Bit by bit Astronomers are learning the secrets of the massive stellar explosions called Supernovas, even if they do occasionally come across evidence that doesn’t fit their theories.

Everyone has heard a little bit about Supernovas, you know those stars who destroy themselves in explosions that for a few weeks can outshine many billions of normal stars. Supernovas are very rare events, happening only every couple hundred years in our galaxy of one hundred billion stars. In fact supernovas are so rare that most of what we’ve learned about them comes from observing ones that happen in other galaxies. It works like this, if supernova only occur once every 100 years per big galaxy then if you keep an eye on 1,000 galaxies you should see about 10 a year!

Three images, taken on successive nights, of the Galaxy M101. On August 22 (l) there was no supernova, green arrow shows location. SN2011fe was discovered on the night of the 23rd (m) while by the night of the 24th (r) it was considerably brighter. By keeping an eye on a thousand such galaxies astronomers manage to observe a dozen or so supernova ever year. (Credit: Space.com)

The very first studies of supernovas, conducted more than 70 years ago now, used spectral analysis to show that there were two basic types. One type, not surprisingly called Type 1, had virtually no hydrogen in the spectra obtained from their light. Now hydrogen is the most common element in the Universe so for Type 1 supernovas to be completely lacking in it is really significant. Type 2 supernovas are just the opposite, their spectra shows plenty of hydrogen. One thing both types have in common is that they are very rare which indicates that only a small percentage of stars ever go supernova.

In time astrophysicists came up with two rather different models of supernovas. Type 1 begin with a white dwarf, the superdense corpse of a once normal star, for example our Sun will become a white dwarf in about 6-7 billion years when it runs out of its hydrogen fuel. A typical white dwarf has a mass about that of our Sun but its size is only that of the Earth. The surfaces of dwarfs are extremely hot but because of their small size they are much dimmer than a normal star like our Sun.

If a white dwarf star steals mass from a companion star it can grow too massive leading to a collapse that triggers a Type 1 Supernova. (Credit: Phys.org)

Now if a white dwarf happens to have a companion star, and there are many examples of binary star systems, the dwarf can start pulling material away from its companion. This stealing of matter can only go on so long however because there is a maximum limit to the mass of a white dwarf. This maximum mass is about 1.4 times the mass of our Sun and if a dwarf exceeds this limit it begins to collapse triggering the Type 1 supernova. After the explosion all that’s left of the star is a neutron star or even a black hole.

The famous Crab Nebula M1 is the remains of a Type 2 Supernova. At the center of the nebula is a neutron star that emits radio signals as a pulsar. (Credit: Wikipedia)

Type 2 supernova however start as huge, very massive stars, at least ten times the mass of the Sun. The fusion reactions in such stars use up their hydrogen fuel in only a few million years. The star will then begin to fuse helium into carbon and oxygen, which is as far as our Sun will ever get. Massive stars however have enough energy to keep going, fusing carbon and oxygen into heavier elements all the way up to iron.

The supermassive star Eta Carinae, seen here in an image from Hubble, is destined to explode in a few million years as a Type 2 supernova. (Credit: Medium)

Iron is a brick wall however, fusing iron into a heavier element doesn’t produce energy it consumes it. The fusion reactor of this huge, massive, intensely hot star suddenly comes to a screeching halt and the star begins to collapse upon itself. This collapse triggers the supernova but unlike a Type 1 supernova there is still some hydrogen left in the star’s outermost regions, which shows up in the explosion’s spectra. After the explosion all that remains of the star is a neutron star or black hole.

Nuclear binding energy per nucleon. Nuclei that are less massive than iron can be fused to produce energy while more massive than iron can be split to produce energy. Whatever you do to iron however will require energy. (Credit: Conceptual Physics)

Those are the theories, but to be certain they’re right we would have to observe a star before it goes supernova and that’s not an easy thing to do. After all there are literally trillions of stars in our galaxy and nearby ones, while only a couple of dozen of those stars will go supernova each year. The question is then, which ones? Well what astronomers have tried to do is to get observations of as many stars as possible. Then when a supernova does occur they check their archives to see if they have any prior images of it.

