unassuming winner of evolution

[NosePicker]

We go about busy lives at work, shopping, and playing blissfully unaware that there is literally evolution happening in a neglected lawn. There is a plant becoming a new species growing there.
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The formal name of the plant is Crepis sancta. We know them to be dandelions.
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To adapt and make sure more of it's seedlings survive, it is switching to heavier seeds that fall to close by dirt rather than the wind driven light seeds that will most likely land on tarmac or cement. This change took about 12 generations, or five years as the Human lives.
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Is this risky? Yes. The new plants evolving can be heading toward an evolutionary dead end. That is a risk many life forms before them took, and many after will take.
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This isn't the first course of evolution this plant quietly took underfoot. The common dandelion used to be a long stemmed, tall species. That put it's flowers and seedpods at risk of lawn mowers on well manicured lawns. The tall dandelion is no longer common. It now grows only in neglected areas where a lawnmower won't menace.
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The lawn now sports ground hugging dandelions that are seldom taller than the grass itself, out of range of a lawnmowers blades. To eliminate now, the lawn owner has to do a determined pull at the roots of this pernicious little unassuming winner of evolution.
*

[hhEb09'1]

We're growing free-range dandelions here. For salads, and wine.

[Gillianren]

The tall dandelion is no longer common. It now grows only in neglected areas where a lawnmower won't menace.

Not around here.

[redshifter]

This isn't the first course of evolution this plant quietly took underfoot. The common dandelion used to be a long stemmed, tall species. That put it's flowers and seedpods at risk of lawn mowers on well manicured lawns. The tall dandelion is no longer common. It now grows only in neglected areas where a lawnmower won't menace.
*
The lawn now sports ground hugging dandelions that are seldom taller than the grass itself, out of range of a lawnmowers blades. To eliminate now, the lawn owner has to do a determined pull at the roots of this pernicious little unassuming winner of evolution.
*

Apparantly the dandelions in my yard didn't get the memo...

[captain swoop]

Tall Dandelions are the same as the short ones. Stop cutting your lawn and see how tall they grow.

[beskeptical]

My dogs love to help me keep the Dandelions down. I often pick off the seed pods before the wind gets them (totally a wasted endeavor, I'm sure) and whenever I do my dogs happily race to the flowers and bite them off. It's a very cute behavior, like a little kid copying something mommy does.

I can attest to the observed ground huggers though. But I'm not so sure it's a genetic change or simply an existing variation that is triggered when needed.

[captain swoop]

Other plants are the same. My lawn has Daisies in it, they stay tight down in the grass if you keep mowing but grow tall if you leave it.

[mugaliens]

Other plants are the same. My lawn has Daisies in it, they stay tight down in the grass if you keep mowing but grow tall if you leave it.

We used to use daisies for target practice...

[BigDon]

I was going to mention topiaries of which I made several. From simple geometric shapes to a couple of animals (elephant and horse).

It takes advantage of a plant's adaptation to browsing animals. Nibble the sides, the plant grows taller, nibble the top the plant grows wider, due to the different growth hormones put out by side branchs and the upper tips.

[Jay200MPH]

Lawnmowering tall dandylions may kill the individual plants, but it also spreads the seeds far and wide along with a batch of fresh mulch for fertiliser. It's a huge help to the species as a whole.

- J

[Ivan Viehoff]

The formal name of the plant is Crepis sancta. We know them to be dandelions.

Dandelions are properly Taraxacum officinale, and more generally for the Taraxacum genus. Crepis is another division of the Asteraceae, known as hawksbeards. Though there may be a colloquial tendency to refer to any rosette-forming yellow-flowered member of the Asteraceae as a dandelion. As far as I am aware, C. sancta is restricted to the SE Mediterranean, especially Israel, and I can't find any info that it has become a weed elsewhere.

Taraxacum mostly reproduce by apomixis, ie, without pollination. So their ability to evolve by the Darwinian process is limited. Apparently at least a temporarily successful, but risky, strategy.

