There’s been a lot of talk recently about the possibility, within the next few decades, of humans not only visiting the planet Mars but actually staying there. However the mechanics of spaceflight are such that the costs of a round trip to Mars could be considerably more than twice the cost of a one-way trip. With that in mind the concept of people taking a one-way trip to Mars with the intent of establishing a self-sufficient settlement is being seriously considered.
There are many in the spaceflight community who are convinced that this is the best path to follow for colonizing Mars. Elon Musk and Space X in particular have made this concept a central part of their future plans. It’s also the idea behind the novel ‘One way’ by author S. J. Morden but with a twist.
The twist is that the people who are going to be spending the rest of their lives on Mars are convicts, prison inmates who also happen to possess some kind of technical skill. In the novel Xenosystems Operations Corp. (XO) not only runs prisons for the State of California they also have a contract with NASA to design, fabricate and assemble on location the first Mars base so why not combine their expertise and use cheap convict labour on the Red Planet?
Cheap is the operative term here. Every chapter of ‘One Way’ begins with a memo, email or transcript from a meeting at XO where ways to reduce cost are given or at least hinted at. The convicts are given only enough training to perform their own tasks, only the bare minimum of supplies are provided and even their personal effects are left behind simply because it would cost so much to send them to Mars! Not surprisingly, once on Mars it isn’t long before murder and mayhem are rampant.
The problem for ‘One Way’ is that it’s all so predictable, even from the brief outline I’ve given above you can probably guess who the bad guys really are. Seriously, I pretty much had the ending figured out before the seven convicts and one guard / handler had even left Earth. Since the story is at heart a murder mystery knowing what’s coming and whodunit is not a good thing.
Which is a bit of a shame because the story is crisply told and filled with the kind of technical details that gives you a real feeling of being there. In fact Dr. S. J. Morden is a bona fide space scientist with a degree in planetary geophysics so he easily gets high marks for accuracy. In fact ‘One Way’ almost seems as if Dr. Morden just took a rather trite crime plot and thought he could make it fresh by putting it in outer space.
Which leaves me in something of a dilemma. ‘One Way’ is a well written book, the pace is good, there are no long dry spots and again, the details are meticulously drawn. However the clumsy plot means that it simply isn’t exciting, you’re left with just trying to guess who’s the next victim even though you know who will be left standing for the final battle. So in the end I suppose I’d only recommend ‘One Way’ to those of you out there who are the true lovers of hard science fiction.
We’re all familiar with the group behavior of animals. Whether it be a big herd of Bison, a large flock of birds or a huge school of fish we’ve all wondered how so many individuals without the ability to talk to one another can coordinate their movements so precisely that the group can sometimes seem like a single living thing.
Scientists have been studying this phenomenon for a very long time, even the ancient Greeks thought about the problem. We’ve succeeded in learning a great deal in the past few decades but some of the mystery still remains.
There are several reasons why a large group of animals, almost always of the same species and often of the same size and age, would come together to form a herd, flock or school, henceforth I’m just going to call it a group if you don’t mind. Increased success in both foraging and finding a mate are two reasons but predator avoidance is probably the chief reason.
You see first of all being in a large group means that there are just more eyes keeping watch for predators so there’s much less chance of bring surprised by one. Then, when a predator does attack having a score or more prey scatter in every direction overloads the predator’s senses, confusing it so that it is more likely to miss completely.
So once a large number of animals decide to become a group how do they actually do it. Well back in 1986 a biologist named Craig Reynolds was able to model much of group behavior by assuming the animals in the group obey three simple rules.
Move in the same direction as your neighbor.
Remain close to your neighbors.
To avoid collisions don’t get too close to your neighbors.
Just what close and too close mean depends on the species and remember these rules have been imprinted onto the individuals by evolution. In other words they’re not thinking about it they just feel happier with some company but also a little room as well.
O’k, so now everybody’s moving in a group, so who now decides in which direction the group is going to go? Well since many of the species that form large groups are migratory on a large scale everybody instinctively knows the general direction to go! It’s spring so everybody knows that they’re supposed to go north, or the leaves are falling so aren’t we all supposed to fly south.
Of course that doesn’t help when it’s dinnertime and hopefully somebody knows where to find some food around here. In that case the more experienced members of the group seem to take charge and lead the way to food sources that the group used on the last migration, some such resources have been used for thousands of migrations. There is also a controversial idea that it is the hungrier members of the group who take charge after a long days travel.
Once a few members of the group start to head in a certain direction the others employ a simple quorum rule to ‘follow the leader’ until everybody is heading the same way. Usually this decision making process results in the correct choice for the group but occasionally it can cascade into exactly the wrong choice, we’ve all heard of beached whales and lemmings after all.
