Evolution Breakthrough Challenged

(Discover)  The bones of our ancestors do not speak across time with ultimate clarity. The fossils with which scientists reconstruct our family tree are often fragments that offer hints and clues to where we came from. So it comes as no surprise when, as part of the flow of science, researchers offer counter-interpretations to even the most famous of finds.

That's what happening to Ardi.

Last October Ardipithecus ramidus hit the main stage when, after 17 years of study, a large team led by paleoanthropologist Tim White published its work in the journal Science. The 4.4-million-year-old find shakes up our understanding of our own history, White said-primarily the story of how and when we learned to walk.

Ardi cast doubt on the widely accepted view that our ancestors became bipeds because they left the forest and entered a flatland savanna habitat that demanded it. But Ardi appeared to be a kind of hybrid, comfortable in the trees and on the ground. And, White said, analysis of the site where the fossil was found indicated that Ardi lived in a woodland habitat. If it's true that early humans walked in the woods, then the "savanna hypothesis" would be swept away.

But not so fast. In today's edition of Science, two teams of scientists respond (1, 2) with doubts about the story of Ardi.

According to The New York Times: "The question of Ardi's habitat was raised by Thure E. Cerling, a geochemist at the University of Utah, and seven other geologists and anthropologists. They said they used the White team's own data for soils and silica from ancient plants, and found it did not support an interpretation that Ardi lived in thick woods. Instead, Dr. Cerling's group said, "We find the environmental context of Ar. ramidus at Aramis to be represented by what is commonly referred to as tree- or bush-savanna, with 25 percent or less woody canopy cover."

The second paper questions whether Ardi is really an early human at all, rather than a member of the chimpanzee line. From Nature: Ardi's age is so close to that divergence date that no unequivocal determination can be made about whether she is in the ape or human lineage, says [primatologist Esteban] Sarmiento, who conducts research from home in East Brunswick, New Jersey. But White and co-authors disagree. In their response, the group says Sarmiento's "tortuous, nonparsimonius evolutionary pathways" are not supported by many of the fossil's characteristics.

White and colleagues issued responses to both questions (1, 2) in the same issue, and struck back in the press, too.

If Ardi were really ancestral to chimps, certain features of its teeth, pelvis, and skull would have had to later evolve back to their more ape-like conditions, an "evolutionary reversal that's highly unlikely," White said in an interview.

White is sticking to his guns regarding Ardi's habitat, too. While it's true that the fossil record seems to show grasses where Ardi lived, there are also many fossils of forest-dwelling animals that suggest a wooded area, he argues.

By Andrew Moseman
Reprinted with permission from Discover

[rf35]

I like seeing science in action. This is what it's all about; building a hypothesis, developing it into theory, meeting the challenges to it. Science allows for changes to a theory as new evidence is discovered.

Science molds its conclusions to fit new discoveries. Religion trys to mold new discoveries to fit a predetermined conclusion.

[jankebenzone]

by jaykay3141 May 29, 2010 6:29 PM EDT
I don't post with the intent to promote my lexicographical skills, but rather to present commonsense to all to often fallacious theories such as evolution being factual.
Your theory of bacteria "evolving" to become drug resistant is one of these fallacious theories. Think! why has most bacterial and virus based illness and diseases remained unchanged till the introduction of medicines and drugs. Why do people not "evolve" to be resistant to various health problems such as the cold and flu? The ones who seem to never get a cold or flu have'nt "evolved" to a stronger species, but have more healthy immune systems. Thats fact! not ever changing theory.
How do I know? Mostly because I can think for and on my own and not just thinking what the general populace or junk science presents.

[j_mcdonald-2009]

But humans HAVE evolved to be resistant to diseases. Those who weren't resistant died and had fewer children. Have you ever studied the relationship of sickle-cell anemia to malaria resistance? Also, note that populations evolve, not individuals.

[j_mcdonald-2009]

"Why has most bacterial and virus based illness and diseases remained unchanged till the introduction of medicines and drugs."