The star Sanduleak -69degrees 202 (r) before it exploded as SN1987A (l). This was the first time astronomers were able to identify the progenitor star to a supernova. (Credit: David Malin, Anglo-Australian Observatory)

The first time that this technique worked was the Type 2 Supernova SN 1987A, in the Large Magellanic Cloud, which is a satellite galaxy orbiting the Milky Way. Almost as soon as SN 1987A was detected astronomers quickly began looking through their past observations and succeeded in finding a few observations of the star, catalog name SK-69º202 before it exploded. Although there were a few surprises SK-69º202 turned out to be pretty much what astronomers had expected, with 15 times the mass of our Sun and a very hot surface. The data gained from SN1987A taught astrophysicists a great deal about Type 2 supernovas, but of course they wanted more, and in particular, they wanted a Type 1 supernova progenitor.

SN 2019yvr in the galaxy NGC 4666 at a distance of 46 million light years. (Credit: Remote astrophotography using Slooh.com)

Now they may have one, and it’s not what they expected. Back in December of 2019 astronomers spotted a supernova, designated SN 2019yvr in the galaxy NGC 4666 which is about 46 million light years away in the Virgo super cluster of galaxies. Even as observations were showing that SN 2019yvr was a Type 1 supernova astronomers associated with the Hubble Space Telescope were rummaging through earlier images of NGC 4666 to try to see if Hubble had ever made any observations of the star.

The Hubble space telescope has made many discoveries during its lifespan. The image of the progenitor star for SN2019yvr may be its latest. (Credit: Science Focus)

The astronomers spent more than a year of checking and crosschecking between the measurements made after the supernova began to those that had been taken earlier. Nevertheless they think they may have found the supernova’s progenitor in a series of images taken some 2.6 years before the explosion, problem is, the star they’ve identified is not the kind the theory says it should be.

Instead of a tiny, dense, extremely hot white dwarf the star that’s been identified is a fairly cool orange-yellow star more than 300 times the width of our Sun. A star like that should have plenty of hydrogen left in it but the spectra of the supernova showed none, it’s just a mystery.

The type of star Hubble found however appears to be an Orange ‘K’ type star shown here with a larger ‘G’ type star, our Sun, and a smaller red ‘M’ type star. (Credit: EarthSky)

The astronomers have already come up with several explanations for the disagreement with the theory. First of all they could simply have identified the wrong star. They can’t check to make certain right now because the debris of the supernova is currently obscuring that region of space and it will take 5-10 years before they are able to see if the orange-yellow star is still there.

The expanding debris field of SN1987A makes it difficult to observe the remaining neutron star at the center. (Credit: CEA-Irfu)

Then there’s also the possibility that the companion star, remember Type 1 supernovas require a companion star, could have given off enough material to form a cool gaseous shroud around a white dwarf that was the actual supernova progenitor. Again checking this possibility will have to wait for the debris to clear a good deal.

Of course there’s also the possibility that our theories are just wrong and have to be adjusted. Whichever possibility turns out to be true astronomers are bit by bit learning the secrets of what are some of the most spectacular events in the Universe, Supernovas. 

Book Review: ‘Return to Enceladus’ by Brandon Q. Morris.

Anyone who has been reading my reviews of Science Fiction novels will surely have noticed a certain trend of late. I am getting rather tired of interesting ideas that produce a really good single novel being turned into an entire series of books. The second book in a series may still be worth reading but it will certainly be inferior to the first. And the quality of the stories really decreases after that.

Author Brandon Q. Morris. (Credit: Mal Warwick on Books)

A case in point is the ‘Ice Worlds’ series by the author Brandon Q. Morris. The first novel ‘The Enceladus Mission’ was a good hard SF story about an unmanned probe discovering signs of life on Saturn’s moon Enceladus. A manned expedition aboard the space ship ILSE (which stands for International Life Search Expedition) is sent to both confirm the discovery and learn more about the life forms.