These decision making processes are called collective intelligence and in many ways it is the speed with which the group coordinates its actions that seems almost magical. Such speed obviously requires each individual to have fairly accurate idea of where at least its nearest neighbors are.
Vision of course is an important means of knowing where everybody else is. Now however a team of researchers at New York University’s Courant Institute of Mathematical Science has published a paper detailing that for fish and birds the ability to sense the wake left behind by the leaders also plays an vital role. “Air or water flows naturally generated during flight or swimming can prevent collisions and separations, allowing even individuals with different flapping motions to travel together.” According to Joel Newbolt, lead author of the study.
The study used a robotic ‘school’ of two hydrofoils that flap up and down and swim forward, see image below.
What they found was that the trailing flap could most efficiently swim along if it ‘surfed’ in the wake of the lead flap, maintaining just the right distance between them. This is similar to the way geese fly in a Vee formation so that trailing birds get a boost from the air currents produced by the birds ahead of them only now the wake is being used to keep the right distance between individuals.
We still have a lot to learn when it comes to the phenomenon of collective intelligence in herding animals but we are making progress in our understanding of how some species have evolved to act together for the good of everybody. If only we humans could learn that lesson!
We all learned back in high school biology how some animals, the lower animals we were usually told, were capable of regenerating a significant portion of their body if they should happen to lose it. A Starfish who had lost one of its arms and regrew it was often used as an example of this power of regeneration. All living creatures possess some ability to regenerate tissue to some degree, after all, if you trip and skin your knee on the sidewalk doesn’t your skin heal itself in time.
Other species of invertebrates are also known for seemingly amazing powers of regeneration. Animals like the hydra and flatworms can literally be cut in half and regenerate into two complete individuals. Among the arthropods those species that can regenerate most easily are those that continually molt like the crustaceans. I know this for a fact because I once had a crawfish in my fish tank who got into an argument with a catfish and completely lost one of its claws. It took two molts but eventually the crawfish was completely healed!
Regeneration among the vertebrates is more limited but there are many species of lizard that can lose their tail, usually to an attacking predator, and regrow a brand new one. The group of vertebrates that possess the greatest power of regeneration however are the amphibian salamanders and newts. One species in particular that have long been studied are the axolotl, a threatened species whose only habitat is a lake near Mexico City. The axolotl in fact can completely regenerate not only their tails but entire limbs, their jaw, the retina of their eyes and even a portion of their heart!
Axolotls are fascinating creatures not only because of their regenerative abilities but also because unlike other amphibians they never completely metamorphose into an air breathing creature but retain their water breathing gills throughout their lives. This retention of juvenal characteristics into maturity is technically known as neoteny and scientists would very much like to know is whether the two curious characteristics of neoteny and regeneration could actually be related.
In an effort to learn the axolotl’s secrets Doctor Randal Voss at the University of Kentucky has succeeded in mapping the animal’s entire DNA genome. Now many species of animals have had their DNA sequenced over the last few years but the axolotl is once again remarkable in possessing 32 billion base pairs split into 14 chromosomes. That’s fully ten times as many DNA pairs as is in the human genome and getting all of those genes in the correct order is a very complicated task.
Even though Dr. Voss and his co-author Jeramiah Smith are still assembling the axolotl’s genome they hope to soon begin the work of identifying which specific genes are responsible for the animal’s remarkable tissue regeneration abilities. While the day when human beings can regenerate body parts lost in accidents or due to disease may be years away thanks to the complete sequencing of the axolotl’s genome we can now actually see the road ahead.
Quick Post Script: Free Science Fiction!!!
I just came across a very interesting website that is offering a free collection of science fiction stories, all in electronic format ready for download. The collection is called “Everything Change Volume II” and is being offered by Arizona State University. The collection comes with a forward by noted SF writer Kim Stanley Robinson, whose novel 2312 I reviewed in my post of 26 September 2018. Click on the link below to be taken to the website.
All of the stories in the collection follow the theme of the effect of climate change on future societies, a theme that is central to many of Kim Stanley Robinson’s own works. The stories themselves are written by new authors but the chance to acquire some free science fiction is certainly something worth looking into!
The idea of telepathy, of one human mind being able to read the thoughts of another directly without requiring speech or hand signals or body language or other forms of communication has long been a part of mythology and fantasy. In the modern age telepathy has become an even more integral part of Science Fiction where aliens like Mr. Spock or mutants like Professor Francis Xavier always seem to be able to read minds. Entire novels have been written whose plots center around the idea of telepathy such as Robert Silverberg’s ‘Dying Inside’.
