Radishes and Evolution

[Canuckster1127]

http://www.sciencedaily.com/releases/20 ... 233418.htm

This article basically recounts an occurance in California of a hybrid plant development between the normal every day radish and a weed refered to as the jointed charlock. The assertion is that in the wild, the wild radish variant has taken over and the orginal weed is now gone. This in an observable period of 100 years which is considered amazingly fast in evolutionary terms.

Two implications are drawn from the study cited.

First in terms of conservation the need for a realization that such man-affected change can take place. The question hanging here, in my mind, would be, what they think we need to do practically, or can do?

The second implication is found in this quote from the article,

"We found that wild radish in California has now become an evolutionary entity separate from both of its parents," said Ellstrand, a co-author of the paper. "It can serve as an excellent model organism for evolutionary studies."

Perhaps it can, and yet by their definition at the beginning of the article this is apparently a somewhat unusual and accelerated example. What would be the benefit of utilizing such an example as a model if by definition it falls at the edge of the supposed bell curve?

Any thoughts?

[thereal]

This is just my personal observation, but often times when a species is referred to in relation to being a "model" system, it's not because it is representative of the concept in general, but rather because it exhibits the process in question relatively fast and can be manipulated or observed easily. For example, fruit flies are described as model systems for genetic studies, but they are obviously not representative of all or even most species. Rather, they are model species because they have very short generation times are are thus conducive to studies of inheritance. Whether it's misrepresentation or simply semantics, this is what I'm familiar with when things are described as "model" systems.

[Canuckster1127]

This is just my personal observation, but often times when a species is referred to in relation to being a "model" system, it's not because it is representative of the concept in general, but rather because it exhibits the process in question relatively fast and can be manipulated or observed easily. For example, fruit flies are described as model systems for genetic studies, but they are obviously not representative of all or even most species. Rather, they are model species because they have very short generation times are are thus conducive to studies of inheritance. Whether it's misrepresentation or simply semantics, this is what I'm familiar with when things are described as "model" systems.

Good point. I agree that is what they are saying in terms of the ability to observe and understand the process.

I just wonder if, in view of more actual occurances taking place over longer periods of time, that fact alone makes the using of a shorter term occurance for a model, suspect in and of itself.

[BGoodForGoodSake]

First in terms of conservation the need for a realization that such man-affected change can take place. The question hanging here, in my mind, would be, what they think we need to do practically, or can do?

It's not a man affected change which they are focusing on. The focus is on invasive species in general. And on gene pool segregation specifically.

The second implication is found in this quote from the article,

"We found that wild radish in California has now become an evolutionary entity separate from both of its parents," said Ellstrand, a co-author of the paper. "It can serve as an excellent model organism for evolutionary studies."

Perhaps it can, and yet by their definition at the beginning of the article this is apparently a somewhat unusual and accelerated example. What would be the benefit of utilizing such an example as a model if by definition it falls at the edge of the supposed bell curve?

There are two distinct topics which you seem to be mixing up here. The overtaking of parent populations by a hybrid population is what is rare.

In terms of it serving as a model for evolution, what we are looking at is how a child species can differentiate itself from the parent species, while cohabitating.

The model which will be helpful to conservationists and scientists alike is the rapid manor in which one species can replace another.

[Canuckster1127]

OK. That helps.

I don't have a problem with what they are saying. Perhaps my over-developed "over-statement detector" went off a little prematurely.

[Gman]

Perhaps it can, and yet by their definition at the beginning of the article this is apparently a somewhat unusual and accelerated example.

Hey Bart, since I live here in California. I would say that there are a lot of unusual and accelerated weird things around here... Don't get too shocked by it all...

G -