Tuatara

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OilIsMastery

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Evolving or not?

The tuatara has remained virtually unchanged over the past 140 million years.
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"What we found is that the tuatara has the highest molecular evolutionary rate that anyone has measured," Professor Lambert says.
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So let me get this straight, the fastest evolving animal known to man hasn't changed in the last 140 million years? WTF?
 
Mutation in noncoding regions, most likely. You can look the same so long as the germinal line isn't heavily mutated.
 
Yep. All things evolve, mathematically. If you're thinking desent with modification, most things do that but not everything.
 
Just imagine that there are trillions of cosmic rays hitting the Earth, going through things and altering those things at times. Not everything gets hit in a way to change the DNA sequencing but sometimes they do and mutations are made within that organism. It is by chance this happens and it could one day cause the "evolution" of any living this as well as the things own chemicals could to itself as well.
 
Mmm, nothing of any morphological significance, anyway. But it should be noted that 'allele' can be a relative thing. It doesn't need to refer to some functional allele even though this is the normal usage since we're all obsessed with fitness and quantitative genetic structure. It can refer to single nucleotide polymorphisms (SNPs) at marker genes or just random locations in the genome; in fact, such neutral or presumably neutral polymorphisms can be used to track the inheritance of mutations at functional loci (see "Quantitative trait locus" on Wiki).
 
GeoffP said:
Mmm, nothing of any morphological significance, anyway.
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So by the text book definition it isn't evolving.

GeoffP said:
(see "Quantitative trait locus" on Wiki).
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There has been no change in the phenotype in over 140 million years. It seems to me that is a very serious problem for the evolution hypothesis and it needs to be addressed in a scientific way, i.e. based on observation and logic.
 
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August 7, 2008

Lizard love: 110-year dinosaur descendant to become daddy

(CNN) -- At well over 100 years old and showing no interest in sex for over four decades, Henry is on his way to becoming a dad.

Henry is a tuatara, a rare lizard-like creature that descended from dinosaurs. The tuatara has been endangered since the 1890s, and it's only found on a handful of New Zealand's offshore islands.

At about 110 years old, Henry is the oldest tuatara ever to mate at Southland Museum on the country's South Island.

"I had given up on old Henry," said curator Lindsay Hazley.

He kept Henry in "solitary confinement" because the animal not only showed no interest in females but attacked them when they were looking to mate.

The beginning of Henry's libido rebound came in 2002, when veterinarians realized that a lump in the animal's nether regions was a cancerous tumor. They removed it and, over the next few years, his attitude began to change.

"I say that he had a personality transplant at the same time," Hazley said Thursday. "If I had a tumor underneath my [genitals], when girls were passing by, I'd be a very grumpy boy too."

In March, Henry mated with Mildred, whose age is estimated between 70 and 80. Last month, she laid 12 fertile eggs, 11 of which remain healthy.

Healthy hatchlings would be a boost for the tuatara, who are the only living descendants of the order Sphenodontian, which flourished 200 million years ago.

They max out at about 32 inches from head to tail -- much smaller than their ancestors -- but the spiny ridges along their back suggest their prehistoric parentage.

The word "tuatara" is derived from a Maori word meaning "spiny back." In Maori legend, they are messengers of Whiro, the god of death and disaster, and they were featured on one side of a New Zealand five-cent coin that was phased out in 2006.

Hazley estimated that as many as 40,000 tuataras live on one of New Zealand's tiny, outlying islands, with much smaller populations on several others.

There are 51 at Southland Museum, where Hazley, who has cared for tuataras for the past 35 years, has been breeding them. He said he hopes Henry and Mildred's hatchlings will be the latest success.

"I'm excited, but I don't want to get too excited because Mother Nature's always got the power to ground you," he said. "I really don't like counting the chickens before they hatch, but each day that goes by, I'm becoming more confident they're going to be fine."

As for Henry, his best years as a ladies' man may be ahead of him. At 110 years old, he's just hitting middle age for a species that can live well past 200.