The term telepathy was coined in 1882 by the classical scholar Frederic W. H. Myers, a founding member of the Society for Psychical Research. In the years since then there have been many serious, although often amateurishly conducted experiments to ‘prove’ the existence of telepathy. These tests usually consisted of one test subject ‘sending’ his thought transmissions to a second test subject, the ‘receiver’, the success of the experiment being judged by how accurately the receiver can pick up the thoughts of the sender.
As an example, during the 1950s and 60s a popular technique of testing for telepathy used a deck of cards known as Zener Cards. Each card in a Zener deck contained one of five symbols, see image below. The sender would select a card at random and concentrate on the symbol. The receiver would then telepathically receive the symbol and state what symbol it was. Now with five different symbols there was always a 20% chance of just guessing the right answer so you need to score significantly higher than 20% to indicate evidence of telepathy.
Problem was that there are so many ways to cheat, even unintentionally! The biggest problem is simply allowing the receiver to see the sender so that they can pick up non-verbal clues from the sender’s expression. This can even be totally unconscious if the two subjects are very well acquainted; and a lot of telepathy tests were conducted on identical twins!
At the same time however there were a number of cases of outright fraud conducted by either the test subjects or even the researcher. Because of these deceptions today the study of telepathy is regarded as a psuedo-science. The United States National Research Council is of the opinion that “despite a 130-year record of scientific research on such matters, our committee could find no scientific justification for the existence of phenomena such as extrasensory perception, mental telepathy or ‘mind over matter’ exercises”.
Still there are plenty of people who ‘believe’ in telepathy and that’s really the problem. If you firmly believe something exists you will find evidence to support that belief no matter how incredulous, even fraudulent your evidence may be.
Now however scientists may be on the verge of inventing a technology that will enable one human being to read the thoughts of another, they are working to invent telepathy if you will. Research underway at Cornell University is taking the first steps toward the development of the world’s first brain-to-brain interface that the scientists are referring to as BrainNet, that’s right BrainNet!
What BrainNet does is use the technology of electroencephalography to record both brain signals, often called brain waves along with transcranial magnetic stimulation (TMS), see image below. These signals are then transmitted via the normal Internet and inserted into another brain by magnetic stimulation of the occipital cortex.
The first successful tests consisted of having the ‘sender’ play a Tetris like game and the decision about how to rotate the blocks is the thought to be transmitted to the ‘receiver’. In tests of five groups of players the receiver’s ability to perform the task shows an average success rate of 81.3%.
Similar experiments are being carried out at University of Washington where neuroimaging and neurostimulation technologies are being employed to transmit neural content from one subject to another in a corroborative game of 20 questions. Both of these two projects soon hope to be able to construct a ‘social network’ of human brains capable of solving problems in a cooperative fashion.
And just to show what a fast moving field of research this is while I was composing this post I came across a third team of scientists who are working to measure, decipher and convert into ordinary sound the electrical signals in our brain. Doctor Nima Mesgarani of Columbia University’s Department of Electrical Engineering has teamed up with Doctor Ashesh D. Mehta of Hofstra University’s school of medicine to created a technique for actually capturing a person’s brain waves and converting them to common English spoken by a computer.
It was Dr. Mesgarani and his team at Columbia who assembled the instrumentation that succeeded in capturing and analyzing the patterns of brain activity that occurs when a person even thinks about talking. When those patterns were fed into a voice synthesizer however the result was unintelligible.
It was at this stage that Dr. Mesgarani contacted Dr. Mehta who suggested employing the same computer algorithm that enables Amazon’s Echo and Apple’s Siri to understand human speech. Starting by recording the brain waves of volunteers saying the numbers one through ten the researchers developed a system that can ‘read’ the mind of a person thinking a number and then say it with 75% accuracy of understanding. Drs. Mesgarani and Mehta hope that before long their system will be capable of providing a means for people whose speech is impaired by paralysis or who suffer from diseases such as ALS to communicate better with the world around them.
If these experiments are successful, if it becomes possible for the neural signals, the thoughts of one person’s brain to be picked up by electronic sensors and transmitted, perhaps over great distances and then implanted into another person’s brain then scientists will have truly invented telepathy!
I’ve already discussed two very important events in space exploration that happened earlier this month. These are the New Horizons spacecraft’s flyby of the object Ultima Thule at the outer edge of our solar system along with the Chang’e 4’s successful landing on the far side of the Moon, (See posts of 2 January and 5 January 2019). Nevertheless there have also been several other news stories worthy of mention so I’ll take care of them now.
Perhaps most significant was the successful test firing of the main engines of Space X’s Falcon 9 rocket carrying their crew Dragon Capsule. This represents the first time that a man capable spacecraft has fired its engines on American soil in eight years, since the last mission of the Space Shuttle Atlantis. See image below.