Cover of ‘Return to Enceladus’ by Brandon Q. Morris. (Credit: Amazon.com)

The description of ILSE was quite realistic and the entity on Enceladus was both different and intriguing, it was sort of one of those ‘group mind’ aliens that appear in some SF novels. All in all ‘The Enceladus Mission’ was a good book that I still recommend.

‘The Enceladus Mission’ was a good ‘hard SF’ novel with an interesting alien. (Credit: Audible.com)

The second novel ‘The Titan Probe’ also wasn’t bad. With the ILSE and her crew already at Enceladus the idea of them taking a little side trip to Saturn’s biggest moon Titan made sense and again the life form that they found there, if not as well described as the one on Enceladus, was at least interesting and different. One part of ‘The Titan Probe’ needs to be mentioned. During the story, one of the ILSE crew, the ship’s doctor Marchenko sacrifices himself to save several other crew members but his consciousness is implanted on the ship’s computer by the entity on Enceladus.

The possibility of life on Enceladus has engineers and scientists at NASA already planning for a mission to probe beneath the icy crust of the moon of Saturn. (Credit: Parabolic Arc)

The third novel ‘The Io Encounter’ was a real disappointment. The crew of ILSE are on their way back to Earth when they’re ordered to stop off at Jupiter’s moon Io. Again signs of life have been found there. And while most of the crew are on Io’s surface the ILSE turns back toward Enceladus only to stop halfway there and return to Io!

Jupiter’s moon Io is squeezed and stretched by the immense gravity of Jupiter. This makes Io the most geologically active body in out solar system and hardly a place to find life. (Credit: Astronoo)

All this is completely unrealistic; space missions are planned out years in advance and are simply not equipped for any major changes in trajectory. Having actually calculated a couple of, admittedly rough, space missions I know very well how a side trip another planet is rarely possible. Jupiter could be on the other side of the solar system from Saturn for example, and such changes in the mission would require double the amount of fuel if not much more. In fact the delta Vee needed to go into orbit around Jupiter is really enormous. What had started as a believable SF story had become little more than a cartoon where the laws of physics are ignored. Worse yet, the quality of the story had also suffered.

The starship Enterprise may be able to change course for a new destination at the orders of Captain Kirk but real spaceships require years of planning to accomplish their missions. (Credit: Popular Mechanics)

The fourth novel ‘Return to Enceladus’ is no better. The crew of ILSE are back home on Earth where they get a proposal from an eccentric Russian billionaire who wants them to go back to Enceladus. He is making money by mining near Earth asteroids and is looking to expand his business to the outer solar system. The crew’s reason for going back would be to retrieve the body of their dead comrade Marchenko so that his consciousness can be reinstalled; no description of how this will be done is ever given.

The idea of mining an asteroid has become a common idea in SF stories. It’s probably going to be harder than most people think. (Credit: ExplainingTheFuture.com)

Problem is that the ILSE has been left on a course that will take it to be destroyed in the Sun so the first thing the crew, now joined by the Russian’s daughter, have to do is take one of his ships to rendezvous with the ILSE and stop it from plunging into the Sun. Once on board they set course for Saturn, no mention is made as to how the ship is refueled or resupplied with enough food for a two-year mission.

The idea of downloading a human consciousness onto a computer is also quite old an old one. (Credit: Live Science)

At this point the story becomes a mystery novel as several attempts are made on the lives of different crewpersons and the mission itself. Actually the guilty party is pretty obvious from the start but the crime plot still it takes up half the novel. And when we finally get back to Enceladus the entity there has gone into hiding, it’s now afraid of us, so we don’t even learn more about it.

I have to admit I’m not a fan of murder mysteries in general and adding one to a SF novel is just not a good idea. (Credit: Illinois River Road)

Anyway the whole trip wasn’t worth it in my opinion. The ‘Ice Words’ series by Brandon Q. Morris is just another series of novels that starts out as being fresh and interesting but by the end has just simply run out of steam. ‘Return to Enceladus’ just isn’t a very good SF novel.

Over the next few weeks Pennsylvania and other eastern states will be overrun by billions of Periodic Cicadas, sometimes known as the 17 year Locust.

