Laboratory Speciation in Helianthus Evolves a Native Species

furball4paws

[furball4paws]

Laboratory Speciation in Helianthus Evolves a Native Species

DNA examination of five species of Helianthus (H. annuus, H. petiolarus fallax, H. anomalus, H. paradoxus, and H. deserticola) suggested that H. annuus and H. petiolarus fallax are the evolutionary parents of the other three species (Rieseberg 1993, 1995, 1993). All five species are self-incompatible and fertile. Typically, H. annuus (the ancestor of the commercial sunflower) and H. petiolarus fallax form hybrids that are almost fully sterile. However, the few fertile hybrids, when subjected to sib-matings and back crossing regimes yield a new species that is fully fertile and cannot cross with either of the parental species. This new species is virtually identical to H. anomalus. The produced species is genetically isolated from the parents by chromosomal barriers. "Under laboratory conditions these changes are repeatable across independent experiments" (Niklas, p.64). The laboratory derived H. anomalus readily crosses with the native H. anomalus. Results indicate that H. deserticola and H. paradoxus may also have arisen via hybridization of H. annuus and H. petiolarus fallax. These two species have different synthetic capabilities from the parents and live in sandier and drier soils. Hybrid speciation may be common in plants where hybrids often form (see Gilia sp., Grant, 1966, Stebbins, 1959, Arnold, 1995), but is presumed rare in animals where hybrids are less common (however, see the minnow Gila seminuda, Bellini, 1994). Experiments to confirm the evolutionary parents of H. deserticola and H. paradoxus have not been performed. 1. Based on nuclear and chloroplast DNA analysis results, the Theory of Evolution predicts that H. annuus and H. pertiolarus fallax are evolutionary ancestors of H. anomalus, H. deserticola and H. paradoxus. 2. Hybrids of H. annuus and H. petiolarus fallax subjected to different regimes (at least 3) of back crossing and sib-matings, all converged into a new plant species with "nearly identical gene combinations" (Rieseberg) as the native species H. anomalus. This confirms the natural evolutionary parents of H. anomalus as predicted.

References 1. Arnold, J and S.A. Hodges. 1995. Are Natural Hybrids Fit or Unfit Relative to Their Parents? Trends Ecol. Evol. 10:67-71. 2. Bullini, L. 1994. Origin and Evolution of Animals by Hybrid Animal Species. Trends Ecol. Evol. 9:422-6. 3. Futuyma, D.J. 1998. Evolutionary Biology. 3rd. Edition, Sinauer Associates Inc., Sunderland, MA. 4. Grant, V. 1966. The Origin of a New Species of Gilia in a Hybridization Experiment. Genetics 54:1189-99. 5. Niklas, K.J. 1997. The Evolutionary Biology of Plants. Univ. Chicago Press, Chicago, IL. 6. Rieseberg, L.H. 1995. The Role of Hybridization in Evolution: Old Wine in New Skins. Amer. J. Bot. 82:944-53. 7. Rieseberg, L.H., and N.C. Ellstrand. 1993. What Can Molecular and Morphological Markers Tell Us About Plant Hybridization? Crit. Rev. Plant Sci. 12:213-41. 8. Rieseberg, L.H., B. Sinervo, C.R. Linden, M. Ungerer and D.M. Arias. 1996. Role of Gene Interactions in Hybrid Speciation: Evidence from Ancient and Experimental Hybrids. Science 272:741-44.A

Nice, neat, repeatable and meets all scientific criteria for a definitive experiment.

[furball4paws]

Got the wrong word - it's ovoviparous hatch inside

Oviparous - hatch outside

[Rudder]

Close, very close. It's actually "ovoviviparous."

[furball4paws]

I stand corrected - and getting into the category of a tongue twister, too.

Doesn't look like the fishing's too good today. Now if we just had a Man/Dog thing.

[stremba]

Why do you have to go and confuse this issue with all that science stuff? This isn't about science; God did it!!! /creationist mode

[furball4paws]

I am never sure whether I should bite or smile at these things. Since I started it I felt smiling was better, but with this guy I don't think he'd be satisfied with anything other than pulling the thread.

