Register | Sign In


Understanding through Discussion


EvC Forum active members: 65 (9162 total)
4 online now:
Newest Member: popoi
Post Volume: Total: 915,821 Year: 3,078/9,624 Month: 923/1,588 Week: 106/223 Day: 4/13 Hour: 0/2


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   The Definition for the Theory of Evolution
RAZD
Member (Idle past 1406 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 1 of 216 (409101)
07-07-2007 11:18 AM


Your opinion, Your Favorite
In the Basic Fundamentals of THE Debate (now open to anyone) we seem to have reached an impasse on what the definition for the theory of evolution is. The two basic opinions are:


(1) RAZD
Evolution is the (hereditary) change in species over time.
This is viewed as being essentially the same as "descent with modification" and "the change in frequency of alleles in populations" and is supported by (among others) the Forum Definition and Berkley University definition.
(2) Murkywaters
Message 87
The theory of evolution, on the other hand, can be stated as “All the living forms in the world have arisen over billions of years from a single common ancestor which itself came from an inorganic form.” This can be equated with the commonly used terms “macroevolution” (used by evolutionist) or simply “theory of evolution” (used by creationists).
For which there is apparently no specific cite for a basis that I can find.


The questions are:
(A) which is the better definition from a the standpoint of the science of evolution,
(B) what are the failings of each definition, and
(C) what is your personally preferred (concise) definition.
Thanks.


Biological Evolution Forum please.
Edited by RAZD, : brevity and clarity, subtitle

Join the effort to unravel AIDS/HIV, unfold Proteomes, fight Cancer,
compare Fiocruz Genome and fight Muscular Dystrophy with Team EvC! (click)


we are limited in our ability to understand
by our ability to understand
RebelAAmericanOZen[Deist
... to learn ... to think ... to live ... to laugh ...
to share.

Replies to this message:
 Message 3 by Modulous, posted 07-07-2007 3:31 PM RAZD has replied
 Message 4 by subbie, posted 07-07-2007 3:42 PM RAZD has not replied
 Message 20 by anastasia, posted 07-08-2007 1:40 AM RAZD has not replied
 Message 42 by Fosdick, posted 07-08-2007 4:36 PM RAZD has not replied
 Message 44 by Cold Foreign Object, posted 07-08-2007 6:01 PM RAZD has not replied
 Message 169 by Refpunk, posted 08-17-2007 10:00 AM RAZD has replied

AdminNem
Inactive Member


Message 2 of 216 (409130)
07-07-2007 2:57 PM


Thread moved here from the Proposed New Topics forum.

Modulous
Member
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 3 of 216 (409133)
07-07-2007 3:31 PM
Reply to: Message 1 by RAZD
07-07-2007 11:18 AM


my opinion, my Favorite
which is the better definition from a the standpoint of the science of evolution,
Definition 1
what are the failings of each definition, and
The first is a general overview of evolution, and the latter is a specific overview (ie, natural history). Neither is a definition of the theory of evolution.
what is your personally preferred (concise) definition.
The theory of evolution is a collection of mechanisms that describe how hereditary change in species over time happens.

This message is a reply to:
 Message 1 by RAZD, posted 07-07-2007 11:18 AM RAZD has replied

Replies to this message:
 Message 5 by subbie, posted 07-07-2007 3:51 PM Modulous has replied
 Message 8 by RAZD, posted 07-07-2007 4:54 PM Modulous has replied

subbie
Member (Idle past 1255 days)
Posts: 3509
Joined: 02-26-2006


Message 4 of 216 (409135)
07-07-2007 3:42 PM
Reply to: Message 1 by RAZD
07-07-2007 11:18 AM


Re: Your opinion, Your Favorite
Murkywaters's definition is incorrect based on things that it includes that are not necessary to the ToE as well as what he doesn't include.
He gives no description whatsoever of how the various organisms arose from a single common ancestor. RAZD's definition, however, at least explains something about how the process occurred, "the change in frequency of alleles in popluations."
Murky's definition includes two elements that are not necessary components of or conditions for the ToE; a common ancestor, and an inorganic beginning.
I'm not aware of anything in the ToE that rules out the possibility of more than one instance of life arising. Nor am I aware of anything the the ToE that rules out the possiblity of an extra terrestrial origin for the "seeds of life" which then grew and florished on this planet. While I do not believe that either of these ideas are commonly accepted as the most probable explanations, if evidence of either them were found, the ToE would be able to accomodate that evidence without any significant changes.
The only nit that I would pick with RAZD's definition is that it does not clearly lay out the process by which descent with modification takes place. As stated, it could encompass either Darwinian or Lamarkian change.

