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Author Topic:   Does the history of life require "macroevolution"?
Modulous
Member (Idle past 894 days)
Posts: 7789
From: Manchester, UK
Joined: 05-01-2005


Message 61 of 127 (815024)
07-14-2017 3:16 PM
Reply to: Message 55 by Faith
07-14-2017 1:54 PM


Re: Genes are more complex than that
The complexisties you describe don't suggest any kind of change that would promote evolution beyond the Kind

Evolution doesn't go beyond the Kind. It modifies the kind, never goes beyond it. Hence why we are still mammals, still tetrapods. It's just we are modified mammal kinds.

it's all still changes to genes

Which is fine.

and even if those functions change they are still genes for those functions

Evolution doesn't change the laws of physics. The functions change, that's evolution. The fact that genotypes influence phenotypes isn't the thing that changes. So this is not a valid objection.

they aren't going to produce something outside the range of what genes do

Nobody is proposing that genes do things that genes can't do.

which would be necessary for evolution beyond the Kind.

Therefore evolutionary biologists are not proposing evolution beyond the Kind.

Thank you for that basic acknowledgement that selection requires loss. As I keep arguing, domestic breeding is still the best example, it doesn't matter where the genetic diversity comes from it still has to be lost by selection to get new phenotypes characteristic of a breed or species, and the end result of the selective processes, which produce those new phenotypes, HAS to be loss.

There doesn't have to be loss to get the new phenotypes necessarily. The loss is only in the process of increasing the frequency of certain phenotypes relative to others.

There HAS to be a point in a series of such evolutionary processes where genetic diversity is reduced to the point that further evolution cannot happen, a hypothetical point in most cases but sometimes real.

There doesn't have to be such a point.

As I keep arguing, domestic breeding is still the best example, it doesn't matter where the genetic diversity comes from it still has to be lost by selection to get new phenotypes characteristic of a breed or species, and the end result of the selective processes, which produce those new phenotypes, HAS to be loss.

And yet, even though purebreeding is an exercise at creating new animals that minimally diverge from the 'exemplar' - that is it is a deliberate attempt to reduce diversity - change still happens:

https://dogbehaviorscience.wordpress.com/...reed-improvement

Just a 100 years or so.

IF YOU GET MUTATIONS AT THAT POINT you start losing the species,

Also known as 'evolution'.

you go back to genetic diversity, you get a motley collection of new phenotypes, not an identifiable species

Except selection is also continuing to happen, which may take a motley collection and push it in a different direction from the original phenotype. That is to say: evolution.

A hedge trimmed into a primitive mammalian predator is allowed to grow out, and is then trimmed into a wolf, it grows out, and is trimmed into a domestic dog. The loss of leaves and twigs is intrinsic to the process, but so is the growth of new leaves and twigs.

And again, mutations don't change the basic function of a gene even if that gene involves more than one function.

If it loses the original function, while retaining the secondary function - the function of the gene has changed.

For instance, dogs have stiff bodies, cats have flexible bodies. What parts of the genome affect those structural differences?

HOX genes are significant players. There are also a multitude of genes that regulate their expression amongst likely many others that are involved.

Edited by Modulous, : No reason given.


This message is a reply to:
 Message 55 by Faith, posted 07-14-2017 1:54 PM Faith has not yet responded

  
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