The crew Dragon is currently scheduled for an unmanned test launch on the 23rd of February but has already been delayed several times. The mission will replicate a typical crew transfer mission to the International Space Station (ISS) with the exception of any crew to transfer. If the unmanned test is successful then a manned mission is planned for sometime in the second half of 2019.
Both the Space X Dragon and Boeing’s Starliner man capable capsules are part of NASA’s commercial crew program whose intent is to allow NASA to concentrate on pushing the frontiers of space outward while private companies like Space X and Boeing take over the now routine task of getting personnel and cargo to and from low Earth orbit (LEO).
The Starliner’s first unmanned test flight is now scheduled for sometime in March with a first manned mission before the end of the year. NASA is depending on one of these two systems to be successful, their current contact with the Russians to take American’s to the ISS runs out at the end of this year.
And speaking of space stations the ISS may have a companion in just a few years, a privately owned space station. A California company named Orion Span had just released detailed interior views of their proposed Aurora Space Station, which the company plans on launching into an LEO sometime in 2021, and be ready to receive occupants the following year.
Now Orion Span is advertising the Aurora station as a space hotel where guests will be able to enjoy both zero gravity and the sight of 16 sunrises and sunsets every day. Despite the fairly cramped quarters, the Aurora measures 13.2 m in length with a diameter of 4.2 m with a pressurized cabin space of 157 m3, the station will support four guests along with two crewmembers.
At a price of $9.5 million USD for a 12-day stay, price not including getting to and from the ‘hotel’, only the very rich will be vacationing there. However Orion Span also expects to welcome astronauts from small nations seeking to start a manned space program of their own, at a reasonable cost. According to Frank Bunger, founder and current CEO of Orion Span “We will support zero gravity research, as well as space manufacturing.”
Present plans for the Aurora station are modular in design to make assembly in orbit simple as well as to allow for further growth in time. And only time will tell whether or not the Aurora space station is actually placed into orbit in 2021, or indeed ever.
Before I go I would like to give a brief update on my Post of the 2nd of January about the New Horizons space probe’s flyby of the Kuiper belt object named Ultima Thule. The probe is still sending back the data it gathered during its New Year’s Day encounter, and will be doing so for almost the next two years.
However last week New Horizons did send back a much sharper image of Ultima Thule, see below.
The planetary scientists are The Jet Propulsion Laboratory (JPL) are going to be very busy analyzing the data as it comes back from the edge of the solar system, and I’m certain they’ll be enjoying every minute of it.
Why is it that journalists reporting on a science story so often feel compelled to generate a headline that exaggerates if not actually fabricates a catastrophe that we cannot avoid and will be lucky to survive. Then when you read the story you find out that the danger is something that may not happen for the next thousand or more years, or maybe not at all! The worst part is that the story itself may be very interesting, you just feel cheated because of the alarmist headline.
The latest such doomsday inexorably coming towards us is a collision between our Milky Way galaxy and the Large Magellanic Cloud (LMC), the Milky Way’s largest and best known satellite galaxy, see image below. A recent paper from Durham University’s Institute for Computational Cosmology indicates that the LMC is loosing energy as it orbits the Milky Way and it is only a matter of time before the cloud is devoured by the larger galaxy.
Because the it can only be seen from the southern hemisphere the LMC isn’t as well known as some of the constellations seen in the northern hemisphere such as the Big Dipper, Orion or Cassiopeia. In fact the LMC is a much larger object about 14,000 Light-years in size and having a mass of some 10 billion times the mass of the Sun, making it about 1/100th the mass of the Milky Way!
Now the news articles go on to describe in chilling details the destruction that could result from the collision including entire solar systems, maybe even ours, being hurled into the emptiness of intergalactic space. And those that remain behind won’t be spared either, for the supermassive black hole at the center the Milky Way will be reawakened as an active galactic nuclei, better known as a quasar, spewing extremely powerful jets of radiation into space.
Now before you panic the Milky Way is really big, about 100,000 light years across. This means that light itself would take 100,000 years to cross it so any other event, like a collision with the Large Magellanic Cloud, is going to take many thousands if not millions of years to have any actual effect. In fact the authors of the study, Carlos Frenk and Marius Cautun estimate that the collision between the LMC and our galaxy will not even occur for another two billion years!
More interesting is the idea that such collisions are actually common occurrences throughout the universe, astronomers have observed many of them with their telescopes, see image below. In fact there are several different theories of galactic evolution that assume that mergers and adsorptions are the driving force of change generating the different types of galaxies we see.
