September 2020 – Stone Fig

Petroglyph Trail

It was 1993. We went out west to see the land and the National Parks. We traveled in the arc of the states of the Four Corners; New Mexico, Colorado, Utah, Arizona.

Our first stop was Mesa Verde National Park in southwest Colorado. We wanted to see the magnificent remains of the cliff houses built by Native Americans centuries before.

But 700 years after they built the cliff house, they left them. The community was not destroyed by fire or earthquake, but something happened, and the People left. Other People known as the Pueblo Indians came hundreds of years after the original inhabitants had left. The Pueblo Indians called the builders of the cliff houses the Ancient Ones, the Anasazi.

The Anasazi had lived on these mesas for nearly a thousand years, from approximately 600 C.E. (Common Era, after the birth of Christ) to 1300 C.E.). Then, suddenly, they had left their homes, their places of ceremony, their work, their pottery, and they had gone. It is surmised that perhaps the cause was a change in the climate that made the crops fail. Several theories have arisen, but it is generally felt that their descendants are the modern day Pueblo Indians.

When we visited the ruins of the cliff houses, we had a fascinating experience. We were able to tour some of the ancient homes and see their construction. We climbed ladders. We entered rebuilt pit houses. We hiked trails. But it always seemed that we were with a rather sizable group. And we did not see much in the way of wildlife. I would see some Mule Deer when I would go out in the early morning for a walk at sunrise. But other than that and the occasional bird heard up in the trees, it seemed as if we humans were alone on Mesa Verde.

My son, a young outdoorsman, felt the same way. He and I wanted to get on a trail that was not so heavily traveled so we might see what we might see. His interest lay in snakes. Mine did not.

We stopped at the Visitors’ Center and asked the Ranger where we might go for a hike where it was not so crowded. We thought perhaps in the forests along the rim of the mesa. We were told that at that time of day the Petroglyph Trail was usually not crowded.

We made sure we had water with us. And as always, I carried a trail map so we would know where we were. And we set off.

We quickly moved from the trail head into the pine forest that then covered much of the park. It was a well-marked trail. There were some tight spaces and steep climbs up hewn stone steps, but it was very enjoyable. The trail was about 700 feet above the canyon floor.

The trail wandered along the side of the mesa about 100 feet below its top. From our map I could tell that we had covered a good part of the trail and were approaching an area that looked out over the lower portions of the park. Near the end of the mesa, the canyon widened to meet another canyon. We would have a good view out across the canyons.

The trail had been rocky, and as we neared this point I was focused on the trail in front of me. If it hadn’t been for the sign, we might have walked right past the petroglyph panel. The sign said, “Do Not Touch”.

Touch what I thought? But it caused me to stop and look up. The petroglyphs we were looking for were high above the sign, well above the level of my head. The Petroglyphs were inscribed in the sheet of stone that formed the side of the mesa. The Petroglyphs were in good condition.

The height of the inscribed figures above the trail has doubtlessly protected the panel from damage as they are out of the reach of curious hands. The Petroglyphs were plain to see and included animals, hand prints, human shapes, and geometric designs. However, their meaning, implied by the ancient carvers, is lost in time. One circle did catch my eye as the possible cycle of the moon with the new moon hidden from view behind a mesa jutting high into the night sky.

As we walked back, we talked of the possible meaning of the glyphs and why and when they might have been carved. We talked of how some of the mysterious glyphs may have been carved by an ancient man who walked out to the point of the mesa with his son to read the messages left from before his time. Perhaps they carved a message of their own.

Our return trail crossed the top of the mesa. Before we reached the trailhead, we saw a whip-tail lizard dart across the surface of the rocks. Perhaps he was looking a bug for his dinner. He was in a hurry, so he did not become dinner for a watchful hawk.

And on this hike, no snakes.

Information on Mesa Verde National Park including trail maps can be found at https://www.nps.gov/meve/index.htm .

UPDate – Sails from Sweden

This article is an update on modern wind-propelled ocean-going ships. This was previously discussed in the article, Cylindrical Sails, posted October 1, 2018.

Naval architects and marine engineers are continually working to make ocean transport of cargo more environmentally sustainable. The vast majority of the world’s cargo whether it is manufactured goods (farm machinery or transistors/semiconductors), raw material (food stuff or metal ore), or consumer products (small appliances or clothes) are transported from point of origin to buyer by ships.

The map above is a screen shot on a summer day in the Northern Hemisphere. The number of ships traveling between ports can be seen crowding the favored shipping lanes. Other areas of the ocean are nearly empty in comparison. These shipping lanes are crowded because they are the most direct routes between ports of call. The most famous route being the Great Circle Route.

I remember as a boy seeing the ship I was traveling on being marked on its daily passage with a magnetic ship on a wall size map of the oceans. When I asked why the ship was moving up towards the North rather than going straight across the ocean, I was told that we were on the shortest route, the Great Circle Route.

