Hyper Evolution Possible?

Dr Mabuse

Dr Mabuse

Percipient Thaumaturgist
Registered Senior Member
July 29, 2009
Is Hyper Evolution Possible? A Galaxy Classic

Think it takes thousands or even millions of years for animals to evolve significantly new traits? Think again. New research lends just a touch of credibility to the idea behind the popular sci-fi TV series Heroes, which portrays certain humans as having quickly evolved new astounding traits in response to increasingly tumultuous environmental pressures.

In 1971 biologists moved 5 adult pairs of Italian wall lizards from their island home of Pod Kopiste, in the South Adriatic Sea, and introduced them to the neighboring island of Pod Mrcaru. An international team of researchers discovered that introducing these small, green-backed lizards, Podarcis sicula, to a new environment caused them to undergo shockingly fast and large-scale evolutionary changes.

Researchers returned to the islands twice a year for three years, in the spring and summer of 2004, 2005 and 2006. Captured lizards were transported to a field laboratory and measured for snout-vent length, head dimensions and body mass. Tail clips taken for DNA analysis confirmed that the Pod Mrcaru lizards were genetically identical to the source population on Pod Kopiste. In other words, there is no doubt that these lizards are the offspring of the 1971 transplant. The results of the study were recently published in Proceedings of the National Academy of Sciences.

The lizards evolved entirely new digestive system features to cope with dietary changes, evolved bigger heads and also ceased to defend territories—an instinct once very integral to the species behavior back on their original home territory.

“Striking differences in head size and shape, increased bite strength and the development of new structures in the lizard’s digestive tracts were noted after only 36 years, which is an extremely short time scale,” remarks Duncan Irschick, a professor of biology at the University of Massachusetts Amherst.

Observed changes in head morphology were caused by adaptation to a different food source explains Irschick. The lizards on the barren island of Pod Kopiste were well-suited to catching mobile prey, feasting mainly on insects. Life on Pod Mrcaru, where they had never lived before, offered them an abundant supply of plant foods, including the leaves and stems from native shrubs. Analysis of the stomach contents of lizards on Pod Mrcaru showed that their diet included up to two-thirds plants, depending on the season, a large increase over the population of Pod Kopiste.

“As a result, individuals on Pod Mrcaru have heads that are longer, wider and taller than those on Pod Kopiste, which translates into a big increase in bite force,” says Irschick. “Because plants are tough and fibrous, high bite forces allow the lizards to crop smaller pieces from plants, which can help them break down the indigestible cell walls.”

Examination of the lizard’s digestive tracts revealed something even more surprising. Eating more plants caused the development of new structures called cecal valves, designed to slow the passage of food by creating fermentation chambers in the gut, where microbes can break down the difficult to digest portion of plants. Cecal valves, which were found in hatchlings, juveniles and adults on Pod Mrcaru, have never been reported for this species, including the source population on Pod Kopiste.

“These structures actually occur in less than 1 percent of all known species of scaled reptiles,” says Irschick. “Our data shows that evolution of novel structures can occur on extremely short time scales. Cecal valve evolution probably went hand-in-hand with a novel association between the lizards on Pod Mrcaru and microorganisms called nematodes that break down cellulose, which were found in their hindguts.”

Change in diet also affected the population density and social structure of the Pod Mrcaru population. Because plants provide a larger and more predictable food supply, there were more lizards in a given area on Pod Mrcaru. Food was obtained through browsing rather than the active pursuit of prey, and the lizards had given up defending territories.

“What is unique about this finding is that rapid evolution can affect not only the structure and function of a species, but also influence behavioral ecology and natural history,” says Irschick.

So next time you see Hayden Panettiere on TV running around in her cheer skirt regenerating her limbs, just think how the premise may be just slightly less crazy that you previously suspected.

Posted by Rebecca Sato.

Study Source: University of Massachusetts Amherst
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Interesting article. How quickly CAN life evolve to meet new conditions?
 