In fact it is probably such collisions that produce the well known spiral arms that many galaxies possess. Looking at the image below of the famous Whirlpool Galaxy you might think that the galaxy must be rotating in a counterclockwise direction because of the way the spiral arms curve. Actually the spiral arms have no bearing on the direction of rotation of the galaxy. They are in fact pressure waves set up by a collision with a smaller galaxy that appears as a bright blob on the right hand side outside the whirlpool proper. In a sense the collision has caused to whirlpool galaxy to ring like a bell!
Collisions between galaxies are actually some of the most titanic events in the entire universe, involving hundreds of billions of stars but they also take place very slowly, over billions of years. Because of this they can hardly be considered dangerous to creatures as short lived as we poor humans, no matter how hard some reporters might try to make that seem!
Before I go I’d like to take a moment to update a story I discussed in my post of only a week ago ( see post of 19 January 2019). One of the stories in that post concerned scientists who had learned the secret of the massively expanding slime balls produced by hagfish as a defensive mechanism. Then, just a few days ago I came across another story about the best ever preserved fossil of a hagfish that been found by paleontologists at the University of Chicago. See image below.
Hagfish rarely fossilize because instead of true bones their skeleton is made of softer cartilage. The fossil of the hagfish was positively identified by the chemical traces of keratin around the fossil. Keratin is a major component of the hagfish’s slime.
Of course it’s just a coincidence that the two, unrelated stories should occur within a couple of weeks of each other. Nevertheless it does illustrate how science serves as a framework to link and support the work of scientists around the world as they seek to learn the secrets of the universe.
In July of this year we shall celebrate the 50th anniversary of the first time human beings set foot on the Moon. July 21st 1969 is a milestone in human history and so to commemorate the event Science and Science Fiction will publish a series of posts, one each month detailing significant incidents in the Space Race that ended with Neil Armstrong stepping off the ladder of the Lunar Module and making the first footprints in the Moon’s dust.
For this first installment I’ve decided to discuss the launching of the world’s first artificial satellites, the Soviet Union’s Sputnik and the American Explorer. It was the launching of these two space probes that not only triggered the space race but set the pattern of how the first half of the race would develop.
It all started with the International Geophysical Year or IGY. What’s the IGY you ask? Well in 1956 the cold war between east and west had quieted down a little bit, enough that scientists in the soviet bloc were allowed to attend scientific conferences and actually talk to western scientists. To try to strengthen this period of cooperation it was decided that during the period from July 1st 1957 to December 31st 1958, you’ll notice that’s actually a year and a half, scientists across the world would work together to study the planet Earth. The subjects that would be covered included the aurora, cosmic rays, the planet’s magnetic field, meteorology, oceanography and seismology. As a part of the IGY the United States announced that it would attempt to launch the first artificial satellite into Earth orbit.
The Soviet Union beat them to it, launching Sputnik, which means fellow traveler, on October 4th 1957. The Soviet’s chief rocket engineer, Sergei Korolev had succeeded in developing the first Intercontinental Ballistic Missile (ICBM), a monster rocket called the R-7. The R-7 was much larger than anything the Americans had and gave the Russians a huge initial advantage. In fact the R-7 is still the basic design of the rocket the Russians use today to launch their Soyuz manned spacecraft.
Sputnik itself was a very simple satellite, a sphere 58cm in diameter with a mass of 83.6 kg. Sputnik carried no scientific instruments of any kind but only a radio transmitter broadcasting on 20 Mega-Hertz (MHz) and 40MHz. This allowed it to be picked up by radio amateurs around the world as it circled the Earth every 98 minutes. Sputnik completed some 1400 orbits before January 4th 1958 before it reentered the atmosphere and burned up.
Now the US intelligence agencies, i.e. the CIA, were aware that the USSR was working on large rockets so they were surprised but not shocked by Sputnik. President Eisenhower in particular was unimpressed. The American public however was thrown into a panic to think that the Soviet’s were ahead of them, that the Russians had rockets that could reach US soil.
Following Sputnik the US effort to place a satellite in orbit started to receive a lot more press coverage, a trend that would continue right up to the Moon Landing. What had been a scientific experiment now become America’s effort to show that they weren’t behind.
The satellite America intended to launch was called Vanguard and would have been a much more sophisticated. The Vanguard satellite would be powered by solar cells and in addition to a radio transmitter it carried a temperature sensitive crystal to perform measurements in out space. The Vanguard program had been chosen over the US Army’s competing Explorer program mainly because the rocket that would launch it was a civilian designed sounding rocket not intended for military use.
Unlike the Russians, who only announced a launch after it was a success, there was live TV coverage for the launch of Vanguard on December 6th 1957. The rocket rose only a few meters before the engine cut off and the whole thing came crashing back to Earth in an enormous fireball. Watching the explosion the panic within the US public really took off.
