11/13/2003
Sleuthing Old Stuff
The October 31 issue of Science contains three detective stories involving old things, namely, old trees, a much older mummy and extremely old fliers. I was drawn to the article “Methuselahs in Our Midst” by Kevin Krajick not so much by the ages of the trees but by their locations in the Eastern U. S. For example, arborist Fred Breglia found gnarly 500-year old red cedars rooted into a cliff overlooking the Schoharie Creek in New York State. These old cedars are unimpressive specimens, only 10 inches or less in diameter. However, Schoharie Creek brought to mind the 1960s and two summers my wife and our two sons spent at Camp Schoharie in the Catskills in New York.
My wife was one of the camp nurses and she and our sons were the only gentiles in this Jewish camp. It was quite an enriching experience for all. I would drive to the camp on Fridays after work and return home Sunday with enough food to last me until the next Friday, courtesy of the nice lady in the camp kitchen. She was the first person I had met who was a survivor of the Holocaust. Thanks to her, I developed a lifelong taste for bagels with cream cheese and lox. There were many other memories such as my wife breaking her leg her very first day in camp! With a walking cast, she stayed through the summer. (After many days spent sewing laundry labels on the kids’ clothes she wasn’t about to come home!)
Krajick’s article also contains a photograph of an ancient beech tree in Cook Forest in Pennsylvania. Cook Forest reminded me of another camping experience in the 1950s. A bunch of us graduate students at the University of Pittsburgh rented a cabin in Cook Forest and this nurse, who was going for her degree in nursing education, was invited by some mutual friends to join the group. It was a most enjoyable few days and, yes, I ended up marrying that nurse. Strangely, I don’t remember any old trees.
Where does the detective work come into play? Tree rings in old trees in the Eastern U. S. can reveal something about the severity of earthquakes. For example, the colossal New Madrid, Missouri earthquakes in 1811-1812 were so severe that some old trees were shaken badly enough that they virtually stopped growing for 50 years before resuming normal growth. One of the biggest natural disasters for the U.S. in the past century was the Dust Bowl in the 1930s. Old trees reveal that at least two, even more severe drought conditions existed several hundred years ago in other regions of the country. One of these extended droughts is thought to be the reason for the disappearance of the first English colony in Virginia in the 1580s. Other studies of tree rings shed light on long term climate history and global warming trends.
Much older than these trees is the mummy, that of the famed Alpine Iceman. I’m sure you’ve all seen pictures of the Iceman, whose remarkably well-preserved body was found frozen in a glacier back in 1991. The Iceman, called Oetzi (Otzi with an umlaut over the O), was the subject of controversy inasmuch as the body was found in the mountains near the border of Austria and Italy. Both countries claimed Oetzi but it was determined that the body was found within about a hundred yards of the border on the Italian side. Today, Oetzi lies in cold storage in a museum in Bolzano, Italy.
Why the intense interest in Oetzi? He lived and died roughly 5200 years ago and was found with his clothing, tools, arrows and a knife. As the world’s oldest and best-preserved mummy, Oetzi provides a valuable window into life back in those prehistoric times. An arrow blade found in his left shoulder and wounds on his hands led to the belief that Oetzi died in a fight with his adversaries. Now an article by Sarah Ives posted on October 30, 2003 on the National Geographic Web site cites research by Australian archaeologist Thomas Loy and his colleagues. They looked at DNA samples of blood found on an arrow and the knife carried by Oetzi and on his goatskin coat.
The researchers report that the blood on the arrow belonged to two other individuals, the blood on the knife belonged to a third individual and the blood on the coat was that of a fourth person. They conclude that Oetzi was in a battle for his life with a number of attackers and speculate that he may have been carrying a wounded comrade whose blood spilled onto his clothing. Other workers believe it more likely that Oetzi’s death was part of a ritual sacrifice – always controversy.
Whatever the nature of Oetzi’s demise, others are interested in Oetzi’s background and early life. Was Oetzi an Austrian who just wandered over to Italy across the border? Of course, back in those days more than 5,000 years ago, there was no such border. The Science article “Origin and Migration of the Alpine Iceman” addresses this question. The five authors of the paper include three workers from two universities in Australia and one each from the Swiss Federal Institute in Switzerland and Colorado College in Colorado Springs. Oetzi has an international following!
I won’t attempt to detail the extensive work that went into this study but it certainly impressed me that these researchers could show it likely that the Iceman was born in and most likely did not wander farther than 35-40 miles from his birthplace in his lifetime. The work places his birthplace and range in Italy, not Austria. His current resting place in Bolzano seems appropriate.
How did these workers arrive at their findings? They sampled bits of Oetzi’s teeth, bones and intestinal contents and ran analyses of the amounts of various isotopes of oxygen, carbon, and argon and of strontium and lead of a radioactive nature or origin. They compared these results with similar measurements and other observations on soil and water samples from the varying altitudes, geologic formations etc. in the areas surrounding the location where Oetzi was found. They found significant differences in the isotope ratios in the different environments. They deduced what the conditions were when the tooth enamel was formed in Oetzi’s childhood, for example. Since the youthful isotope composition is frozen into the enamel, they could figure out where he spent his childhood.
Now let’s jump from the mouth to the ear and from 5,000 to hundreds of millions of years ago. Another Science article, “Peering Into Ancient Ears” by Erik Stokstad, deals with semicircular canals. These canals in the inner ear are three loops filled with fluid at right angles to each other. The brain relies on the motion of the fluid in the loops in detecting and controlling the motions of the head and neck muscles to keep one’s bearings. The size of the semicircular canals relative to the size of an animal gives valuable insight into the agility and balance capabilities of the animal. Such capabilities come into play, for example, when a running lion or a diving eagle must keep their eyes locked steadily on their prey.
Until recently, the field of study of the semicircular canals in old fossils was rather limited. The reason was quite simple. The standard way of studying the canals was to fill the inner ears of the fossil or dead animal with epoxy and then dissolve away the skull! Well, you can imagine that with priceless ancient fossils there would be considerable reluctance to sacrifice a skull for a bit of epoxy. With the development of the CT scan used routinely in medical circles (had one myself recently), times have changed. The CT scan and a newly developed micro CT scan technique have been used to determine semicircular canal structures without any damage to the skull.
I was especially interested in the results of CT scans on fossils of one particular creature – the pterosaur. The reptilian pterosaur ruled the skies long before birds came along. It evolved to become truly huge, with wingspans sometimes as large as 30 feet! The head was occasionally adorned with very large crests. Since the first fossils were discovered, there has been the question as to whether such large fliers could have been agile enough to swoop down on fish or other prey. The article cites CT scan work just published in Nature by Lawrence Witmer and colleagues at Ohio University College of Osteopathic Medicine. They have found that the semicircular canals in pterosaurs are even larger relative to size than in birds. Not only that but the part of the brain that receives the balance information was also found to be larger relative to size than in today’s birds.
The researchers conclude that not only were the pterosaurs agile fliers but also they could stabilize their gaze upon possible prey much like today’s eagles. While it’s sad that these monumental fliers are long gone from the scene, I for one am happy not to have to worry that one of these monsters is up there in the sky eyeing me as its evening meal!
Allen F. Bortrum
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