Those who would sacrifice an essential liberty for a temporary security will lose both, and deserve neither. -- Benjamin Franklin
We see monsters where science shows us windmills. -- Phat

This message is a reply to:
 Message 1 by RAZD, posted 07-07-2007 11:18 AM RAZD has not replied

Replies to this message:
 Message 23 by Doddy, posted 07-08-2007 7:32 AM subbie has not replied

subbie
Member (Idle past 1255 days)
Posts: 3509
Joined: 02-26-2006


Message 5 of 216 (409136)
07-07-2007 3:51 PM
Reply to: Message 3 by Modulous
07-07-2007 3:31 PM


Re: my opinion, my Favorite
The theory of evolution is a collection of mechanisms that describe how hereditary change in species over time happens.
I would say that's a description, not a definition. Here's my shot at it.
Populations change over time, mostly due to selective pressures to which the populations are subject, which enable those offspring better adapted to the environment to reproduce at a higher rate than those which are not. This change occurs because those organisms that are better adapted tend to pass on more of their genetic make up to the next generation.

Those who would sacrifice an essential liberty for a temporary security will lose both, and deserve neither. -- Benjamin Franklin
We see monsters where science shows us windmills. -- Phat

This message is a reply to:
 Message 3 by Modulous, posted 07-07-2007 3:31 PM Modulous has replied

Replies to this message:
 Message 6 by Modulous, posted 07-07-2007 4:22 PM subbie has replied

Modulous
Member
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 6 of 216 (409139)
07-07-2007 4:22 PM
Reply to: Message 5 by subbie
07-07-2007 3:51 PM


Re: my opinion, my Favorite
Populations change over time, mostly due to selective pressures to which the populations are subject, which enable those offspring better adapted to the environment to reproduce at a higher rate than those which are not. This change occurs because those organisms that are better adapted tend to pass on more of their genetic make up to the next generation.
Now that is a description of the theory, perhaps even an overview of the theory. You start your definition with a fact, and then go on to describe one factor which can cause the fact. I don't think it is possible to 'define' a theory. However it is possible to define the term 'The Theory of Evolution'. A definition should really be able to be tacked on to the prefix 'The theory of evolution is...'.
As to the question, 'what are these mechanisms that the theory describes?' we might turn to something like your description. We know that there are several mechanisms, selection being the one you focussed on and of course there is hereditary variation, neutral drift and epigenetics etc.
My concise statement tells you what the theory of evolution is, not what the mechanisms are, not how they operate or how they cause change...just a definition of The theory of Evolution
Edited by Modulous, : No reason given.

This message is a reply to:
 Message 5 by subbie, posted 07-07-2007 3:51 PM subbie has replied

Replies to this message:
 Message 7 by subbie, posted 07-07-2007 4:43 PM Modulous has replied

subbie
Member (Idle past 1255 days)
Posts: 3509
Joined: 02-26-2006


Message 7 of 216 (409141)
07-07-2007 4:43 PM
Reply to: Message 6 by Modulous
07-07-2007 4:22 PM


Re: my opinion, my Favorite
Well, let's see if we can't hone in on the guts of the topic without getting bogged down in semantics.
It seems to me that any definition or description of the ToE should be comprehensive enough to rule out alternative theories about how descent with modification may occur. In addition, it should not include things that are not part of the theory that someone might try to graft onto it in an effort to undermine it.