Meanwhile the Russians had launched Sputnik 2, with a live animal on board, a little stray dog from the streets of Moscow which was given the name Laika. According to Soviet press at the time Laika lived for a week in space. It wasn’t until the collapse of the USSR that the truth came out. Sputnik 2’s cooling system immediately malfunctioned and Laika had died within a half an hour of launch. Still, the second Sputnik only increased America’s feeling of impotence.
With the failure of Vanguard the US Army was quickly told to go forward with Explorer. This decision pleased Werner von Braun, the German rocket engineer who had developed the V-2 rocket. Coming to America after the war von Braun had worked for the US Army developing the Jupiter Intermediate Range Ballistic Missile (IRBM) from the V-2 design. von Braun had actually been ready to launch a satellite for several years but political considerations had caused the US to proceed with Vanguard.
The satellite for the Explorer program had been developed by Doctor James van Allen at the Jet Propulsion Laboratory (JPL) and consisted of a cylinder 205 cm in length by a little over 15 cm in diameter with a mass of 14 kg. Despite being smaller and less massive than Sputnik, Explorer was loaded with instruments including a radiation detector, five temperature sensors and two micrometeorite detectors. The reason Explorer was able to cram more science into a smaller volume than Sputnik was that it employed a brand new technology, 29 Germanium transistors made up a large part of the satellite’s electronic circuitry. The data from the instruments aboard Explorer were then relayed to Earth by a radio operating on 108 MHz.
Explorer was launched on the 31st of January in 1958 to the relief of the American people. It was the instruments onboard Explorer 1 that made the first actual discovery of the new space age as Doctor van Allen used the measurements of the radiation detector to recognize that there was a cloud of radiation surrounding the Earth. Later it was realized that there were several such bands of radiation which were christened the van Allen belts.
As I mentioned above the launch of both Sputnik and Explorer set a pattern that lasted throughout the first half of the space race. During the period 1957 to 1964 the Soviets scored a number of firsts in space but they never announced their missions until they were successfully launched. Their failures, which did occur, were simply never mentioned.
The Americans always seemed to be playing catch up and their failures were on display for the entire world to witness. Nevertheless the Americans always seemed to be able to do more with less, launching smaller satellites that made more discoveries.
The space race was on, at the moment it didn’t even have a finish line but it did have two very determined contestants.
I’ve come across three stories recently that illustrate nicely not only the wide diversity of life here on Earth but how much more there is for us to learn about it!
I’ll start with what is probably the most familiar type of animal, and location, salamanders in Texas. A team of naturalists led by Tom Devitt, an environmental scientist with the City of Austin’s watershed protection department, has recently discovered three new species of salamander.
Now most of Texas is dry and rocky, not the sort of environment you think of when you consider amphibians. However running through the south central portion of the state is the Pedernales River and the porous limestone bedrock of that region is crisscrossed with a network of caves and flooded channels known as the Edwards-Trinity aquifer system.
This system is the home of a wide variety of subterranean aquatic species. Many of these creatures are the descendants of ocean living creatures that inhabited the region in the cretaceous period when Texas lay at the bottom of a vast inland sea that stretched as far as the Canadian border. See map below.
Like many types of cave dwelling animals the salamanders discovered by the naturalists are very pale in colouration, lack eyes and possess flattened heads. Searching the twists and turns of these caves and channels isn’t easy so it understandable that these three small animals could have remained unknown for so long. Indeed it is quite likely that other species are still there waiting to be found.
The creature in our second story is probably not as familiar to most people as salamanders are. They are known as Hagfish and are one of the most primitive forms of vertebrates. Hagfish are such ancient creatures that their skeletons aren’t even made of bone but like sharks and rays they are composed of cartilage. Unlike sharks however, hagfish don’t even possess jaws but instead rely on a raspy tongue to scrape away at their food.
Hagfish are best known for possessing a remarkable defense mechanism that protects them from large predatory fish like sharks. Any creature that tries to take a bite out of a hagfish gets a little ball of mucus in their mouths that in less than a second expands about 10,000 times in volume, choking the hagfish’s attacker and allowing the hagfish to escape!
Scientists have been interested in the hagfish’s mucus for a long time, any material that can expand so much so quickly will certainly attract a good deal of attention. What scientists learned was that the most active part of the mucus is a very large number, many thousands of tightly coiled threads called skeins. See image below.
An individual skein measures only about 100 μm in diameter but once the thread is unraveled it can measure as much as 10cm in length, which accounts for the great increase in size of the mucus. See image below. Despite all that scientists had learned however the speed with which the threads unraveled remained unexplained. Speculation was that some unknown chemical reaction was responsible.
