A Million Years

"Never in a million years!" I've said it a million times... this off-handed reference to some highly unlikely suggestion or hypothetical outcome. Haven't you?

Implicit in our use of this expression is our cavalier perspective toward this particular interval of time. It seems a safe exaggeration, since we are confident that no living person could, with certainty, recount one single event that took place a million years ago. In fact, that realm of the past, as well as even more recent frames of time, is oft referred to as "pre-history".

But, of course, the student of Geology, Archaeology or Anthropology is required to be much more than cavalier. In recent years I have taken fresh interest in these three disciplines. My current perspective takes into account that a million years may be less than one tenth the age of this planet of ours. It also takes into account that deep pre-history played out in an environment dramatically different than the one that now supports us. It cautions me to "never say never".

As I strive to discover more information and keep abreast of new data regarding the evolution of earth and mankind, I often return to an amazing tome penned by H.G. Wells in the 1930's titled, "Outline of History". Yes, I refer to that same H.G. Wells who wrote "War of the Worlds". "Outline..." is his non-fictional gift to the armchair historian/geologist/anthropologist written in a most engaging and concise manner which makes an overwhelming body of theory and hypothesis seem, not only comprehensible, but as appealing as a novel. It is a perfect introduction for the novice and a useful review for any of the related disciplines. If your interest is piqued, Wells can be found at Ibiblio.

Cassini Mission

Published Sep. 12, 2007

By ALICIA CHANG - AP Science Writer

LOS ANGELES(AP) The international Cassini spacecraft went into safe mode this week after successfully passing over a Saturn moon that was the mysterious destination of a deep-space faring astronaut in Arthur C. Clarke's novel "2001: A Space Odyssey."

Cassini flew within 1,000 miles of Iapetus on Monday and snapped images of its rugged, two-toned surface. As it was sending data back to Earth, it was hit by a cosmic ray that caused a power switch to trip. The spacecraft was not damaged, but had to turn off its instruments and relay only limited information.

Mission controllers have since sent commands for Cassini to resume normal transmission and scientists recovered all the data from the moon flyby despite a nearly 12-hour delay. The spacecraft was expected to be fully functional by week's end.

Iapetus, Saturn's third-largest moon, gained science fiction fame in Clarke's mind-bending novel "2001: A Space Odyssey," that was developed in concert with Stanley Kubrick's 1968 movie by the same name.

Clarke surprised the Cassini team with a five-minute video played Tuesday during an internal meeting at NASA's Jet Propulsion Laboratory in Pasadena. Clarke, who lives in Sri Lanka, told scientists he looked forward to viewing photos from the flyby.

Even before Clarke's taped greeting, scientists waxed poetic about Cassini's encounter with Iapetus and the fictional Discovery spaceship's rendezvous with Japetus, as the Saturn moon is known in Clarke's book.

"From time to time, you would hear references to the novel. People would say, 'I wonder if Cassini will see the monolith,'" said Cassini program manager Robert Mitchell.

The monolith refers to a galactic slab on Japetus that swallows the hero astronaut David Bowman and transforms him into an immortal. Kubrick dropped Saturn from the script and made Jupiter's moons the destination instead to prevent confusion among moviegoers about how the spaceship can slingshot from one planet to another.

It's the second time Cassini has flown by the walnut-shaped Iapetus, but the latest images are the crispest yet. The spacecraft focused on a jagged ridge surrounded by mountains near the equator that look geologically old. Scientists hope to find out what forces caused the ridge to form and how long it has been in existence.

"Iapetus is really a time machine. We're looking back at a really old surface," said Cassini scientist Torrence Johnson of JPL.

Cassini mission: http://saturn.jpl.nasa.gov/home/index.cfm

Genealogy by Genetics

Have you heard of the Genographic Project?

http://www.msnbc.msn.com/id/10095659/

Advances in genetic research, good or bad, offer new paths of exploration for gaining insight into the history of humankind. Technology born in the rarified air of academic endeavor seems always destined to thread itself into the lives of proverbial "common man". You might find this info intriguing, or ... unnerving. Come back and share your thoughts.

Clock / Computer ???

By NICHOLAS PAPHITIS - Associated Press Writer

ATHENS, Greece(AP) Imagine tossing a top-notch laptop into the sea, leaving scientists from a foreign culture to scratch their heads over its corroded remains centuries later. A Roman shipmaster inadvertently did something just like it 2,000 years ago off southern Greece, experts said late Thursday.

