Science Over the Edge

A Roundup of Strange Science for the Month

May/June 2020

In the News:

Paleontologists Reveal 'The Most Dangerous Place In The History Of Planet Earth' - 100 million years ago, ferocious predators, including flying reptiles and crocodile-like hunters, made the Sahara the most dangerous place on Earth. This is according to an international team of scientists, who have published the biggest review in almost 100 years of fossil vertebrates from an area of Cretaceous rock formations in south-eastern Morocco, known as the Kem Kem Group. The review, published in the journal ZooKeys, "provides a window into Africa's Age of Dinosaurs" according to lead author Dr Nizar Ibrahim, an Assistant Professor of Biology at the University of Detroit Mercy and Visiting Researcher from the University of Portsmouth. About 100 million years ago, the area was home to a vast river system, filled with many different species of aquatic and terrestrial animals. Fossils from the Kem Kem Group include three of the largest predatory dinosaurs ever known, including the sabre-toothed Carcharodontosaurus (over 8m in length with enormous jaws and long, serrated teeth up to eight inches long) and Deltadromeus (around 8m in length, a member of the raptor family with long, unusually slender hind limbs for its size), as well as several predatory flying reptiles (pterosaurs) and crocodile-like hunters. Dr Ibrahim said: "This was arguably the most dangerous place in the history of planet Earth, a place where a human time-traveller would not last very long." Many of the predators were relying on an abundant supply of fish, according to co-author Professor David Martill from the University of Portsmouth. He said: "This place was filled with absolutely enormous fish, including giant coelacanths and lungfish. The coelacanth, for example, is probably four or even five times large than today's coelacanth. There is an enormous freshwater saw shark called Onchopristis with the most fearsome of rostral teeth, they are like barbed daggers, but beautifully shiny."

Examining Heart Extractions In Ancient Mesoamerica - Sacrificial rituals featuring human heart extraction were a prevalent religious practice throughout ancient Mesoamerican societies. Intended as a means of appeasing and honoring certain deities, sacrifices served as acts of power and intimidation as well as demonstrations of devotion and gratitude. Human sacrifices were highly structured, complex rituals performed by elite members of society, and the ceremonies included a myriad of procedures imbued with symbolic significance. In the study, "Open Chests and Broken Hearts: Ritual Sequences and Meanings of Human Heart Sacrifice in Mesoamerica," published in Current Anthropology, Tiesler and Olivier conduct an anatomical analysis of skeletal evidence and compare it with systematically checked historical sources and over 200 instances of ceremonial heart extraction in codices. Focusing on the location of openings created in the chest to allow for the removal of a victim's heart and blood, the authors examine the resulting fractures and marks in articulated skeletons to infer about the nature of the entry wound and the potential instrumentation used. The breadth of source material and the multitude of disciplinary approaches has led to debate among scholars. While the archaeological record provides evidence of these ceremonies, less tangible elements of the rituals--such as the symbolism of these processes--may be harder to discern. Descriptions of human sacrifice and heart extraction can likewise be found in written witness testimonies and in Mesoamerican iconography. However, witness accounts were often inconsistent, especially concerning the position of the extraction site. Utilizing forensic data in conjunction with an analysis of ethnohistorical accounts, the authors detail three distinct heart extraction methods: cutting directly under the ribs (subdiaphragmatic thoracotomy); making an incision between two ribs (intercostal thoracotomy); or by horizontally severing the sternum in order to access the heart (transverse bilateral thoracotomy). While previous research indicates subdiaphragmatic thoracotomy was a common practice, Tiesler and Olivier expand upon the existing literature by providing reconstructions of intercostal thoracotomy and transverse bilateral thoracotomy.

