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12/18/2001
Contrasts
Brian Trumbore has graciously given me a couple weeks off so
this will be my last column of 2001. I''ll be back on January 8,
2002. Accordingly, let me begin by wishing you a happy holiday
and a peaceful New Year, hopefully without any events like
those of September 11. On December 11, after watching the
White House ceremonies marking the 3-month anniversary of
September 11, we embarked on a drive to New York to see my
wife''s surgeon. Looking at the New York skyline, bereft of those
striking towers, I thought how small the Empire State Building
now seems. In contrast, when we first moved to New Jersey in
1952, the Empire State was the tallest building in the world and
we would gaze upon it in wonder.
The hospital where my wife had her surgery is only a dozen or so
blocks away from the surgeon''s office. I mentioned last month
that the drive home from the hospital following my wife''s
surgery took two and a half hours. In contrast, our follow-up visit
to the surgeon''s office was remarkable in that we made the
roundtrip in precisely three hours! This remarkable achievement
may be lost upon those unfamiliar with New York City traffic at
this, or for that matter, any time of year.
I recently mentioned in passing a very large crocodile. I''ve
since watched a National Geographic TV program about that
crocodile, Sarcosuchus imperator or, as it''s affectionately known,
SuperCroc. Actually, there''s nothing affectionate about this
crocodile, whose fossil remains were found last year in Niger in
Africa. This was one fearsome animal that was capable of
grabbing and subduing a moderately good size dinosaur. And it
probably did. SuperCroc was swimming around 110 million
years ago and dinosaurs nibbling on plants along the shore were
fair game.
SuperCroc was not just a big crocodile; it was huge. At 40 feet,
it was twice as long as any crocodile hanging around today. At
over 17,000 pounds, it weighed 10 times more than modern
crocs. To get to that hefty size it also lived a good bit longer. By
counting growth rings in the plates of armor on crocodiles, it is
estimated that SuperCroc lived to around 50-60 years.
One of the goals of the scientific effort on SuperCroc was to
make a realistic full-scale model of the beast, based on the skull
and bones dug up in Niger. In order to construct a realistic
model, the researchers made measurements of skull dimensions
and lengths on today''s crop of crocodiles and alligators. The
objective was to see how skull size correlates with length.
Another objective was to measure the force or pressure of the
bites of different size crocs and gators, again to find correlation
between size and nastiness of the bite. Reading about this
measurement in a journal or in National Geographic doesn''t fully
convey the risky nature of such measurements. The intrepid
scientist must place a rod containing the appropriate sensor into
the animal''s mouth in just the right position to get a good clean
bite. This looked hairy enough in a gator farm with an expert
holding the animal. What really impressed me was measuring
some of larger animals in settings where other crocs on the prowl
for a good meal were nearby. Indeed, the camera caught one
such beast lurching at the researcher, fortunately just bloodying
his leg. I would have taken up another line of work!
The full-size model resulting from this effort reveals an
unbelievably monstrous creature that looks quite capable of
snagging and handling a good size dinosaur. I just measured the
front of our house and found it to be close to 40 feet wide, the
length of SuperCroc. After watching the program, I''ve decided to
forego looking for any lost balls in or near water when I golf in
Florida next year. Those alligators lounging on the fairways will
get my full attention!
I was beginning to adjust to the existence of such a huge reptile
when I saw an article in the Star Ledger by Andres Cala of AP.
The article concerned another reptile discovered by Richard
Thomas of the University of Puerto Rico and Blair Hedges of
Penn State University. This reptile is not extinct but is living on
the Dominican Republic''s Beata Island, part of the Jaragua
National Park. It too is a reptile of quite an impressive size.
However, in contrast to SuperCroc, it only measures 1.6
centimeters (a bit more than a half inch) in length. This may not
sound impressive, except for the fact that it is reportedly the
smallest gecko ever found. Indeed, the article states that it is the
smallest of any known species of reptile, bird or mammal. A
photo shows this little lizard curled up neatly on a dime.
Back in July 2000 I wrote a column on how geckos crawl up
walls and walk on smooth glass ceilings upside down, thanks to
tiny hair-like projections from their feet and the many even
smaller split ends that actually contact the surface. The geckos
do not use suction cups to carry out their gravity-defying feats
but rely on molecular attractive forces. If you''re interested in
more details, you can pick up the column in the archives or
search the word "gecko" in this Web site''s homepage search box.
It occurs to me that such a tiny lizard must lay awfully tiny eggs.
In contrast, down in Argentina there''s a treasure trove of much
larger reptilian eggs that have survived for some 70-80 million
years. According to an item in the January 2002 issue of
Discover magazine, six "exquisitely preserved" embryos have
been found amongst thousands of dinosaur eggs. Surprisingly,
the eggs, the size of canteloupes, aren''t much bigger than ostrich
eggs. Yet some titanosaurs grew to 100 feet in length. The
embryos are a foot long and were about to be born when flooding
buried the nesting place and preserved its contents. The most
exciting thing about the embryos was that they contained
impressions of skin. The impressions clearly show typical skin
of a reptile with its scaly features. Other features, such as the
tiny teeth, about a tenth of an inch long, were also preserved.
We''ve been dealing with contrasts in size and travel times. Our
quest for rapid transport has led to the speeding jetliners which,
with their huge loads of fuel, we''ve seen can be turned to evil
purposes. In contrast, it''s refreshing to follow up on an aircraft
that moves no faster than the speed limit in most school crossing
zones. This is NASA''s Helios, a flying wing that is over 240 feet
long (6 times as long as SuperCroc) with 14 propellers and some
62,000 solar cells. It probably weighs less than your car. On
August 13, the unmanned Helios took off from the Hawaiian
island of Kauai and, at the blinding speed of about 25 miles per
hour, climbed to 96,863 feet. It then landed back at its base after
a 17-hour flight powered only by the sun. The flight was over
10,000 feet higher than the previous altitude record for an aircraft
not powered by rocket. The previous record was held by the SR-
71 spy plane, the world''s fastest jet.
At nearly 97,000 feet, the sky is almost black and you can see
stars during the daytime. The air is about a hundred times
thinner than what we''re used to on Earth''s surface. In fact, the
atmosphere is almost as thin as it is on Mars. Obviously, the
experience gained with Helios would be useful for future flying
missions over that planet. Here on Earth, if Helios can be made
to stay up for weeks or months, it would be much cheaper than
launching a telecommunications satellite. I suspect that the
environment would also benefit from the lack of rocket
emissions into the atmosphere. The challenge now is to make
lightweight fuel cells to store the sun''s energy and run the craft at
night.
The plane is piloted by remote control from the ground. I''ve
mentioned on occasion my friend Dan in Honolulu. Dan is a
flyer of model airplanes and when I was in Hawaii earlier this
year he took me out to watch his fellow enthusiasts fly their
planes. I suspect he''d die for the opportunity to hop over to
Kauai and pilot Helios!
Allen F. Bortrum
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