They claim to have identified a handful of puzzling metal scraps found in the wreck as the earliest known mechanical computing device that pinpointed astronomical events.

Known as the Antikythera Mechanism _ from the island off which the Roman ship sank _ the assemblage of cogs and wheels looks like the innards of a very badly maintained grandfather clock.

Only the first clockwork devices appeared more than a thousand years later in western Europe.

"It was a pocket calculator of the time," said astronomer John Seiradakis.

Seiradakis, a professor of astronomy at the University of Thessaloniki, was among an international team including British, Greek and U.S. scientists who used specially developed x-ray scanning and imaging technology to analyze the corroded bronze, revealing hidden machinery and a form of written user's manual.

"We have used the latest technology available to understand this mechanism, yet the technological quality in this mechanism puts us to shame," said project leader Mike Edmunds, professor of astronomy at Cardiff University. "If the ancient Greeks made this, what else could they do?"

Ever since its discovery a century ago, the complex mechanism has baffled scientists.

Edmunds said the 82 surviving fragments, dated to between 140-100 B.C, contain over 30 gear wheels, and "are covered with astronomical, mathematical and mechanical inscriptions."

"It was a calendar of the moon and sun, it predicted the possibility of eclipses, it showed the position of the sun and moon in the zodiac, the phase of the moon, and we believe also it may have shown the position of some of the planets, possibly just Venus and Mercury," he said.

The box-shaped mechanism _ the size of office paper and operated with a hand-crank _ could predict an eclipse to a precise hour on a specific day.

"The design of the mechanism is very wonderful, making us realize how highly technological the ancient Greek civilization was. Much more so perhaps than we thought," Edmunds said.

The new study of the ancient device, with the aid of Hewlett Packard and the British x-ray equipment maker X-Tek, more than doubled the amount of the inscriptions readable on the mechanism.

"We will not yet be able to answer the question of what the mechanism was for, although now we know what the mechanism did," Edmunds said.
The first comparable devices known in the west were clockwork clocks developed during the Middle Ages.

The Antikythera device was probably made on the island of Rhodes, which had a long tradition in astronomy and applied mechanics.

The sunken ship, thought to have been carrying plunder from Roman-conquered Greece to Rome, is believed to have sailed from Rhodes.

It sank in the first century B.C.

The wreck was found in 1900 by Greek sponge-divers 50 meters (164 feet) deep and just off the small island of Antikythera, on what is still a busy trade route between southern mainland Greece and Crete.

A systematic search of the wreck revealed a group of bronze and badly weathered marble statues, as well as the Antikythera Mechanism, in what remained of its original wooden casing.

All the finds _ including wine jars, pottery, silver coins and plates _ are now at the National Archaeological Museum in Athens.

Weary Theory

September 8, 2006 ... Rochester in the News
Genetic Surprise Confirms Neglected 70-Year-Old Evolutionary Theory

...... Scientific American (September 8, 2006) ......
Wandering Fly Gene Supports New Model of Speciation

...... UPI (September 7, 2006) ......
Old, Unpopular Gene Theory Proved
CorrectMobile Genes Found to Pressure Species Formation


Biologists at the University of Rochester have discovered that an old and relatively unpopular theory about how a single species can split in two turns out to be accurate after all, and acting in nature.

The finding, reported in today's issue of Science, reveals that scientists must reassess the processes involved in the origin of species. The beginnings of speciation, suggests the paper, can be triggered by genes that change their locations in a genome.





JP Masly shows (drosophila)
flies he used
to confirm
old evolutionary theory




"In the 1930s there was speculation that parts of chromosomes that switch from one location to another might cause a species to split into two different species," says John Paul Masly, lead author of the paper and doctoral student at the University of Rochester. "Showing that it was more than an academic idea was difficult, and required a bit of luck. Other genetic causes of speciation are clearly documented in nature, and it wasn't until we had the ability to sequence whole genomes that we could even attempt to investigate the question."

Curiously, the hypothesis nearly died twice.

Theodosius Dobzhansky, a well-known evolutionary geneticist, studied fruit flies in the infant days of genetic research in 1930. He mapped out how it might be possible for sections of chromosomes to relocate themselves in a genome. Those mobile sections can cause sterility in inter-species hybrids, which can act as a speciation pressure.

In theory, the idea was sound, but scientists long debated whether it actually happened in nature. Eventually a competing theory involving the gradual accumulation of mutations was shown to occur in nature so often that geneticists largely dismissed the moving gene hypothesis.