Now however Gaurav Chaudhary and Randy H. Ewoldt at the University of Illinois’ department of Mechanical Science and Engineering along with Jean-Luc Thiffeault at the University of Wisconsin’ department of Mathematics have determined that the hydrodynamic motion of the water itself is sufficient to uncoil the skein without the need of any chemicals.
Doctors Chaudhary and Ewoldt began by undertaking a detailed and precise examination of how the skein unravels while Doctor Thiffeault concentrated on the mathematics of the interactions between the uncoiling skein and the agitation of the water. Computer simulations indicate that nothing more than turbulence can result in the full expansion of the mucus.
Understanding the mechanics of a material that can expand thousands of times in volume could be of great importance in many engineering problems. The future will show if the hagfish’ defense mechanism can be reproduced and applied by human engineers.
My final story deals with a very common, yet small and largely unfamiliar creature formally known as Chaetognaths (The word means Bristle Jaw) but more commonly referred to as Arrow Worms. See image below. Living in environments ranging from brackish water to the floor of the ocean depths Chaetognaths comprise some 120 living species of predatory worm ranging in size from 2 to 120 mm.
Biologists have long been puzzled by Chaetognaths, unable to decide exactly where on the tree of life their small branch lies. Traditionally arrow worms had been placed near the flatworms, segmented worms and molluscs but in fact there was even debate as to which supergroup of animals the Chaetognaths belonged, the protostomes or the deuterostomes.
Now both protostomes and the deuterostomes share a common body plan with a single intestinal system running through them. The difference lies in which opening forms first, in protostomes the mouth forms before the anus while in deuterostomes it is the anus that forms first. Vertebrates are protostomes by the way while insects are deuterostomes.
To clear up the mystery a group of biologists from around the world led by Ferdinand Marle’taz of the Okinawa Institute of Science and Technology Graduate University (OIST) Molecular Genetics Unit have completed a detailed studied of ten species of arrow worm and compared them to other animals.
The results of the study clearly showed that Chaetognaths belonged with in protostomes but were not closely related to the other worms or molluscs. The closest relatives to arrow worms appear to be the tiny, often microscopic freshwater animals known as rotifers. See image below.
While the study by Doctor Marle’taz and his colleagues appears to have resolved some of the mystery of arrow worms there remain plenty of other questions to be answered as we learn more and more about the other creatures with which we share our world.
For the past three centuries both physicists and geologists have been studying the Earth’s magnetic field trying to learn its secrets, and to be honest there’s still a great deal that they don’t know. They do know that the field is generated by the rotation of our planet’s liquid core, although precisely how is fuzzy. They also know that the magnetic poles swap positions every 200,000 to 400,000 years although why is still a mystery. Now let’s be fair though, it isn’t easy to study a phenomenon that is hidden from you by 2,000 kilometers of solid rock!
I’ve spoken before about the possibility that the magnetic poles may be in the initial stages of flipping; see my post of 8Feb2017. Now there is further evidence that the process may be starting. The location on Earth’s surface where the North Magnetic Pole pops out of the ground is moving at an accelerated speed and in an unpredictable direction.
For more than a century the North magnetic pole had been firmly positioned in northern Canada, a full 700-800 km from the physical North Pole. Now it’s been long known that the magnetic poles move slightly, a kilometer or two every year, but in the last 40 years the speed of that movement has been increasing year by year. Researchers estimate that the speed of the north magnetic pole has reached 55km per year, see map below.
As you can see from the map the north magnetic pole has in the last 20 years actually been getting much closer to the real North Pole, although if it keeps moving in its current direction it will soon start to pull away again. If the magnetic pole continues to move in its present direction it will enter the Siberian region of Russia within several decades.
Theorists are speculating that a high-speed jet of liquid iron deep beneath Canada may be causing the rapid movement. Another idea is that there are two jets, one each beneath Canada and Siberia and a tug of war between them is to blame for the increased speed with which the magnetic pole is moving. In either case the movement is starting to interfere with worldwide navigation systems.
Think about it, humans have used magnetic compasses for centuries as an aid to navigation and even today’s advanced GPS location networks still depend on knowing just where the north magnetic pole is. By the way in case you didn’t know it you smartphone contains a magnetometer for detecting the Earth’s magnetic field, your map app wouldn’t work without it.
In order for these computerized navigational systems to work accurately every five years scientists have been updating the ‘World’s Magnetic Model’ with the latest, precise location for the north magnetic pole. This model has been maintained by both the US Nation Oceanographic and Atmospherics Administration (NOAA) and the British Geological Survey. The next update is due in 2020 but because the north magnetic pole is moving so fast that update is needed right now.