In the face of intense environmental pressures, species either evolve quickly or go extinct. Both have happened with regularity. See Gould's punctuated equilibrium theory of evolution.
 
Evolution is just a piece of non sense. How come humans did not become pigs or horses...?!. hahahah.

Mod note: Stupidity or trolling, either way it’s an infraction.

NOTE : I think I gave my honest oipinion .
Both Big bang and evolution are mere theories and not 100% true scientific data .
I have no idea why this warning or whtever .
If we can not give our opinions then why debate at all...???!!!!.
If you ban me I am not going to die.
hahahahahahah
 
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“Striking differences in head size and shape, increased bite strength and the development of new structures in the lizard’s digestive tracts were noted after only 36 years, which is an extremely short time scale,” remarks Duncan Irschick, a professor of biology at the University of Massachusetts Amherst.
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We’ve known for a long time that evolution can proceed very quickly, but 36 years is amazingly quick for a vertebrate such as a lizard. :eek:

http://www.sciforums.com/showthread.php?p=980661#post980661
 
Evolution is quite amazing. I am stuyding microbiology, and with microbes these changes are even quicker. With viruses, changes are so quick that drugs are often unable to cope.

An example is HIV. When you start giving a HIV+ person drugs, the virus evolves within a matter of days to completely bypass the anti-viral effects.

The fact that changes can be this quick in macroscopic creatures is just another proof of the complexity and practicality of evolution and genomics.
 
This certainly defies my understanding about how evolution works. I always understood it to be a slow gradual process over thousands of years, but evidently this is not so. What amazes me most is at the genetic level the rapid appearance of adaptive mutations that allow this kind of physical transformation to occur. I thought mutations were a rare occurrence, but evidently that is not the case, and when they prove beneficial in a novel environment they can quickly transform the genome of a species.
 
Salamander7 said:
I always understood it to be a slow gradual process over thousands of years,
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I think this is because our recorded history (fossils and so forth) are so limited as to be separated by sometimes thousands of years. Looking at our past evidence paints a picture of very long, gradual change.

But in fact, even between months there are constant fluctuations.

Check out the book "The Beak of the Finch" for hardcore evolutionary data.

http://www.ventrella.com/Alife/Cells/GlidersAndRiders/Cells.html

Run that simulation, and look at the graph. It shoots back and forth most of the time. From what I remember, the data from the Galapagos does the same thing.
 
Tail clips taken for DNA analysis confirmed that the Pod Mrcaru lizards were genetically identical to the source population on Pod Kopiste...
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Uh...obviously not genetically identical, given the entire point of the article...
 
Nasor said:
Uh...obviously not genetically identical, given the entire point of the article...
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Yes, good man! :thumbsup: I spotted this yesterday and started writing a reply but my work intervened and I never got back to it.

Obviously the modern day descendants cannot be genetically identical, even if these lizards are employing some form of parthenogenetic reproduction. As far as I know, all instances of parthenogenesis seen in vertebrates, such as reptiles, involve meiosis and, hence, produce shuffling of genetic sequences through meiotic recombination.

I attribute the confusing statement to the usual scientific inaccuracy that we see in mainstream mass media science reporting (or in this case, a personal blog). I haven’t read the original publication, but I would make a solid bet that the statement regarding the Pod Mrcaru lizards being “genetically identical” to the source population refers to the results of genotypic/population analysis techniques, such as microsatellite analysis or mitochondrial gene analysis or rRNA sequences, and not the whole genome.
 
Xylene said:
Even so, what's 36 years in lizard generations? How soon do they start breeding after birth, and how much genetic change could take place over that number of generations?
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I think it ranges from smaller lizards like Anole being a few years to iguanas reaching 10. In the wild you can cut those numbers in half and maybe in half again.

Also I think they mate seasonally and usually have like 10 to 20 rubbery eggs at a time. I would estimate they could start producing eggs in their first year. But the last two sentences are just speculation
 
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