Our planet is home to more than a million different species of insect, all of whom seem strange and alien to we humans. There are some species however whose lives are unusual even compared to those of other insects and somewhere near the top of that list must be the periodic cicada. Cicadas are those beautiful but noisy creatures who seem to vanish for several years and then suddenly appear by the millions for only a few weeks in the spring.

The number and diversity of Insects is simply overwhelming. The number of different species must number well over a million, every one unique in their own way. (Credit: Britannica)

Cicadas are a large and widespread group of insects numbering over 3000 species worldwide. With large eyes set far apart and membranous front wings cicadas mainly live by sucking the sap from the trees in which they typically live and where they lay their eggs. Cicadas are also known by the loud drumming noise made by the male that is used as a mating lure and produced by rhythmic vibrating of their body.

The 17 year cicada is notable for it large red eyes spread far apart. (Credit: NPR)

One genus of cicada native to eastern North America lives virtually its entire life underground as immature nymphs feeding off the sap in the roots of trees. These species only metamorphose into adults and emerge from the soil in order to breed. In fact these adults usually lack a mouth and digestive systems and are therefore unable to consume nourishment in any way. Some species, known as annual cicadas remain underground for 7-9 years typically with a fraction of the nymphs emerging every year in order to breed.

Difference between an annual (r) and periodic (l) cicada. Annual cicadas actually live for about 7-9 years but most of that is spent below ground and a fraction of the species mature as adults every year. (Credit: IndyStar)

Strangest of all are the periodic cicadas; members of the genus Magicicada who remain underground for either 13 or 17 years and who then emerge by the billions. In each of these types there are several broods centered in different parts of the country and this is the year for one of the biggest, Brood X of the 17 year cicada.

Map showing locations of the various broods of periodic cicadas. Brood X is in yellow! (Credit: Vox)

Biologists have been hotly debating the evolutionary reason behind such an unusual life cycle for a long time, especially the question of how the prime numbers 13, and 17 became the most common time frame. One argument is that by suddenly appearing by the billions the cicadas, who have absolutely no means of defense, simply overwhelm their predators with sheer numbers. Insect eating birds and other animals can consume their fill and there will still be billions of cicadas left to produce the next generation.

Mayflies are another kind of insect that practices predator saturation coming out as adults for only about a week or so they appear in the billions so that some manage to mate before they’re all eaten. (Credit: CNN)

This strategy is known as ‘predator saturation’ and the reason for the prime number of years in the cicada’s lifespan is that it makes it harder for a predator species to synchronize their own breeding to that of the cicadas. For example if the cicadas emerged every four years then Blue Jays or Crows might be able to evolve to lay more eggs every four years, producing more offspring during the years of cicada breeding so as to take advantage of the extra bounty available to feed their own young. Some researchers also think that the long period timing may have developed during the ice ages when living underground may have been a considerable advantage.

Did periodic cicadas evolve their strategy of living underground for years in order to avoid the worst of the ice ages? (Credit: History.com)

Either way there is now evidence that global warming may be affecting the timing of some individuals within each brood. You see biologists think that cicadas keep track of how long they’ve been underground by counting the number of times that tree sap starts rising from the roots into the tree proper. Thanks to global warming over the last few decades the eastern US has had several ‘false springs’ where it got so warm in January or February that some trees started to sprout only to have a later frost put an end to the early growth. Did some cicadas count those false springs as an extra year? Well, what is known is that a small number of Brood X cicadas emerged in 2017 in the area of Washington D.C., four years too early.

Like with so much else there is evidence that global warming is affecting the lifestyle of the periodic cicada. (Credit: Environmental Protection)

Cicadas have been around since at least the Permian period however, and with thousands of species and many billions of individuals they could very well outlast the human race.

Fossil of a cicada from the Jurassic period. They’ve been here a lot longer than we have!!(Credit: Scientific American Blogs)

So if you live in along the US east coast between Pennsylvania and Georgia and as far west as Indiana keep your ears listening this spring, it’s usual to hear cicadas before you see them remember. If you do you may encounter one of the strangest and wonderful of Earth’s living creatures, the 17 year cicada.