"I think he'll be at these girls long after I'm gone," Hazley said.
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Narration:
Research revealed Tuatara were now confined to just seven viable islands, around New Zealand.

And even here in their stronghold of Stephens Island, which contains most of the world’s tuatara, they were vulnerable. Island after island was falling to rats.

Nikki Nelson: If rats get to an island where tuatara are you know they can just wipe out populations. The latest extinction was 1986.

Jonica Newby, Reporter: 86?

Nikki Nelson: Yeah, A whole tuatara population just wiped out.

Narration:
Then, in 1990, scientific investigations of the tuatara delivered another shock.

Through DNA analysis, the team discovered there were not one but two species of tuatara.

And the rarest was found only on this tiny rocky outcrop known as Brothers island.

Professor Charles Daugherty led that research. He realised it meant the tuatara was a lot more endangered than they’d thought.

Charles Daugherty: We knew from the field work that we had done that there were only four hundred animals left in that population and of course that’s a terrible discovery to know that you’ve got what may be the rarest reptile species in the world.

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This was crisis point. If they were going to save the Tuatara, it was time to pull out all stops.

Their ambitious plan was to introduce the tuatara to other rat free islands. But first they had to find out if they could raise them in captivity.

Eggs, collected painstakingly over months, were delivered to Wellington to see if they could be brought to life.

Nikki Nelson: So this is where they are – eggs.

Jonica Newby, Reporter: Incubators?

Narration:
In the lab, they discovered that the sex of the embryo was determined by temperature.

Nikki Nelson: They’re beautiful eggs, aren’t they.

Narration:
Many reptiles show this, but the tuatara was particularly temperature sensitive. Just one degree celcius meant the difference between the egg developing into a boy or a girl.

Nikki Nelson: A hundred percent females at twenty one degrees, a hundred percent males at 22 degrees you know.

Jonica Newby, Reporter: Is that unusually narrow?
Nikki Nelson: It’s very narrow.
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OilIsMastery said:
So by the text book definition it isn't evolving.
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By the textbook (mathematical) definition, it is. By the popular definition ("descent with modification"), it isn't.

There has been no change in the phenotype in over 140 million years. It seems to me that is a very serious problem for the evolution hypothesis and it needs to be addressed in a scientific way, i.e. based on observation and logic.
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Why? What's changed so drastically about their islands? There were ones on the mainland; they died out, didn't adapt. I think the problem is solved.

OIM, evolutionary theory doesn't require that an organism change. So long as it's able to survive in the form it has, it survives. If there are mutant or variant types - some deleterious, some not - they might make it or not. If the environment changes to favour those mutants, they survive and the original type persists. This is evolution, in the popular definition. Tell me: why are they obliged to change?
 
On a side note, I bloody love the tuatara. Amazing little organism. You know these little buggers are still moving about at 20-25C? They don't mind the cold so much. Amazing animals.
 
OilIsMastery said:
So what alleles have changed in the sphenodon/tuatara?
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How should I know? I'm not studying them. You asked a question, I just answered it.
* Allele frequency can change without the organism's phenotype changing. Like pesticide resistant insects, look the same but their allele frequencies for pesticide resistance have changed.
 
GeoffP said:
On a side note, I bloody love the tuatara. Amazing little organism. You know these little buggers are still moving about at 20-25C? They don't mind the cold so much. Amazing animals.
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Too bad they're endangered; I would love to have one as a pet...:D
 
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They are brilliant, aren't they? I did a report on them once. So amazing.

I went to the San Diego Zoo - my one and only chance to see them, happened to be in town....

...exhibit was closed.

:bawl:
 
GeoffP said:
They are brilliant, aren't they? I did a report on them once. So amazing.

I went to the San Diego Zoo - my one and only chance to see them, happened to be in town....

...exhibit was closed.

:bawl:
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For sure they are. Wow. Next time I'm in San Diego I will definitely have to visit them. Simply amazing.
 
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