So - here's some primordial ooze in his eye.

[Junior]

It's Just a Theory
(with apologies to Blue Oyster Cult)

Darwin's time has come
Evolution now is gone
Creos don't like the theory
We're certain it's just plain wrong.
They can be like we are

Come on creos ... It's just a theory
No need to listen ... It's just a theory
Darwin's on the outs ... It's just a theory
All his links are missin'...

S. J. Gould is done
P.E. now is gone
Behe, Miller, Hovind
Will now tell us how it's done
Behe, Miller, Hovind...

Americans believe the creos ... Behe, Miller, Hovind
Americans believe the creos ... Tell us how it's done
And more are joining us everyday ... You can be like we are

Come on creos ... It's just a theory
No need to listen ... It's just a theory
Darwin's on the outs ... It's just a theory
All his links are missin'...

Evolutionary biology
Was here but now it's gone
We'll replace it with ID
Regardless if it's really wrong
We regard it as a kind of tool
It's just a wedge to get God in school
To see how many we can fool
Saying, "join the creos..."

Come on creos ... And then they came
Flocked in droves ... We ain't no slime
Turned the clock backward in time
You'll become like we are
No need for research
You'll become like we are

Come on creos ... It's just a theory

[b_sharp]

Good stuff. Thanks for posting it.

[b_sharp]

"I douby that too many creationoids will come out for this "

Don't be too sure, they'll find something in there that helps their cause, at least in their minds.

Besides, it's still just a flower. It didn't evolve into a Lama or anything.

[b_sharp]

"Plant hybridization hardly proves evolution - it is unique to plant "design". Stop wasting bandwidth with this nonsense. This has been debated to death without resolution. All it does is to start endless fights that don't accomplish anything."

Of course, but everything is unique to "design". In otherwords, goddidit.

No matter what is shown to speciate it will never show the veracity of evolution. Is this close to the truth from your view?

[b_sharp]

Too late. They beat you to it.

[b_sharp]

"But even bullfrogs don't come out looking like bullfrogs. They look like -- fish. At least for a time.'

But they taste like chicken.

[furball4paws]

"H. anomalus, H. deserticola and H. paradoxus hybrids since God created them."

Sorry to disappoint you, but H. anomalus and H. paradoxus and H. deserticola are not hybrids. They are separate species, by anyone's definition of the word.

[furball4paws]

If an atheist is a Liberal and a scientist is a Communist - whate is an atheist scientist. I mean if two negatives make a positive we must have ----- SUPER DUDE!!

[WildHorseCrash]

Wrong definition. When dealing with creationists, "microevolution" is the stuff that they have to admit has occured because it has been observed, and "macroevolution" is the "stuff that will never happen, ever" until it does happen, at which point that specific event -- and nothing else -- suddenly falls into the category of "microevolution" (with no apologies for claiming that it was impossible in the first place).

...because we are at war with Eastasia. We've always been at war with Eastasia.

[b_sharp]

I'm not sure whether I should thank you or simply take my bows. Hmmm. Maybe I'll just give up my intellect and go creationist. Nope. Too scary.

[longshadow]

Is there any chance that this thread could be put back into the forum where it began? This is a good science thread, and all the others like it are posted in, and remain in, the "news/activism" forum.

I second the motion. I also note the flaming was started by someone who doesn't like these threads.

[FourtySeven]

Bumpity!

[FourtySeven]

You know, looking over this article for my own reference (possilbe, in the future) of it, I don't see the exact reference. Where was it published, when, etc? Or am I missing something?

Thanks,

[UnbelievingScumOnTheOtherSide]

>Sorry to disappoint you, but H. anomalus and H. paradoxus and H. deserticola are not hybrids. They are separate species, by anyone's definition of the word.

You might want to read the article you posted. It was somewhat interesting. [Evoids can read, can't they?]

"The laboratory derived H. anomalus readily crosses with the native H. anomalus. Results indicate that H. deserticola and H. paradoxus may also have arisen via hybridization of H. annuus and H. petiolarus fallax."

[js1138]

What's your point?