How do you define the word Evolution?

Message 1 of 936 (259689) 11-14-2005 4:10 PM

How do you define evolution? I ask you to post your definition of evolution.

Why? Because over and over I see arguments based on differing opinions of the words being used. If we lack a common definition, we can scarcely be successful in our discussions. I suspect that evolution is one of those key words that evoke many different concepts in the minds of the readers and writers. With this thread, we may be able to see and understand some of those differences.

I ask that all definitions be less than 90 words in total. Keep it short, clear, and to the point. No justifications, no rationales, no references. Don’t go look it up then write what you read in your own words. Just post your concise opinion. Note that for reference, this paragraph, including these last sentences, contains 90 words as counted by Microsoft Word. I have added a little extra BS just to get this close to the exact value so we will have an easy reference. Three more words.

Before you make any arguments to support your position or to dispute other positions, please allow a few days for everyone to post their opinion. I wish to see each person's mental concept of the word evolution.

Message 2 of 936 (259691) 11-14-2005 4:17 PM

Reply to: Message 1 by bkelly 11-14-2005 4:10 PM

The change in species over time due to descent with modification and natural selection.

More modern definition:

The change over time of the genetic makeup of species through natural selection operating on accumulated genetic variation and mutations.

--Percy

Message 4 of 936 (259702) 11-14-2005 5:10 PM

Reply to: Message 1 by bkelly 11-14-2005 4:10 PM

the variation in frequency of heritable features in a population between generations.

Message 5 of 936 (259740) 11-14-2005 6:55 PM

More relevant to this, in the realm of biology,
Changes in the makeup of a population through hereditary attributes which allow that population to survive in a given environment.

I'm trying to be as vague/broad as possible to encompass all situations.

Message 6 of 936 (259756) 11-14-2005 11:04 PM

bkelly

Message 7 of 936 (259757) 11-14-2005 11:07 PM

In a biological context - common descent and change over time between generations.

Message 8 of 936 (259782) 11-15-2005 12:10 AM

Sometime people, here and elsewhere, get snooty when you use the term "evolution" for things outside of biology. I say "screw them". :)

Originally the "Biological Evolution" forum was the "Evolution" forum. The name change was made to exclude non-biological evolution themes.

Moose

Message 9 of 936 (259809) 11-15-2005 1:44 AM

And since my definition is so concise, I'll use up some of the remainder of my 90 word issue by offering one of my favorite poems, brought to mind by this:

Oh, never mind.

Message 10 of 936 (259918) 11-15-2005 10:48 AM

When a descendant’s inheritable characteristics differ from those of its parent(s).

This includes when a trait changes from dominant to recessive or the reverse.

I define it this way in part because I had one person tell me that changes caused by humans (such as dogs from wolves and new strains of mice) don't count as evolution. Only changes that happen in nature (not human caused) are evolution.

bkelly

Message 11 of 936 (259922) 11-15-2005 11:08 AM

Reply to: Message 1 by bkelly 11-14-2005 4:10 PM

PS.( not incl. in 90 words!) this is my first post to EvC! been a lurker for a few months now, and finally decided to shrug off my cloak of invisibility!

Message 12 of 936 (259983) 11-15-2005 2:55 PM

Reply to: Message 1 by bkelly 11-14-2005 4:10 PM

Biological evolution is a change in an allele frequency of a population.

Why would you need 90 words?

Message 13 of 936 (259993) 11-15-2005 3:29 PM

Reply to: Message 1 by bkelly 11-14-2005 4:10 PM

In biological evolution, the units of analysis is usually a species, with change due to mutation and the interaction of species with environment which must allow them to continue to reproduce (i.e. natural selection)

But not all biological evolution has these units of analysis, and other things that may usefull be called evolution have different units of analysis.

Ben

Message 14 of 936 (260050) 11-15-2005 8:59 PM

Reply to: Message 11 by U can call me Cookie 11-15-2005 11:08 AM

Since you did, I will admit some ignorance and ask for an explanation.

allele
noun: one of two alternate forms of a gene that can have the same locus on homologous chromosomes and are responsible for alternative traits

homologous
adj: having the same evolutionary origin but serving different functions
adj: corresponding or similar in position or structure or function or characteristics

When I apply these specific definitions to your definition I find my self no better off and need some help here. This definition of evolution seems to restrict it to changes that occur to genes that come in two alternate forms and in the same location. That seems like an unnecessary restriction. To me, any gene that changes from parent to offspring represents evolution to some degree regardless of what or where that gene is. And why must there be a change in frequency? I have seen that phrase several times and have yet to understand it.

When you write or speak the word evolution is this the definition that you have in mind?

Again, thank for joining us.

bkelly

Message 15 of 936 (260057) 11-15-2005 9:04 PM

Reply to: Message 12 by New Cat's Eye 11-15-2005 2:55 PM

Obviously we don't. I was and am hoping that some that hold the concept of evolution to be false would post their definition. It occured to me that they might want to explain and to ensure that I understood, I wanted the answer short and simple.