By chance yesterday I came across a reference to the Russian Dandelion. That rejoices in the name of T. kok-saghyz, which had my wife chortling away for a while. It was formerly cultivated, because the latex in the roots is an excellent source of rubber, and very good yields were obtained. But it has been replaced by synthetic rubbers.

[BigDon]

Thank you Ivan.

I did not know that at all about the rubber.

[Gillianren]

I do remember from childhood experimentation that even whatever varieties are common in Los Angeles County (there were clearly more than one) had very thick sap. I'm fascinated but not entirely surprised to learn that there's one with thick-enough sap for rubber production.

[tlbs101]

So, should we name this new species Taraxacum officinale aporia?

.

[BigDon]

I think if Np is really interested in unique forced evolution traits he should check out the changes forced on some of our other pests.

Where I live it has a long tradition of growing decorative plants and flowers until the land got too valuable for greenhouses in the 90's. Not being a food crop you can nerve gas the crap out them as long as they are safe by selling time. ~two weeks after last dose for most commercial pesticides, strong carbamates two months, (no touching!).

The whitefly, Aleyrodidae species, in my area have unique nervious systems due to adapting to the early pesticides used on them. I read a report that stated some local strain's nervous systems are now unique in the animal kingdom.

Though details are lacking, they are completely immune to both carbamate AND organophosphate poisoning. Seems they decided that whole use of cholinergic chemicals to run their nervous systems was getting them nowhere and opted for something else, though what they use instead I'm clueless.

Raid, even the full strength, oh-my-lord, roach Raid only kills them if you spray them enough to mechanically drown them. Same with neem oil.

I'm sure Mr.'s Brak, Hutchenson and Paracelsus will probably want to raise further questions about this. (I'll look for my sources as this is a rather strong claim.)

[farmerjumperdon]

I use a pre-emergent. They can adapt there little backsides off; won't give them any advantage in my yard.

[Nick Theodorakis]

...
Though details are lacking, they are completely immune to both carbamate AND organophosphate poisoning. Seems they decided that whole use of cholinergic chemicals to run their nervous systems was getting them nowhere and opted for something else, though what they use instead I'm clueless.
...

A quick search on the scientific literature indicates organophosphate (OP) resistant bugs still use cholinergic neurotransmitters, but they can acquire resistance to OPs by either (1) mutation of the acetylcholinesterase gene such that it is no longer inhibited by OPs, or (2) increased levels or activities of enzymes that can break down OPs. Similar effects are observed for carbamate resistance.

Here is a review (but you may need to be at a subscribing institution to read it).

Insecticide Resistance in Insect Vectors of Human Disease
Janet Hemingway and Hilary Ranson
Annual Review of Entomology
Vol. 45: 371-391 (Volume publication date January 2000)
(doi:10.1146/annurev.ento.45.1.371)

Nick

[BigDon]

Thank you Nick,

I have decided to try and keep the hyperbole to a minimum in my posts, as it confuses some of the more literal thinking people, but it creeps in by force of habit.

Thank you very much for the information and clarification.

Farmer, what do you use on whitefly? I would really apreciate that information. (Getting the flowerbeds ready shortly.)

[Nick Theodorakis]

Hyperbole is the single greatest threat to civilization ever devised!

Nick

[farmerjumperdon]

Thank you Nick,

I have decided to try and keep the hyperbole to a minimum in my posts, as it confuses some of the more literal thinking people, but it creeps in by force of habit.

Thank you very much for the information and clarification.

Farmer, what do you use on whitefly? I would really apreciate that information. (Getting the flowerbeds ready shortly.)

The only insecticide I use is Malathion; and I only use it when the going gets tough. I'm not against sharing some produce with nature's little crawly things, but swing into action when they threaten to consume the entire crop. In the 12 running years I've been doing serious gardening I have never treated the berry patches, treated the vegetable garden only once, and have treated the fruit trees 4 or 5 times.

The bugs really seem attracted to my apples more than anything else and can ruin the whole crop in no time, so I am quick to treat them there at the early sign of large numbers of bugs. I had a couple seasons where I learned the hard way by delaying, thinking they would pass and I'd still get plenty for us. Almost no apples those years unless you didn't mind eating around the bugholes.