This route is the shortest distance across the globe of the Earth. By taking the shortest route the ship takes less time in its crossing, thereby saving expenses and fuel costs.

The graceful arc of a Pacific Great Circle Route is shown as a black arc between Asia and North America (California). The congestion of this route can be easily seen. These routes can be made between any two ports on an ocean. Although they become more flattened near the equator and form an upside-down arc in the Southern Hemisphere.

In the last half of the 20^th century people began to realize the damage to the atmosphere due to the amount of fossil fuel being burned. This included ocean shipping which at the time burned “bunker oil,” a fossil fuel whose use and emission added tons of pollution to the atmosphere and to the sea each year.

Modern vessels use diesel generators and more efficient power plants to generate electricity that is use to drive the propellers that push these ships. The trend has been from direct drive systems for propulsion (a boiler generates steam to turn a geared shaft on which is mounted the propeller), to an indirect-drive (a diesel generator produces electricity which runs an electric motor to turn the shaft on which is mounted the propeller).

All of these systems use fossil fuels for their main power. Over the years the fuel efficiency of the ships and their engines has greatly improved. This was brought about through improved design of the vessels and their power plants. The results have been reduced operating costs as well as reductions in environmental contamination. At the same time the number of ships transporting cargo has greatly increased. The cargo tonnage offloaded in the Port of Los Angeles, California has significantly increased in the recent years. From 2000 to 2019 the general cargo off-loaded in the Port of Los Angeles more than doubled. It rose from approximately 82 million metric tons to more than 190 million metric tons. All of these goods were transferred by ships burning fossil fuel.

In order to reduce the effect of fossil fuel on the world’s atmosphere and oceans, a consortium being led by Wallenius Marine and including the KTH Royal Institute of Technology in Stockholm, Sweden and SSPA, a marine consultancy, have designed and tested models of the hull design for a modern sailing ship. These tests have been on the open water and in a testing basin.

The modern sailing vessel they are designing is a wind Propelled Car Carrier (wPCC). Wallenius Marine is leading the design of the wPCC. This type of vessel is used to transport manufactured cars and trucks. It is often referred to as a roll-on roll-off (RORO) vessel.

While the sail mentioned in the previous article was a spinning cylinder, the wPCC sails resemble the rigid sails of modern racing yachts. They are expected the propel the Car Carrier across the oceans and achieve a reduction in emissions is 90%. However it is noted that the vessel is slower than a standard RORO.

The sails have yet to come to a final design. These rigid sails will rise up from within the ship. They can also be lowered when the ship is under the control of tugs while in port.

And although I might think that I cannot wait another moment for my new Volvo to arrive, knowing that its transportation had a significantly reduced carbon foot-print is worth the small delay before I have the keys in my hand.

The initial article I read on this was from TNW (The Next Web) and can be found at https://thenextweb.com/shift/2020/09/10/swedes-boat-powered-by-wind-sailboat-ship-cargo-transatlantic/ .

A fact sheet on the wPCC may be found at https://www.sspa.se/sites/www.sspa.se/files/field_page_files/wpcc_fact_sheet_may_2020_v_1.0.pdf .

The map at the top is a screen shot of a maritime information map found at https://www.marinetraffic.com/en/ais/home/centerx:-12.0/centery:24.8/zoom:2 . It is noted that there is an agreement associated with the use of material on this web site.

Tonnage statistics for the Port of Los Angeles may be found at https://www.portoflosangeles.org/business/statistics/tonnage-statistics .

Titan Dino Egg

When I first read the news article on the Titanosaur/Sauropod egg and the embryo inside, I was completely fascinated. When I read further about the findings from the study of the egg, I was amazed both at the methods of investigation and in what the authors of the study presented about the embryo.

The egg is believed to have been a Titanosaur, several types of Sauropod which that lived in the area where the egg was discovered in what is now Argentina. A cast/fossil of one of these Sauropods, Maximo the Titanosaur, is now on display in the Field Museum in Chicago. It has taken the place on the main floor of where Sue, the largest and most complete Tyrannosaurus Rex (T-Rex) skeleton ever found use to stand. Sue is now in the second-floor dinosaur exhibit of the Field Museum.

A comparison of the completeness of the two fossils, Maximo and Sue, is interesting. The bones comprising Sue’s fossil (it is named for the discoverer of the fossil; the sex of the dinosaur is unknown) compromise approximately 90% of the mass of a complete T-Rex skeleton. By contrast, the skeleton of Maximo the Titanosaur is made from casts of fossilized bone found at several sites, and of some sculpted bones where no reference bone is available. There were about 130 fossilized bones found, not just from one Titanosaur but from six different individuals.