Archaeology news for May 2021, three stories that come from areas of the world not usually considered archaeological ‘hot spots’.

Ever notice how just a few places on Earth get all of the press coverage when it comes to evidence of ancient civilizations. Egypt of course heads the list closely followed by Greece, Mesopotamia and Central America. Then there are certain specific ancient sites that gather a lot of attention like Stonehenge or China’s terra cotta warriors. Media coverage of archaeology is minimal at best and news directors aren’t going to give precious airtime to a story from some part of the world that the average viewer doesn’t associate with archaeology.

I don’t known about you but it seems to me that anytime anything old is discovered in Egypt it gets massive press coverage while important discoveries made in out of the way areas of the Earth go almost unnoticed! (Credit: Archaeology Magazine)

Well I will! This month’s stories come from such far-flung places as Laos, the Arabian Desert and Ireland. (O’k maybe Ireland does have some well-known ancient sites like Newgrange along with a wealth of Stone Circles but this is the first time I’ve ever heard of an archaeological discovery coming from Laos!) Let’s begin with the remains that are considered to be the oldest, the mysterious mustatils of the Arabian Desert.

Aerial view of three Mustatils from the Arabian Desert showing something of the variations in construction and preservation. (Credit: Granthshala UK)

Mustatil is from the Arabic word for rectangle and they typically consist of a rectangular shaped stone enclosure as small as 20 meters to as long as 600m meters with sandstone walls averaging less than 1.5 meters in height. Over one thousand of these structures are known from the northwest corner of the Kingdom of Saudi Arabia.

Area of the Arabian peninsula where the Mustatils are found. (Credit: The Wild Hunt)

Excavations of several mustatils have revealed a chamber in the center of the enclosure that contained the bones of cattle and other animals such as sheep, goats and gazelle. Carbon-14 dating of the animal remains have given dates as far back as 5000-5300 BCE, more than 7000 years ago.

Ground level view of a Mustatil. Based upon the remains archaeologists are convinced that the walls of the enclosures were quite low, no more than 1.5 meters or so. (Credit: Eurasia Review)

The low height of the enclosure walls makes it unlikely that the mustatils were used as corrals and other signs indicate to archaeologists that the structures were used for ritualistic purposes. As such the mustatils may be the first evidence of a cattle cult in the Arabian Peninsula and in fact may represent the earliest known religious structures on Earth. Indeed the number and variety of animal remains at the mustatils are also evidence that thousands of years ago the Arabian Desert was a much more fertile grassland than they presently are.

Images of cattle are among the earliest art made by human beings. Are these images a sign of reference as well as beauty? (Credit: Pinterest)

Mustatils only became known to the scientific community in the 1970s and have still only been superficially studied. However the Saudi Royal Government has begun funding a project to carry out more thorough investigations. Part of those studies will be undertaking by the Aerial Archaeological in the Kingdom of Saudi Arabia Project (AAKSA) in the hopes of identifying and cataloguing all the mustatils.

By contrast the known archaeological sites of Ireland have already been rather thoroughly surveyed and any major new discoveries now rely on the chance unearthing of previously undiscovered remains. Just such a discovery occurred a month ago in April on the Dingle Peninsula of County Kerry as workmen who were making improvements to a farm unearthed a stone lined burial chamber known as a “cist”. The grave was discovered when the workmen were using a backhoe and overturned a large flat stone used to cap the tomb revealing what lay beneath.

View of the tomb discovered in County Kerry from above. (Credit: Live Science)

Fortunately the workers immediately notified National Monuments Service and the National Museum. An initial examination indicated that the grave was likely to date from the Bronze Age, around 2500 BCE and best of all, the entire site appears completely untouched.

Map of ancient burials discovered in Ireland. (Credit: JSTOR)

A small sample of the skeletal remains were removed and sent to a labouratory for carbon-14 dating and an unusual find of an oval shaped polished stone was discovered next to the body. There are also indications of an adjacent sub-chamber at the front of the cist. A full excavation is being planned and should commence soon. This region of Ireland is well known for its ancient burials so it is possible that further discoveries could be only a few meters away beneath the ground.