Giant Teenage Shark From The Dinosaur-Era - In 1996, palaeontologists found skeletal remains of a giant shark at the northern coast of Spain, near the city Santander. Here, the coast comprises meter high limestone walls that were deposited during the Cretaceous period, around 85 million years ago, when dinosaurs still roamed the world. Scientists from the University of Vienna examined this material now and were able to assign the remains to the extinct shark family, Ptychodontidae, a group that was very specious and successful in the Cretaceous but suddenly vanished mysteriously before the infamous end-Cretaceous extinction event. Shark vertebrae bear important information about a species' life history, such as size, growth and age, which are saved as growth rings inside the vertebra, like in the stem of trees. Statistical methods and the comparison with extant species, allowed the scientists to decode these data and reconstruct the ecology of this enigmatic shark group. "Based on the model, we calculated a size of 4-7m and an age of 30 years for the examined shark. Astonishing about this data is the fact that this shark was not yet mature when it died despite its rather old age." states Patrick L. Jambura, lead author of the study. Sharks follow an asymptotic growth curve, meaning that they grow constantly until maturation and after that, the growth curve flattens resulting from a reduced growth rate. "However, this shark doesn't show any signs of flattenings or inflections in the growth profile, meaning that it was not mature, a teenager if you want. This suggests that these sharks even grew much larger (and older)!" The study suggests that ptychodontid sharks grew very slow, matured very late, but also showed high longevity and reached enormous body sizes. "This might have been a main contributor to their success, but also, eventually, demise."

Promising Signs For Perseverance Rover In Its Quest For Past Martian Life - New research indicates river delta deposits within Mars' Jezero crater - the destination of NASA' Perseverance rover on the Red Planet - formed over time scales that promoted habitability and enhanced preservation of evidence. Undulating streaks of land visible from space reveal rivers once coursed across the Martian surface - but for how long did the water flow? Enough time to record evidence of ancient life, according to a new Stanford study. Scientists have speculated that the Jezero crater on Mars - the site of the next NASA rover mission to the Red Planet - could be a good place to look for markers of life. A new analysis of satellite imagery supports that hypothesis. By modeling the length of time it took to form the layers of sediment in a delta deposited by an ancient river as it poured into the crater, researchers have concluded that if life once existed near the Martian surface, traces of it could have been captured within the delta layers. "There probably was water for a significant duration on Mars and that environment was most certainly habitable, even if it may have been arid," according to lead author Mathieu Lapôtre, an assistant professor of geological sciences at Stanford's School of Earth, Energy & Environmental Sciences (Stanford Earth). "We showed that sediments were deposited rapidly and that if there were organics, they would have been buried rapidly, which means that they would likely have been preserved and protected." Jezero crater was selected for NASA's next rover mission partly because the site contains a river delta, which on Earth are known to effectively preserve organic molecules associated with life. But without an understanding of the rates and durations of delta-building events, the analogy remained speculative. The new research, published online on April 23 in AGU Advances, offers guidance for sample recovery in order to better understand the ancient Martian climate and duration of the delta formation for NASA's Perseverance Rover to Mars, which is expected to launch in July 2020 as part of the first Mars sample return mission.

Science Quote of the Month - "To me there has never been a higher source of earthly honor or distinction than that connected with the advances of science." - Isaac Newton

What's New at the Museum:

Who is the Father of Television? - Ever hear of Vladimir K. Zworykin? How about John Logie Baird? Or maybe you know the name of Paul Nipkow? If not, how about Charles Francis Jenkins? No? Well surely you have heard of Philo T. Farnsworth! Who are these people? They all have a claim to the title of "The Father of Television." Which one, if any, is the rightful owner to that moniker, however? >Full Story

Mysterious Picture of the Month - What is this?

Ask the Curator:

People Too Heavy for the Earth? - This may be a very stupid question, but I have been curious about this for a long time. When the earth was first formed, there were no people inhabiting the earth. Now there are over 6 1/2 billion people on the earth (along with all the animals now roaming the earth). I realize living things consume the resources of earth but why has not the weight of 6 1/2 billion people affected the orbit or tilt of the earth? It is an incredible amount of weight on earth that was not there before. - Diane

There are a few reasons why this weight does not affect earth's orbit. If we take the average weight of a human being as 150lbs and multiply it by 6.5 billion, then converte it to kilograms by dividing by 2.2, we get an approximate mass for all the human life on our planet as 443.19 billion kilograms (this is probably an over-estimate as the much of the world's population are children which would lower the average weight). This seems like a large number until you compare it with the mass of the earth, however, which is 6,000,000,000,000,000 billion kilograms. We are only a tiny, tiny fraction of the planet's total mass.