The initial scientific article in Current Biology on the egg and its investigation, examines several interesting aspects of the dinosaur’s life. The embryo was approximately 80% of its in ovo, inside the egg, development before it was ready to hatch out. The examination of the embryonic fossil indicates that the tiny dinosaur had what is commonly known as an “egg-tooth.” An egg-tooth is used by a young bird as it hatches to break open the shell of the egg in which it is enclosed and protected. The egg tooth later falls off once the young bird is out of its eggshell.

Another finding of the study can be understood by picturing a rabbit. A rabbit’s skull is quite narrow, and its eyes are situated well back on the sides of its skull. The rabbit is preyed on by many other animals including mammals, large birds, and snakes. The position of the rabbit’s eyes gives it the ability to have a field of vision well beyond the field of vision of a human. While our human peripheral vision from the side of our eyes allows us to see approximately to the line of our shoulder, the placement of a rabbit’s eyes allow it a field of vision well past its shoulder. The rabbit’s field of vision reaches beyond 45 degrees past its shoulders on each side. This allows them to see a predator sneaking up on them from the sides and from their rear. This is similar to what is known about the placement of eyes sockets on adult Sauropod skeletons. They also had predators that they had to watch out for.

In the study it was found that the embryo’s eye placement was more forward giving it more of a three-dimensional vision to the front. It’s not that these tiny creatures did not have predators. I imagine the predation of the new hatchlings was very high. But when they first emerged from their egg, their eyes were forward looking. Perhaps this helped them to be better able to learn to stand and walk in a straight line and to see food such as a blade of grass or a seedling tree right in front of them. But as time went on and as their body and their skull expanded, their eyes moved to the side of their skull which created a field of vision more like that of a rabbit.

The growth of the Titanosaurs was amazing. In the art at the beginning of this article, I have tried to capture a size comparison of the adult Titanosaurs to a modern human and to the fossilized egg shown as the round ball next to the human figure.

In this study the fossilized egg was approximately 10 inches in diameter. I postulate that an embryo was likely about twelve inches long when it emerged from its egg. When compared, a modern ostrich egg is more egg-shaped, the dinosaur egg being studied was more spherical. A modern Ostrich egg is approximately 10 inches long and 5 to 7 inches in diameter. The hatchling Ostrich is generally the size of a chicken. It will grow to be upwards of 8 feet tall.

The hatchling Titanosaur by contrast is assumed to be 10 to 12 inches tall at the shoulder. It would have grown to be 20 times that high at the shoulder. It will also grow to be over 120 feet long and weigh 140,000 pounds (70 tons).

The last bit of the story also speaks to the truth of modern science. At one time fossils were stolen in the field from one team of paleontologists by another team representing a different museum or university. Fossils were sometimes destroyed in the field to keep rival museums from retrieving them. Today museums and landowners and discoverers often work together to improve our knowledge of these ancient beasts and the world they lived in. There may be court cases to determine ownership or partial rights of ownership to a fossil. This allows the courts to decide the question of ownership and the fossil can be recovered and displayed and studied and enjoyed. In the case of the fossilized egg and its embryo, the fossil had been removed from Argentina illegally. When this became known to the research team, the fossil was returned to Argentina. The fossil is now housed at the museum, Museo Municipal “Carmen Funes,” in Plaza Huincul, Neuquén Province, Argentina.

Fascinating.

The picture of the herd of titanosaur sauropod Argentinosaurus is by artist Miguel Angel Amorin Fernandez. It is copied from a page in “palenontologyworld_com”, it may be found at https://www.instagram.com/p/B00DxYblpOd/?igshid=dbe23rmt94sf .

The picture of the embryo of the Titanosaur sauropod inside its egg is copied from the article, “Specialized Craniofacial Anatomy of a Titanosaurian Embryo from Argentina”, Martin Kundrat et al, published August 27, 2020 in the journal Current Biology.

The pictured size comparison of the human (at 5 feet 6inches) and the sauropod Argentinosaurus (shoulder height 20 feet) is based on the scale presented in the article “Titanosaur” that may be found at https://www.britannica.com/animal/titanosaur.

The initial news article I read on this fascinating subject was an online article in CNN. It may be found at https://www.cnn.com/2020/08/27/world/sauropod-dinosaur-embryonic-skull-scn-trnd/index.html . The pictured comparison of the size of a titanosaur egg (approximately 8 inches in diameter) is based on the comparison to an Ostrich egg in that article.

The article about Sue the T-Rex may be found on the website of the Field Museum of Chicago at https://www.fieldmuseum.org/blog/sue-t-rex .

The difference between the complete skeleton of Sue, and the mostly Cast skeleton of Maximo the Titanosaur is discussed in an article on the website of the Field Museum of Chicago may be found at https://www.fieldmuseum.org/blog/which-dinosaur-bones-are-real .

The website for the museum Museo Municipal “Carmen Funes,” Plaza Huincul, Neuquén Province, Argentina may be found at https://www.interpatagonia.com/cutralco-huincul/carmen-funes-municipal-museum.html .