View of the inside of the Kerry Cist. The stone wall in the image center may cover the entrance to another chamber. (Credit: Live Science)

The stone Jars of the ‘Plain of Jars’ in the country of Laos may be easier to find but they are no less mysterious. In fact let’s be honest the entire country of Laos is pretty mysterious to most people. Aside from once being a part of French Indo-China and then an unwilling participant in the Vietnam War I know little this small land-locked country. So I was quite excited to hear about the archaeological research going on by the University of Melbourne and the Australian National University along with the Laos Department of Heritage in the northern part of the country.

Location of the Plain of Jars in Northern Laos.

The plain of jars is actually a series of eleven sites where massive containers carved from sandstone are spread haphazardly across the landscape. Site 1, the largest location contains over 400 of these jars many of which are 2 meters across. Rather than being used for storage these jars were used for mortuary purposes where a deceased person would be placed in a jar and exposed to the elements. Carrion birds and other wildlife would consume the flesh and after a month or so, when only the bones remained they would be removed and placed in a more permanent, usually family based internment.

Aerial view of dozens of the jars. Is the haphazard arrangement caused by different families grouping their jars away from other clans? (Credit: South China Morning Post)

 

Some of the individual jars are quite large and massive and must have required an enormous amount of work to transport and hollow out! (Credit: Hole in the Doughnut Cultural Travel)

This form of funeral practice was actually very common in ancient societies. The longbarrows in southern England have been found to contain the bones of hundreds of individuals stacked together. There are even cases where the skulls of the dead were placed together in one chamber of the barrow while the other bones were placed in adjacent chambers.

Typical English Long Barrow. The bones, and only the bones of hundreds of individuals could be laid to rest in such a tomb. (Credit: Photographers Resource)
Native American peoples practiced exposure of their dead. Once the flesh had been eaten by birds of prey the bones would be recovered and kept as memorials. (Credit: Native American Netroots)

The best theory for how the stone jars of Laos were employed follows much the same idea but there’s a problem. Chemical analysis of the soil beneath several of the jars indicates that they were placed in their current locations somewhere between 730 to 1350 BCE, around 3,000 years ago. However carbon-14 dating of some human remains buried near the jars give a much younger age of 800 to 1400 CE. Is it possible that the stone jars were used over such a long period of time? Or did a second, much later culture make use of the ancient jars that their distant ancestors had originally erected.

Evidence gathered at the sites of the Jars in contradictory. Chemical analysis of the soil says the jars have been there for as much as 3,000 years but remains found nearby say only about half that age. Just another mystery for a very mysterious place! (Credit: Live Science)

At least researchers have managed to identify where the stone for the jars came from. Chemical test have revealed that the stone came from a quarry just 8 km away. However, whether the stones were brought to the plain and then carved or carved first and then brought to the plain is unknown, as is the method used to move the stones, some of which weigh several tonnes.

We humans spread out across the face of the Earth thousands of years ago and so its not surprising that even the most isolated and little known parts of our world can still provide some archaeological mysteries worth studying.

What can cannibalistic moth caterpillars teach us about pacifism, turns out quite a lot!

Living creatures exhibit a wide variety of lifestyles, some of which to us can seem bewilderingly strange. Take the common pantry moth, also known as the Indian meal moth, biological name Plodia interpunctella. A frequent household pest P interpunctella lays its eggs in packages of flour, cereals and other dry goods. The caterpillar stage of the moth then lives by consuming some of the food in which it was born.

An adult Plodia interpunctella or Pantry Moth. (Credit: Pinterest)
The caterpillar stage of P interpunctella normally feeds on vegetable matter but can turn cannibalistic when it encounters another of its species. (Credit: BugGuide.net)

Normally a peaceful vegetarian when left alone, if two caterpillars of P interpunctella happen to come upon each other it can be a fight to the death with the victor literally eating its vanquished foe. And it doesn’t matter even if the two combatants are siblings the instinct to eliminate the competition, and acquire a little protein, just takes over. 

