Wirt Wrote:
>None of these attributes serve the plant.
>These are qualities that only serve the human masters that grow highly
>selected cultivars, and all of these qualities would rapidly disappear if the
>plants were released to the wild again.

I would argue that these changes have served this plant (gene-line) very well as there is more cotton grown now than ever before in 'the wild'.  One might also observe that largely there is no 'wild' to return to for these plant so it was fortuitous that they were flexible enough to remain interesting to us rather than simply be paved over, frozen (if you believe Denys) or baked/flooded (if you believe AGW).  Regardless of what the future holds, having been much more widely dispersed by human activities they arguably have a better chance of surviving whatever is thrown at them (as long as we didn't inadvertently remove useful information from their genes along the way).

Then again maybe the cotton plants planned all of this along with the corn ?  Interesting talk from the TED conference:

"http://www.ted.com/index.php/talks/view/id/214

. . . What if human consciousness isn't the end-all and be-all of Darwinism? What if we are all just pawns in corn's clever strategy game, the ultimate prize of which is world domination? Author Michael Pollan asks us to see things from a plant's-eye view -- to consider the possibility that nature isn't opposed to culture, that biochemistry rivals intellect as a survival tool. By merely shifting our perspective, he argues, we can heal the Earth. Who's the more sophisticated species now?"

Jim

-----Original Message-----
From: HP-3000 Systems Discussion [mailto:[log in to unmask]] On Behalf Of Wirt Atmar
Sent: Saturday, March 15, 2008 12:54 PM
To: [log in to unmask]
Subject: Re: [HP3000-L] OT: biology question

I wrote earlier:

> As to the "purpose" of a cotton boll, cotton is a commercial crop of high
> agronomic importance, and as has been said, been selectively bred for
> certain
> genetic traits for more than 6000 years now. In this context, to ask "what
> purpose does the cotton boll serve the plant" is the equivalent of asking "
> what purpose does a poodle haircut serve the dog?"

Reading that paragraph over, it may have come across as harsher than I
meant it.

The modern cotton boll has been bred for long-staple, crystalline white, high-
density fiber, while greatly reducing the mammalian toxicity of the plant seeds,
while simultaneously making the plant intolerant to specific commercial
herbicides ("Round-up Ready"). None of these attributes serve the plant.
These are qualities that only serve the human masters that grow highly
selected cultivars, and all of these qualities would rapidly disappear if the
plants were released to the wild again.

But the cotton boll does have purposeful, evolutionary value to the plant, just
as the hair of a poodle has similar enormous value to the dog, but not in its
human-dictated configuration, nor for any human-valued reason.

All fruits in flowering plants serve the purpose of seed dispersal, but there is
no single, royal road to that end. Fruits can explode, fly, parachute, become
ensnared on the coats of animals, drift on flowing streams or be eaten by
animals as their specifically chosen method of dispersal. Whichever method is
chosen, the phylogenetic lineage optimizes its fruits for that purpose over
evolutionary time.

Some of these methods are shown here:

   http://www.cas.vanderbilt.edu/bioimages/pages/fruit-seed-dispersal.htm

Quite often the method of seed dispersal employed by a specific plant species
requires the co-evolution with specific animals, and when those animals are
locally extincted, the plants are put at risk. Look particularly at the fruit of the
Osage orange on the page above. It's giant structure is believed to be an
attractive adaptation to dispersal by Pleistocene megafauna (mammoths, giant
sloths, etc.) that were killed off by the arrival of humans in North America
13,000 years ago, and the plant is therefore at some heightened risk of long-
term survival now.

But the more important picture is this one:

http://www.hear.org/starr/hiplants/images/600max/html/starr_011104_0049_go
ssypium_tomentosum.htm

This is an image of the opened boll of a wild species of cotton in Hawaii. The
fibrous lint, when released by the plant, will carry the plant's seeds in the
wind, or at least along the ground, much like a dandelion's, so that the people
who suggested that purpose were on the right track, and that's the statement
that I wanted to correct.

Also note that the lint is brown. Wild cotton lint occurs in brown, black, red,
green, as well as a variety of whitish yellow colors. These species have been
banned from the fields of commercial growers simply for fear of genetically
contaminating the very white varieties that have been bred, but color, if it has
any selective value at all in its original context, must have been a very minor
consideration for purposes of seed dispersal.

Wirt Atmar

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