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Macroevolution Observed?

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Author Topic:   Macroevolution Observed?
RAZD
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Posts: 20714
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Joined: 03-14-2004

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Message 14 of 55 (92864)
03-17-2004 1:04 AM 		Reply to: Message 13 by DC85
03-16-2004 9:37 PM

The mechanisms that cause microevolution and macroevolution are the same, the only difference is the degree of difference between the results. Macroevolution would be hard to observe as it requires more differentiation between end results than speciation, so it would need to follow several speciation events ... definitely a time-limiting problem for a short lived species like Homo sapiens to undertake.
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A good site to look at for answers is
29+ Evidences for Macroevolution: Part 1
It is a long read with a lot of ground to cover.
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A simpler one is on therapsids at
http://www.geocities.com/...naveral/Hangar/2437/therapsd.htm
As it just covers the evolution of the mammal ear from the reptilian one and the associated changes to the jaw bones and hinges ... but reptile to mammal is about as macro as one should need to get to sink the "kind" issue.
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For creationists these terms tend to be moveable goal posts in the same way that "kind" has been used. They will state that they accept microevolution as it is only differentiation within a kind, but that macro has not been observed -- so whenever an observation occurs both terms get redefined to the next step in the ladder.
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Enjoy
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RAZD
Member (Idle past 1436 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004

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Message 24 of 55 (94692)
03-25-2004 12:13 PM 		Reply to: Message 22 by PaulK
03-25-2004 10:38 AM

understanding
I think he(?) misinterpreted your original post to say that
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group (A) was interbreeding within the group while
group (B) was not interbreeding within the group
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(which would be a different process) rather than
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group (A) was interbreeding within the group and
group (B) was interbreeding within the group and
group (A) was no longer interbreeding with group (B)
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thus allowing divergence of group (A) from group (B) while maintaining convergence within each group.
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hope that helps.
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we are limited in our ability to understand
by our ability to understand
​
RebelAAmerican.Zen[Deist
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Replies to this message:
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 Message 26 by Milagros, posted 03-25-2004 2:30 PM RAZD has replied
  
RAZD
Member (Idle past 1436 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004

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Message 28 of 55 (94740)
03-25-2004 3:06 PM 		Reply to: Message 26 by Milagros
03-25-2004 2:30 PM

Re: understanding
Before you laugh too loud, I made another response to your post #25 before this (though I haven't seen it come up yet) and I repeat it here:
It looks like I was right.
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Please read my previous post again. There is no {"non-interbreeding" population}, but two distinct {interbreeding populations} where cross-breeding no longer occurs between the two groups even though it continues within each group.
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A simple example would be a lake where the water level falls until the lake is divided into two distinct lakes and the fish in one become separated from the fish in the other. Each group would continue to interbreed among themselves but are now incapable of interbreeding with the fish in the other lake in spite of a long and colorful history of interbreeding before the lake level fell.
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This allows the two groups to diverge due to different mutations accumulated over time.
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Years later the lake level rises, the fish commingle, but are now unable to interbreed between the two groups due to genetic changes that have accumulated in each group since the fish were separated: speciation.
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Enjoy.
My post #24 was referring to your misconception of the breeding patterns within each group after separation into two groups from the parent group -- your misconception of where "non-interbreeding" fits into the picture.
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Note that there is no need for both groups to diverge significantly from the parent population, in fact one could remain {species consistent} with the parent group while the other diverges from it into a new species, but that in both cases each population interbreeds within the population. Nor is there need for the lake level to rise for the speciation event to have occured.
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Let me know if this is not specific enough for you.
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AL.
​
we are limited in our ability to understand
by our ability to understand
​
RebelAAmerican.Zen[Deist
This message is a reply to:
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RAZD
Member (Idle past 1436 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004

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Message 31 of 55 (94856)
03-25-2004 10:30 PM 		Reply to: Message 30 by Milagros
03-25-2004 9:42 PM

lake control
so
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you are saying that the macroevolution of the fish causes the level of the lake to drop thus magically seperating the two species into the two remaining bodies of water -- magically because not one of either species gets left in the wrong lake ...
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faxcicanating ...
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I've heard of magic koalas before, and now magic fish.
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wonderful.
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we are limited in our ability to understand
by our ability to understand
​
RebelAAmerican.Zen[Deist
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RAZD
Member (Idle past 1436 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004

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Message 45 of 55 (94995)
03-26-2004 3:55 PM 		Reply to: Message 44 by Milagros
03-26-2004 3:32 PM

try this posting by Quetzal:
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http://EvC Forum: What is your favorite example of speciation?
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speciation occurs when two varieties of a species become so different from accumulated change that they no longer are capable of interbreeding.
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and yet each level of change that occurs is your "micro" evolutionary change
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"macro" = sum (enough "micro")
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we are limited in our ability to understand
by our ability to understand
​
RebelAAmerican.Zen[Deist
This message is a reply to:
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RAZD
Member (Idle past 1436 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004

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Message 49 of 55 (95038)
03-26-2004 11:11 PM 		Reply to: Message 47 by Corkscrew
03-26-2004 9:26 PM

Re: Definitions
the enlightened version:
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I pledge allegiance to the flag
Of the United States of America
And to the republic for which it stands
One nation, indivisible,
With liberty, justice and equality for all.
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we are limited in our ability to understand
by our ability to understand
​
RebelAAmerican.Zen[Deist
This message is a reply to:
 Message 47 by Corkscrew, posted 03-26-2004 9:26 PM Corkscrew has not replied
  
RAZD
Member (Idle past 1436 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004

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Message 50 of 55 (95040)
03-26-2004 11:17 PM 		Reply to: Message 48 by Intruder
03-26-2004 10:48 PM

macrame mini-me
I believe both Gould and Dawkins have used the terms, Gould in his paper on punctuated equilibrium. It does need to be defined to use: currently it is drifting above speciation for most creationists ... Several instances of speciation have been shown, so that would be why.
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we are limited in our ability to understand
by our ability to understand
​
RebelAAmerican.Zen[Deist
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 Message 48 by Intruder, posted 03-26-2004 10:48 PM Intruder has replied
Replies to this message:
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RAZD
Member (Idle past 1436 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004

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Message 52 of 55 (95049)
03-27-2004 12:05 AM 		Reply to: Message 51 by Intruder
03-26-2004 11:42 PM

Re: macrame mini-me
By drifting above I mean that speciation is being moved into micro-evolution and the evidence for it gets too overwhelming ...
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Prediction: "macro" will continue to move up the cladistic levels as evidence accumulates so that creationist can continue to say it has not been observed.
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This is like the definition of "kind" ... if fact they are essentially the same distinction.
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we are limited in our ability to understand
by our ability to understand
​
RebelAAmerican.Zen[Deist
This message is a reply to:
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Replies to this message:
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