Those who would sacrifice an essential liberty for a temporary security will lose both, and deserve neither. -- Benjamin Franklin
We see monsters where science shows us windmills. -- Phat

This message is a reply to:
 Message 6 by Modulous, posted 07-07-2007 4:22 PM Modulous has replied

Replies to this message:
 Message 9 by RAZD, posted 07-07-2007 5:05 PM subbie has replied
 Message 11 by Modulous, posted 07-07-2007 6:14 PM subbie has not replied

RAZD
Member (Idle past 1406 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 8 of 216 (409142)
07-07-2007 4:54 PM
Reply to: Message 3 by Modulous
07-07-2007 3:31 PM


Re: my opinion, my Favorite
The first is a general overview of evolution, and the latter is a specific overview (ie, natural history). Neither is a definition of the theory of evolution.
The theory of evolution is a collection of mechanisms that describe how hereditary change in species over time happens.
In other words you want a set of mechanisms to say how evolution occurs referenced in the definition.
quote:
Message 17 (near the end)
  • change in species over time,
  • mutation as an observed fact,
  • natural selection as an observed fact, and
  • some other minor mechanisms such as genetic drift and horizontal gene transfer by viruses and the like.
    That it does NOT involve
  • sudden large scale change or
  • sudden appearance of whole new features or abilities.

Would that help? (those were my stipulations for microevolution).
Thanks.

Join the effort to unravel AIDS/HIV, unfold Proteomes, fight Cancer,
compare Fiocruz Genome and fight Muscular Dystrophy with Team EvC! (click)


we are limited in our ability to understand
by our ability to understand
RebelAAmericanOZen[Deist
... to learn ... to think ... to live ... to laugh ...
to share.

This message is a reply to:
 Message 3 by Modulous, posted 07-07-2007 3:31 PM Modulous has replied

Replies to this message:
 Message 12 by Modulous, posted 07-07-2007 6:22 PM RAZD has replied

RAZD
Member (Idle past 1406 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 9 of 216 (409144)
07-07-2007 5:05 PM
Reply to: Message 7 by subbie
07-07-2007 4:43 PM


Re: my opinion, my Favorite
How about something like:
The theory of evolution is
Life changes over time, due to hereditary mutations, natural selection, population dynamics, genetic drift and horizontal gene transfer by viruses and the like.
Thanks.

Join the effort to unravel AIDS/HIV, unfold Proteomes, fight Cancer,
compare Fiocruz Genome and fight Muscular Dystrophy with Team EvC! (click)


we are limited in our ability to understand
by our ability to understand
RebelAAmericanOZen[Deist
... to learn ... to think ... to live ... to laugh ...
to share.

This message is a reply to:
 Message 7 by subbie, posted 07-07-2007 4:43 PM subbie has replied

Replies to this message:
 Message 10 by subbie, posted 07-07-2007 5:27 PM RAZD has not replied

subbie
Member (Idle past 1255 days)
Posts: 3509
Joined: 02-26-2006


Message 10 of 216 (409146)
07-07-2007 5:27 PM
Reply to: Message 9 by RAZD
07-07-2007 5:05 PM


Re: my opinion, my Favorite
I think that's incomplete without including that some changes confer survival advantages on some organisms because of environmental pressures and that those organisms better adapted tend to prosper at the expense of those less well-adapted.

Those who would sacrifice an essential liberty for a temporary security will lose both, and deserve neither. -- Benjamin Franklin
We see monsters where science shows us windmills. -- Phat

This message is a reply to:
 Message 9 by RAZD, posted 07-07-2007 5:05 PM RAZD has not replied

Replies to this message:
 Message 13 by Modulous, posted 07-07-2007 6:24 PM subbie has replied

Modulous
Member
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 11 of 216 (409161)
07-07-2007 6:14 PM
Reply to: Message 7 by subbie
07-07-2007 4:43 PM


Re: my opinion, my Favorite
Well, let's see if we can't hone in on the guts of the topic without getting bogged down in semantics.
Hehehe, a discussion on definitions getting bogged down by the meaning of words?
It seems to me that any definition or description of the ToE should be comprehensive enough to rule out alternative theories about how descent with modification may occur. In addition, it should not include things that are not part of the theory that someone might try to graft onto it in an effort to undermine it.
Yes - if we were going to describe the theory of evolution that is currently accepted by a consensus of those that study it - but such a thing is difficult to do concisely. If we are to give it a name it would probably be 'The Synthetic Theory of Evolution'. It is a synthesis of a number of theories, such as Darwinism and Mendelian genetics as well as more modern theories stemming from our understanding of genetics. I suppose you could define the synthetic theory like this site does:
quote:
Synthesis of Mendelian genetics and Darwinian selection into a modern theory of evolutionary change.
Or this one:
quote:
[The Synthetic Theory is] essentially a combination of Charles Darwin's concept of natural selection, Gregor Mendel's basic understanding of genetic inheritance, along with evolutionary theories developed since the early 20th century by population geneticists and more recently by molecular biologists
Trying to include all of the mechanisms into the definition will fall foul of the original parameter by being necessarily verbose. Probably the size of a book or more likely several hundred books - just see how wordy Gould got in his 'The Structure of Evolutionary Theory'

