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Author Topic:   How is Natural selection a mechanism?
NosyNed
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Posts: 8954
From: Canada
Joined: 04-04-2003


Message 8 of 191 (522643)
09-04-2009 10:50 AM
Reply to: Message 6 by AndrewPD
09-04-2009 7:01 AM


Populations
You don't seem to have developed a feel for what goes on let me try please.

There are about 6 billion humans. In a generation each of those reproduces. About half of all reproductions end in failure very early on (maybe many of those failures are due to mutations but we don't know). The other half all carry several (in the 5 to 100 range) brand new mutations. These changes are separate from the new genetics produced by mixing the genes of the parents.

So each generation we get 6 billion new organisms and not all of those will survive and reproduce. That is a lot of chances for selection to work. In only 1,000 years we'll get about 300 billion new genomes.

Humans are a special case of course since a very large percentage do end up reproducing.

How about rats? They reproduce more than once a year and produce litters of (say) 5 (low btw). There are as many of them (or more) than us. They are cranking out perhaps 30 billion new genomes a year and less than 1/4 of them survive. The others are weeded out by bad luck and some are weeded out by natural selection. In 1,000 years we'll get about 30 trillion (30,000,000,000,000) new rats for natural selection to work on.

Natural selection works because nature is very, very, very inefficient. It is utterly wasteful. You see that more with other species where less than 1% of those born survive. There are literally astronomical numbers of new genomes produced each year and almost all of them are cast aside.

You can come up with almost anything if you just keep on trying things with no concern for being efficient. You just keep stirring the pot and seeing what happens.

Natural selection may only have a small effect on survival rates (that depends on the "selection pressure" as compared to just bad or good luck). But with billions and trillions of individuals to try out it can produce changes in the populations with only a small bias to the luck.


This message is a reply to:
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NosyNed
Member
Posts: 8954
From: Canada
Joined: 04-04-2003


Message 42 of 191 (529843)
10-10-2009 7:37 PM
Reply to: Message 40 by Kevin123
10-10-2009 6:41 PM


using sites
Haha, you ask me to provide a source but then in the same breath dismiss any source as lies. That's like me asking you for evidence in favor of evolution but not from any pro-evolution website because they all lie.

This is, intended or not, more of a favor to you. All the arguments on all those sites have been examined and ripped to pieces multiple times. If you use them you are making it easy for Coyote. Most of the time it is easy to demonstrate how they are wrong and that they are lying. Better you use something new from real evidence.

And please don't use the anti biotic resistant bacteria. Bacteria did not “mutate” after being exposed to antibiotics; the mutations conferring the resistance were present in the bacterial population even prior to the discovery or use of the antibiotics.

Experiments have been conducted which show conclusively that the mutations are not there in the first place. This is an example of you being fooled by lies from a creationist web site.


This message is a reply to:
 Message 40 by Kevin123, posted 10-10-2009 6:41 PM Kevin123 has not yet responded

  
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