They did change--medicines and drugs provided enormous selective pressure for them to evolve even faster.

[ddog88]

I iz cornfused, iz dat der a a pikture of Jeezus or Moohamds skeeliton. Cuz I thinks dat im posed to be gittin mad.

[KeithDrippingSprings]

I am glad I got here before too many Christians came and made the comment section silly. There is Dogma in science, as much as in religion. Their positions are defended from different criteria. Try getting your doctorate by writing something the head of the department doesn't agree with and you will know the "truth" as seen in academia.

[formrusmcsgt]

The second paper questions whether Ardi is really an early human at all, rather than a member of the chimpanzee line.
---
The challnge process itself is what makes science infinitly superior to dogma.

[jankebenzone]

by chris_weiss May 28, 2010 6:16 PM EDT
Did you know that the DNA stucture of most animals, seven large warm blooded fish ie. gray whale, ls very close to the human structure?
Its because were all made basicly of the same materials yet different. Take buidings for instance, there are all made of cement, wood, steel,ect., but the differences in design and funtion is vastly different. Bacteria and virus don't evolve to be drug resistant, their imine systen adapts to fight off invaders, just like human imune systems will attack invaders and build up a resistance to them. That's the beuty and wonder of God's creation. Sorry, but its you and other atheists/evolutionists that need to do more homework and ignore less facts.

[j_mcdonald-2009]

Here's a suggestion--take a biology course. You don't have a clue what you are babbling about.

[jaykay3141]

"Bacteria and virus [sic] don't evolve to be drug resistant, their imine [sic] systen [sic] adapts to fight off invaders ..."

The "validity" of that statement is matched only by the quality of its orthography. Drug resistance doesn't arise from a single generation of bacteria changing themselves internally in response to external challenges by a drug. Normal variations mean that any group of organisms will have some members in each generation who are slightly better (or worse) than others in some characteristic. Among bacteria that includes drug resistance, so if you take an antibiotic for an infection, it'll take longer to kill some of the "bugs" than others.

If all of the bacteria in a colony aren't killed those that remain have a higher likelihood of being more drug-resistant. The next generation will tend to inherit a higher level of resistance, and so on. The mechanism isn't adaptation of a single bacterium or single generation of bacteria, but rather changes among many members throughout many generations - i.e. EVOLUTION.

[jankebenzone]

Well. well, just more evidence for the growing stack of evidence that the theory of evolution is bogus. But of course the knowledgable knew that long ago.

[chris_weiss]

We see evidence for the core components of evolution today without relying on fossils, including speciation, increases in "information" in DNA, and natural selection. Look at drug resistant bacteria, mutating corona viruses, etc. The evidence for evolution is overwhelming. It still doesn't answer the question of where did life come from, but it answers the question of how it changes.

Please don't confuse the issue of the start of life with how it changes. Evolution as it has been corrected and adapted to incorporate DNA, RNA, etc., is true in the scientific sense of true, meaning testable, observable, etc. This being said, the chain of being showing all the species specific changes up to humans is not crystal clear either due to reliance on fossils. However, this does not refute biological evolution in general.

We share too many vestigial genetic and physical features with other non-mammalian species to have been created "as is." In terms of design, there are too many redundancies and unecessary features for our design to be "truly intelligent."

Please do your OWN homework before spouting dogma.

[j_mcdonald-2009]

Sorry, jank, but that's just idiotic. The argument being described is akin to trying to determine if two people from the 17th century were father and son, or were cousins. Your post amounts to saying that having such an argument is evidence that children bear no particular resemblance to their parents. Drivel.

[SeanMMcLaren]

pft, and I notice the Discover byline. eh, still nicely done, and at least CBS outsources well =p

[SeanMMcLaren]

That first paragraph should be canonical for any article of this type. And just as I was warming up for another round of "the mainstream media is terrible at reporting on science." Good on ya mate.