This message is a reply to:
 Message 7 by subbie, posted 07-07-2007 4:43 PM subbie has not replied

Replies to this message:
 Message 110 by RAZD, posted 07-14-2007 7:21 PM Modulous has replied

Modulous
Member
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 12 of 216 (409163)
07-07-2007 6:22 PM
Reply to: Message 8 by RAZD
07-07-2007 4:54 PM


Re: my opinion, my Favorite
In other words you want a set of mechanisms to say how evolution occurs referenced in the definition.
Quite the contrary, I don't think it is possible, not without losing the concise edge. If I am going to describe the theory of evolution I would say it includes natural selection, hereditary variation, neutral drift and epigenetics to name a few but I would be more keen to draw a line between the phenomenon and the theory that explains the phenomenon.
What is the theory of evolution? It is the theory that explains the phenomenon of evolution. It is a body of knowledge of hypotheses and theories that, when combined help explain all the ways we know how population changes can occur under certain circumstances. Those circumstances are present in life and so the theory can help explain the evolution of biological life. Some examples of these sub-theories include the process of natural selection acting on hereditary variations, neutral genetic drift, recombination of recessive and dominant traits and so on and so forth.

This message is a reply to:
 Message 8 by RAZD, posted 07-07-2007 4:54 PM RAZD has replied

Replies to this message:
 Message 17 by RAZD, posted 07-07-2007 9:04 PM Modulous has not replied

Modulous
Member
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 13 of 216 (409164)
07-07-2007 6:24 PM
Reply to: Message 10 by subbie
07-07-2007 5:27 PM


Re: my opinion, my Favorite
I think that's incomplete without including that some changes confer survival advantages on some organisms because of environmental pressures and that those organisms better adapted tend to prosper at the expense of those less well-adapted.
Realising that this might be going down the route of pedantic semantics, but you've just described in more detail one item on RAZD's list: natural selection.

This message is a reply to:
 Message 10 by subbie, posted 07-07-2007 5:27 PM subbie has replied

Replies to this message:
 Message 14 by subbie, posted 07-07-2007 6:29 PM Modulous has not replied

subbie
Member (Idle past 1255 days)
Posts: 3509
Joined: 02-26-2006


Message 14 of 216 (409165)
07-07-2007 6:29 PM
Reply to: Message 13 by Modulous
07-07-2007 6:24 PM


Re: my opinion, my Favorite
Yes, you're quite right.
My bad.

Those who would sacrifice an essential liberty for a temporary security will lose both, and deserve neither. -- Benjamin Franklin
We see monsters where science shows us windmills. -- Phat

This message is a reply to:
 Message 13 by Modulous, posted 07-07-2007 6:24 PM Modulous has not replied

Replies to this message:
 Message 15 by Grizz, posted 07-07-2007 7:31 PM subbie has not replied

Grizz
Member (Idle past 5472 days)
Posts: 318
Joined: 06-08-2007


Message 15 of 216 (409167)
07-07-2007 7:31 PM
Reply to: Message 14 by subbie
07-07-2007 6:29 PM


Re: my opinion, my Favorite
I would vote for the forum defintion.
For an operational definition of what an evolutionary scientist does I would say: A study of natural mechanisms that can lead to changes in a genome over time.

This message is a reply to:
 Message 14 by subbie, posted 07-07-2007 6:29 PM subbie has not replied

Replies to this message:
 Message 16 by Wepwawet, posted 07-07-2007 8:48 PM Grizz has not replied

Newer Topic | Older Topic
Jump to:


Copyright 2001-2023 by EvC Forum, All Rights Reserved

™ Version 4.2
Innovative software from Qwixotic © 2024