A Natural Selection

The New York Times ^ | July 22, 2008, 7:44 pm | Olivia Judson

[Soliton]

Field mustard. Between 2000 and 2004, southern California had a severe drought. For many plants, including field mustard (a scrawny annual plant with little yellow flowers), a drought means a shorter growing season. A shorter growing season means that plants that flower earlier are more likely to leave seeds than plants that flower later — which are in danger of dying before they’ve finished reproducing. Since flowering time has a large genetic component, a drought — by favoring plants that flower earlier — could cause an evolutionary shift towards early flowering. Has it? Yes. The beauty of plants is that they make seeds — small packets of genes that can be stored for a period. This means that the genes of the past can, in principle, be compared directly with the genes of today. And an experiment in which field mustard plants grown from seeds collected in 1997 and in 2004 were planted together, under controlled conditions, showed clear differences in flowering times: the plants from 2004 flowered significantly earlier. Moreover, in both years, seeds were collected from two sites, one where the soil is sandy and doesn’t hold water well, and the other where the soil stays wet for longer. As you’d expect, plants from the dry site showed a more dramatic shift than plants from the wet site. In the course of just 7 years, then, natural selection caused the plants to evolve an earlier flowering time.

[Porterville]

I wish these NY’ers would stay the f* out of CA

[ClearCase_guy]

In the course of just 7 years, then, natural selection caused the plants to evolve an earlier flowering time.

The bar for what is classified as "evolution" is continually lowered. You know, there is another thread which says cats are going into heat earlier in the year -- but those scientists don't say this is "evolution in action" -- they say it's because of Global Warming.

Patheic excuse for science.

[Liberty1970]

In the Galapagos, if I recall correctly, they measured a 5% decrease in Finch beak length during a drought - and it then bounced back after the drought ended. This is cited as evidence that all life comes from a common ancestor solely based on the operation of natural processes. Kind of like claiming that your flat lawn proves the earth is flat.

If natural selection actually eliminated all the pre-drought genes for one variant then we would have... genetic impoverishment. The opposite of evolution. Instead we merely have, presumably, a minor fluctuation in gene frequencies. This isn't even evolution in the weak sense, and since there is no evidence of new genes arising to be selected during the drought, this whole study merely tracks shifts in the frequency of existing genes. No one would be wasting time or money on this sort of trivia were it not perceived as proving the earth is flat,, I mean, evolution...

[ClearCase_guy]

I completely agree. And, as I just pointed out on another thread, this is actually a current definition of evolution:

this whole study merely tracks shifts in the frequency of existing genes

Shifts in frequency = evolution. This, IMO, is a weak and pointless definition. I'm convinced that this definition has been chosen since it provides incontrovertible proof that "evolution is real". I say it's a joke.

[DManA]

Also, stress can affect the epi-genetic system with consequences for subsequent generations without ANY changes to the DNA.

[Soliton]

Patheic excuse for science.

It is clearly the case that you do not understand science.

[ClearCase_guy]

So — you agree that the apparent increase in the number of kitten IS due to Global Warming?

[Soliton]

So — you agree that the apparent increase in the number of kitten IS due to Global Warming?

Post the article and I'll let you know

[ClearCase_guy]

Global Warming Could be Causing a Kitten Boom, Experts Say
http://www.freerepublic.com/focus/f-news/2049922/posts

Seems like some scientists are saying that cats going into heat earlier in the year due to Global Warming.
Other scientists are saying that mustard plants are flowering earlier in the year due to evolution.

Some of these scientists are saying something foolish. Maybe both groups are.

[Soliton]

The people suggesting this aren’t scientists. The one scientist in the article actually says that it isn’t do to warming:”A cat’s cycle is based on day length, and day length isn’t changing,” said Christine Petersen, assistant professor at Iowa State University’s College of Veterinary Medicine. “Temperature’s going up a little, but the sexual cycle of the cat isn’t based on temperature.”.

The people making the claim are not mentioned as scientists or professors but executives in humane shelters. The Humane Society of America, is the cover organization for PETA.

[hellbender]

For many plants, including field mustard (a scrawny annual plant with little yellow flowers), a drought means a shorter growing season. A shorter growing season means that plants that flower earlier are more likely to leave seeds than plants that flower later — which are in danger of dying before they’ve finished reproducing.

I wonder how much the author actually knows about plant ecology. Mustards are alien annuals whose whole reproductive strategy is geared to rapid maturation and production of huge numbers of long-lived seeds, so they can take advantage of disturbed, early-succession environments. There is nothing new about "early flowering" by mustards. A wet field where other plants can compete more effectively might not be optimum for mustard seed formation; hence seeds from that field would not germinate as well in later years. In their rush to "see" evolution happening overnight, the author has ignored all other possibilities.