"We knew going into this that it was a risky experiment," says Masly. "But we hoped we could pull it off."

Over the span of the six-year project, the prospects of bolstering the controversial evolutionary idea looked increasingly bleak.

Masly brought together two species of fruit fly—the workhorses of the genetics world—to see what genes were active when they were crossbred. One species, Drosophila melanogaster, had its genome already sequenced, making that part of the job much easier. The second species, Drosophila simulans, was still in the process of being sequenced, which meant much of the work had to be done by hand by Masly and his collaborators.

Masly knew that chromosome #4 on melanogaster held a gene that was somehow very important for fertility—information found earlier by Rochester biologist H. Allen Orr. Crossbreeding the flies proved tricky because a few million years of evolution separated the species, but after a few nudges the flies produced what Masly was looking for—a sterile male.

This is when Dobzhansky's 70-year-old hypothesis nearly died for good.

The reigning theory of speciation says that the genes causing hybrid sterility must have diverged slowly by normal evolutionary changes. To determine if this was true, Masly had only to look at chromosome #4 and find the gene on it that caused the hybrid sterility.

But there was no gene there.

"Something was all wrong. We couldn't find the gene and we were this close to giving up on the whole project"

"There was a great, 'Oh no,' moment," says Masly. "I'd been working on this for six years and it was starting to look like it was all for nothing. Something was all wrong. We couldn't find the gene and we were this close to giving up on the whole project."

But once again, insights from the past came into play. Masly and Orr, Masly's advisor and professor of biology at the University of Rochester, were talking one day when Orr suddenly recalled an off-hand comment from a scientist named Hermann J. Muller in a paper 60 years earlier. Muller speculated that perhaps since the sterility in the flies is so recessive—meaning it's almost completely non-functional—perhaps the gene in question has jumped clear off the chromosome.

"It had never occurred to us that the gene might have moved right off chromosome #4 in simulans," says Masly. As the simulans' genome was newly sequenced, Masly called a colleague, geneticist Corbin D. Jones, a co-author of the paper and Rochester graduate, who was studying the simulans genome.

Over the phone one day in the lab, Jones told Masly what his analysis turned up.

"You're not going to believe this, but you're right," said Jones. "It's not on the fourth chromosome. It's on the third."

"That was really exciting," says Masly. "It was completely unexpected and it made the cause of this hybrid's sterility very simple; the gene's on number four in one species and on number three in the other, so when you mate the two, every now and then you'll get a male with a combination that includes no gene at all. These guys are sterile because they completely lack a gene that's necessary for fertility."

The gene, called JYAlpha, is one of the same genes that is essential for sperm motility in the flies, as well as in humans and other mammals.

Masly's work shows a back door through which speciation can start. If the right genes jump around in the genome, a population can begin creating individuals that can't successfully mate with the general population. If other speciation pressures, like geographic isolation, are added to the mix, the pressure may be enough to split one species into two new species.

When asked if JYAlpha may be responsible for melanogaster and simulans' initial split a few million years ago, Masly replied, "That's lost to history."

Fortunately, the theory isn't.

This research was funded by the National Science Foundation, the Canadian Institutes of Health Research, and the National Institutes of Health.

Searching Ancient Clues

SAO PAULO, Brazil(AP) A grouping of granite blocks along a grassy Amazon hilltop may be the vestiges of a centuries-old astronomical observatory _ a find archaeologists say indicates early rainforest inhabitants were more sophisticated than previously believed.

The 127 blocks, some as high as 9 feet tall, are spaced at regular intervals around the hill, like a crown 100 feet in diameter.

On the shortest day of the year _ Dec. 21 _ the shadow of one of the blocks, which is set at an angle, disappears.

"It is this block's alignment with the winter solstice that leads us to believe the site was once an astronomical observatory," said Mariana Petry Cabral, an archaeologist at the Amapa State Scientific and Technical Research Institute. "We may be also looking at the remnants of a sophisticated culture."
Scientists not involved in the discovery said it could prove valuable to understanding pre-Columbian societies in the Amazon.

"No one has ever described something like this before. This is an extremely novel find _ a one of a kind type of thing," said Michael Heckenberger of the University of Florida's Department of Anthropology.

"The traditional image is that some time thousands of years ago small groups of tropical forest horticulturists arrived in the area and they never changed _ (that) what we see today is just like it was 3,000 years ago," Heckenberger said. "This is one more thing that suggests that through the past thousands of years, societies have changed quite a lot."

Time Flies