idea of Culture is different than mine. Now they are suggesting that the ability to dance is genetic. Of course there are others that do not agree. For example:

"The success of 'Strictly Dance Fever' shows how far people are prepared to push themselves to succeed as dancers. But research from Israel suggests that some may have an advantage: they may be genetically better suited to dancing.
Richard Ebstein and colleagues studied 85 professional dancers and their parents, 91 athletes, and a control group of 'ordinary' people. They used questionnaires to test their personalities and looked at genetic variation around two genes known to affect social behaviour in animals: the serotonin transporter (SLC6A4) and the arginine vasopressin receptor 1a (AVPR1a).
The researchers found good correlations between dancers and personality measures such as the need for social contact and high spirituality, but also with variations around both the genes studied. Moreover, the personality traits also independently correlated with the genetic variation. The results, say the researchers, suggest that the genetic factors are promoting participation in dance, by influencing personality rather than body mechanics or coordination." Dancing gene | The Human Genome