Accurate estimates of the planet's total biomass (all plants and animals) are hard to come by, but one often cited figure is 69,181 billion kilograms. Still only a tiny fraction of earth's total mass.

Even if people did represent a large percentage of the earth's weight our growth in numbers on the planet would not represent a change in the planets total mass. Why? Because all that we are was once part of the earth. For example 80% percent of our bodies are water. The water was here before people were on the earth; it was just located in the lakes, rivers and oceans of our planet. As a human body grows it takes on this water that was already on the planet. The water is shifted from sitting on the surface of the earth to inside your body, but the mass does not change. This is the same for all the other materials in your body and for all life.

The only way to significantly increase the weight of our planet would be for it to be hit by a large object (by large I mean planet-sized). If such a collision occurred, however, the impact would probably wipe out all life on the planet and any modifications to the orbit would be a moot point as far as human beings were concerned.

 

 

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First American Spaceflight - On May 5th of 1961, America launched it's first astronaut in space: Alan Bartlett Shepherd, Jr. He made a 15 minute sub-orbital flight reaching an altitude of 115 miles. The 2,000-lb. Freedom 7 capsule he piloted was launched from Cape Canaveral, Florida, riding the top of a Mercury-Redstone 3 rocket. During the flight, while he travelled a distance of 302 miles at ground speed of 4,500 mph, he experienced five minutes of weightlessness. While Shepard got the title of the "first American in space," he was second human in the world to leave the planet as Yuri Gagarin, a Russian cosmonaut, had taken a rocket ride into orbit a few weeks before on April 12th.

In the Sky:

Another Meteor Shower! - If you missing the Lyrid Meteor Shower last month, you have a change again this month with the n-Lyrid shower, also associated with the Lyrid constellation. May 8th will be the peak of the n-Lyrid meteor shower, though you will be able to see shooting stars in the sky staring around May 3rd and running through the 14th. The radiant point (the place the meteors seem to be coming from in the sky - is in the constellation Lyra) so look for them whenever Lyra is above the horizon. It is likely that the best viewing will occur just before dawn. The object responsible for creating the Lyrid shower has been identified as comet C/1983 H1, otherwise known as Araki-Alcock.

Observed:

CREDIT NASA, ESA, and STScI

Hubble Celebrates Its 30th Anniversary With A Tapestry Of Blazing Starbirth - On 24 April 1990 the Hubble Space Telescope was launched aboard the space shuttle Discovery, along with a five-astronaut crew. Deployed into low-Earth orbit a day later, the telescope has since opened a new eye onto the cosmos that has been transformative for our civilization. Each year, the NASA/ESA Hubble Space Telescope dedicates a small portion of its precious observing time to taking a special anniversary image, showcasing particularly beautiful and meaningful objects. These images continue to challenge scientists with exciting new surprises and to fascinate the public with ever more evocative observations. This year, Hubble is celebrating this new milestone with a portrait of two colourful nebulae that reveals how energetic, massive stars sculpt their homes of gas and dust. Although NGC 2014 and NGC 2020 appear to be separate in this visible-light image, they are actually part of one giant star formation complex. The star-forming regions seen here are dominated by the glow of stars at least 10 times more massive than our Sun. These stars have short lives of only a few million years, compared to the 10-billion-year lifetime of our Sun. The sparkling centerpiece of NGC 2014 is a grouping of bright, hefty stars near the centre of the image that has blown away its cocoon of hydrogen gas (coloured red) and dust in which it was born. A torrent of ultraviolet radiation from the star cluster is illuminating the landscape around it. These massive stars also unleash fierce winds that are eroding the gas cloud above and to the right of them. The gas in these areas is less dense, making it easier for the stellar winds to blast through them, creating bubble-like structures reminiscent of brain coral, that have earned the nebula the nickname the "Brain Coral."

LGM:

Zeep and Meep are on a well deserved vacation. In their place we feature highlights from their past adventures.

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