Fossil raises puzzling questions about how upright body plan of great apes evolved

Fossil raises puzzling questions about how upright body plan of great apes evolved
The fossilized hipbone of an ape called Sivapithecus is raising a host of new questions about whether the upright body plan of apes may have evolved multiple times. "What we do know is that the evolution of the orthograde body plan in apes is not a simple story,” noted Harvard's Michèle Morgan, co-author of the paper.

For decades, scientists have recognized the upright posture exhibited by chimpanzees, gorillas, and humans as a key feature separating the "great apes" from other primates, but a host of questions about the evolution of that posture—particularly how and when it emerged—have long gone unanswered.

For more than a century, the belief was that the posture, known as the orthograde body plan, evolved only once, as part of a suite of features, including broad torsos and mobile forelimbs, in an early ancestor of modern apes.

But a fossilized hipbone of an ape called Sivapithecus is challenging that belief.

The bone, about 6 inches long, is described in a paper in the Proceedings of the National Academy of Sciences (PNAS) co-authored by Michèle Morgan, museum curator of osteology and paleoanthropology at Harvard's Peabody Museum of Archaeology and Ethnology, and colleagues including Kristi Lewton, Erik Otárola-Castillo, John Barry, Jay Kelley, Lawrence Flynn, and David Pilbeam. The finding has raised a host of new questions about whether that upright body plan may have evolved multiple times.

"We always thought if we found this body part, that it would show some of the features we find in the living great apes," Morgan said. "To find something like this was surprising."

Where modern apes have large, broad chests, Sivapithecus is believed to have had a relatively narrow, monkey-like torso, but facial features that closely resemble modern orangutans. That mixture, showing some ape- and monkey-like features, has left researchers scratching their heads about the arrangement of the primate tree, and raises questions about how the stereotypically ape-like body plan evolved.

"Today, all the living great apes—gorillas, orangutans, chimps—have very broad torsos … and people had commonly thought that this torso shape was shared among all the great apes, meaning it must have evolved in a common ancestor," Morgan said.

"We initially believed that Sivapithecus, with a narrow torso, was on the orangutan line, but if that is the case, then the body shape would have had to evolve at least twice," she added. "There are a lot of questions that this fossil raises, and we don't have good answers for them yet. What we do know is that the evolution of the orthograde body plan in apes is not a simple story."

What Sivapithecus may ultimately demonstrate, said Flynn, assistant director of the American School of Prehistoric Research at the Peabody Museum, is that evolution doesn't occur in a straight line, but happens as a mosaic across many species.

"What this speaks to is a rich tree with a lot of branches," Flynn said. "There are not just one or two branches that reach back into the Miocene (epoch). It's a very rich and complex tree.

"I think we sometimes take the easy route of trying to understand these fossils based on creatures we find today," Flynn said. "But what we're finding out time and again is these 10- or 12- or 15-million-year-old creatures were their own entities. Today is not always a very good model for the past."

To fully understand where Sivapithecus belongs in the evolutionary tree of apes, Flynn said, more fossils must be found, and additional research must be conducted.

"It's a very easy thing for people to ask, why do we need to go find more fossils; don't we already know everything? The answer is no," he said. "We're only just beginning to understand what we don't know. And as we learn more, there are more interesting and exciting questions we can ask, and hopefully we can answer."


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Feb 04, 2015
How did the upright posture evolve? Gee, that's hard to figure out. Monkeys have hands for feet so they can climb trees. I wonder what evolution would do to a species that was suddenly prevented from climbing and forced to stand up and walk around to forage instead? hmmmm, I got nothin

JVK
Feb 04, 2015
"...evolution doesn't occur in a straight line, but happens as a mosaic across many species."

That's why it is called ecological adaptation. The mosaics are nutrient-dependent and the pheromone-controlled physiology of their reproduction links species from microbes to man via the biophysically constrained chemistry of protein folding.

See: Rapid Evolution Changes Species in Real Time http://discoverma...ast-lane

Excerpt: "We are no longer forced to infer evolution from its historical footprints in the fossil record or from dusty collections of moths," Reznick says.

Quit pretending that you don't know that he is claiming there is no such thing as evolution across millions of years -- or billions, for that matter.

See: http://www.scienc...4131.htm The greatest absence of evolution ever reported... a type of deep-sea microorganism that appears not to have evolved over more than 2 billion years."

Feb 04, 2015
@jamie

We all know you are delusional creationist.

You don't need to keep advertising and spamming.

JVK
Feb 05, 2015
What you know and everyone else knows is that you cannot defend any aspect of a ridiculous theory that claims mutations lead to evolution.

You are a delusional theorist at a time when all aspects of biologically-based cause and effect have been placed into the context of nutrient-dependent amino acid substitutions that differentiate the cell types of all individuals of all genera.

The obvious problem that the unchanged bacteria presents to the biologically uninformed is that it represents nutrient-dependent pheromone-controlled epistasis, which is inconceivable across 2 billion years of changing ecosystems. The same problem arises at the other end of the time frame with rapid evolution.

No matter how you approach the topic, the theories contradict themselves and make examples of those who have touted them. They exemplify biologically uniformed science idiots, who refuse to learn anything about cause and effect.

Feb 05, 2015
@ JVK-Skippy. How you are today podna? Yeah, I'm still fine and dandy, thanks.

Have you had any luck finding something that explains how the hydrogen atoms at the beginning of the universe can smell the other hydrogen atoms energies like you said they did?

I can not find anything about hydrogen atoms having a nose to smell with. Also I can not find anything about hydrogen atom energies having any smells even if they did have the noses.

Feb 05, 2015
The biologically uninformed continue to yell: MUTATIONS! (JVK, DEC 18, 2014)


I'll let your own words do the talking, JVK, since you have YET AGAIN introduced that term to a thread.

ROTFLMAO!

JVK
Feb 05, 2015
What you know and everyone else knows is that you cannot defend any aspect of a ridiculous theory that claims mutations lead to evolution.


It is useless for biologically uninformed science idiots to continue to challenge my patience. Until they present experimental evidence of biologically-based cause and effect that support a different model of the biophysically constrained chemistry of protein folding and cell type differentiation in species from microbes to man, all they are doing is attesting to their overwhelming ignorance.


Feb 05, 2015
It is useless for biologically uninformed science idiots to continue to challenge my patience.


Well considering you do not have the patience to start with that might be right. But you have to admit Cher, they do the pretty good job of challenging the gobbledygook you are so fond of.

Until they present experimental evidence of biologically-based cause and effect that support a different model of the biophysically constrained chemistry of protein folding and cell type differentiation in species from microbes to man, all they are doing is attesting to their overwhelming ignorance.


Does that mean you are not going to tell how the hydrogen atoms can smell the energies in other hydrogen atoms at the beginning of the universe like you said they did?

JVK
Feb 05, 2015
https://books.goo...b5IDkSQC
At Home in the Universe: The Search for Laws of Self-organization and Complexity
Stuart A. Kauffman
1995

The Scent of Eros: Mysteries of Odor in Human Sexuality
http://www.amazon...9523383X
1995/2002

https://books.goo...lZ8vnVYC
Reinventing the Sacred: A New View of Science, Reason, and Religion
Stuart A. Kauffman
2010

https://books.goo...cdmhjIYC
Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature is Almost Certainly False
Thomas Nagel

Two of the books above predicted the findings in Nutrient-dependent/pheromone-controlled adaptive evolution: a model. http://www.ncbi.n...24693353

Those findings link light-induced amino acid substitutions to cell type differentiation in all cells of all individuals of all species from microbes to man.

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