There’s a problem however, because of the government shutdown in the US brought on by the fight over Donald Trump’s border wall the scientists at NOAA who work on the world’s magnetic model aren’t working on anything. They’ve been put on furlough until the impasse ends, whenever that may be. Meanwhile the navigational systems that our modern society depends on are slowly becoming more inaccurate as the North Magnetic Pole continues to move.
You hear about Genetically Modified Organisms every now and then on the news. Usually referred to as GMOs they are generating a great deal of excitement among biochemists and the food industry while causing just as much fear in some parts of the general population.
In a sense we have been modifying living creatures for 10,000 years. Starting with wolves we selectively bred them to enhance the characteristics we desired until we got man’s best friend the dog. Using the same techniques human beings have selectively bred hundreds of species of plant and animal to give us pretty much all of the food we, and our selectively bred pets, eat!
Selective breeding is genetic modification from the outside however. It’s only over the last 30-40 years that biochemists have been able to go straight to a living creature’s DNA and directly modify it. And it’s only in the past five years that scientists have possessed the precise and efficient gene-modifying tool known as CRISPR. (See my Posts of 5Aug17, 1Sept18 and 1Dec18 to learn more about CRISPR and how this gene-editing tool works).
Using CRISPR biochemists hope to modify the plants and animals we eat in order to make them to grow larger more quickly, while requiring less fertilizer or feed. This would of course make food both cheaper and more abundant and in a world where more than 10% of the population goes to bed hungry that has to be a good thing.
One study could be a real game changer in the effort to produce more nourishing food. Researchers at the University of Illinois have been able to genetically modify the biochemical factories of plants in order to dramatically increase the efficiency of photosynthesis itself.
You’ll recall that photosynthesis is the chemical process by which plants use sunlight to convert carbon dioxide and water into sugars. In fact photosynthesis is the basic chemical reaction by which all of the world’s food is produced! Photosynthesis is rather inefficient however; it is chemically unable to distinguish between a carbon dioxide and oxygen molecules. According to plant biologist Donald Ort, the study’s senior author, “This is essentially anti-photosynthesis, and the plant produces a toxic compound that it has to recycle and detoxify.”
The researchers modified the DNA of Tobacco plants to simplify and speed up that detoxifying process resulting in plants that grew larger much more quickly, see image below. Dr. Ort and his team choose tobacco plants as a test subject because tobacco grows quickly and possesses genes that are easy to manipulate. The results are certainly impressive with tobacco plants that are 40% larger than ordinary plants.
Having demonstrated the advantages of their approach the biochemists are now applying their technique to more useful plants like potatoes and soybeans. If this enhanced photosynthesis can be applied to other vegetable crops the resulting increase in food production could go a long way to helping feed the hungry nations of the world.
Some scientists are using gene editing to be a little more creative. One group wants to develop a spicy, peppery tomato. Now it turns out that tomatoes and peppers are pretty closely related, having split apart only about 20 million years ago. This means that the genes to produce Capsaicin, the chemical that makes peppers spicy, are still there inside a tomato’s DNA but according to co-author Agustin Zsögön they “are just not active.” Dr. Zsögön hopes to reactivate those genes allowing the humble tomato the ability to be as hot as any chilli pepper.
So why would scientists be so keen on developing a spicy tomato. Well the chemical capsaicin does more than just make your food taste spicy. Research has shown that capsaicin compounds are high in antioxidants; help the body fight cancerous tumors while aiding in both weight and pain management.
Right now the challenge is in determining which genes within the tomato to either turn back on, or turn off in order to get tomatoes to start producing capsaicin. Still, in a few years you may not need that habanero pepper in order to put some heat in your recipe for enchilada sauce!
Whether we use gene editing to greatly increase food production or just put a little more spice in our meals there are going to be people who are concerned about what other, unintentional chemicals we may be putting in what we eat. The workings of DNA, and the processes by which it controls the growth of cells are still largely unknown. The fear is that by modifying the genes of organisms to make them produce more food, we may also cause them to produce poisons or other deadly chemicals.
The scientists working on gene editing techniques are aware of this problem. As Dr. Ort says, “…any enhanced crops would undergo rigorous testing before they are ever consumed by humans.” Scientists like Dr. Ort may be determined to go slowly and test completely but what about large food corporations who are determined to both keep costs down and get their new products on the market before their competitors do. And not all the scientists are as trustworthy as Dr. Ort. Remember Chinese scientist He Jiankui who just two months ago revealed that he had used CRISPR on human embryos!
Like every advance in science gene editing can either benefit the world or harm it. It’s up to us, all of us to decide which it will be.