P interpunctella is a well known household pest causing a considerable amount of loss of stored food. (Credit: Adobe Stock)

Such violent behavior is instinctive, adapted for a normally solitary lifestyle. It can be asked therefore, under what conditions and how long a time would be required to change those instincts? Well, a team of biologists at Rice University in Texas and the University of California at Berkeley wondered about that and set up an experiment to answer those questions. Pantry moths caterpillars it turns out make good lab animals because they’re used to living in containers, their food is cheap and their lifespans are so short you can get a lot of generations in just a few years.

Since P interpunctella is both easy to grow and a well known pest it is often used as a lab animal. (Credit: Wiley online library)

In their experimental setup the researchers wanted to control the dispersion, that is the spatial spread that a brood of caterpillars could attain. They did this by establishing five separate habitats and varying the viscosity of the food in each. The less viscous the food the greater the caterpillars could spread out, the more viscous the food the more often a caterpillar would encounter a sibling.

What the biologists discovered was that over ten generations those caterpillars that were forced to remain in close quarters with their relatives showed a marked decrease in cannibalistic behaviour. According to Volker Rudolf of Rice University and one of the study’s authors. “Families that were highly cannibalistic just didn’t do well in that system. Families that were less cannibalistic had much less mortality and produced more offspring.”

The experimental setup used to alter the behaviour of P interpunctella caterpillars. (Credit: BigThink.com)

This result provides strong evidence for a theory advanced by Rudolf and co-author Mike Boots of UC Berkeley. Their idea is that when animals, not just pantry moths, interact with each other more the degree of cannibalism declines because the odds of eating your own sibling, who shares half of your genes, increases.

Whether these results can be applied to other species remains to be seen. Also it is worth noting that in the experiment the supply of food was not constrained, everybody had plenty of food to eat. In a situation where resources are severely limited eating a sibling might be the only way for anyone to survive!

Nature red in tooth and claw. Let’s be honest the natural world is a very violent place. (Credit: The Phrase Finder)
There are many examples of species that will eat anything, even their own kind! (Credit: All that’s Interesting)

However there is a growing amount of evidence that the instinct towards violence can be altered, and over the course of not too many generations. In my post of 11 December 2019 I discussed the work of Doctor Belyayev, a Soviet biologist who conducted selective breeding experiments with foxes. By breeding together those animals that appeared tamer Doctor Belyayev succeeded in only six generations in producing a strain of fox that was as tame as a domestic dog. At the same time Dr. Belyayev mated those foxes that seemed especially violent and again in only six generations produced a strain that was pathologically vicious.

Evgeny Belyayev playing with some of the foxes he had tamed by selective breeding. (Credit: The New York Times)

And in my post of 17 June 2020 I reviewed the book ‘The Better Angels of our Nature’ by Harvard Professor of Psychology Steven Pinker. That book considered in great detail the mounting evidence that living in a civilized society is actually making human beings less violent. In a sense all three of these sources point towards the same general theory, that under the correct conditions violent behavior can be greatly reduced if not eliminated from a population within an evolutionarily short period of time.

A quote from ‘The Better Angels of our Nature’ by Steven Pinker. Hope for the future? Perhaps? (Credit: Pinterest)

Of course there is still much more that needs to be learned. But it is becoming clear that we can learn how to control our violent animal behavior, if we can only find the will to do so.

Physicists use imaginary numbers all of the time to help them describe physical reality, but do they themselves have any physical reality?

We all remember square roots from our high school math classes. You know, since 3 times 3, formally 32 squared, equals 9 that means that the square root of 9 is 3. Some numbers, like 9 have nice round square roots like 3. Other numbers, have square roots that are irrational, that is the number never comes to an end and never repeats itself. The square root of 17 is 4.12310563… for example.

The study of ‘Perfect Squares’ is a branch of number theory in mathematics. (Credit: Socratic)

Negative numbers are a special problem because you’ll remember that a negative number times another negative number gives a positive number. Therefore -3 times -3 is +9, not -9. So what is the square root of -9? Does it even have one?

(By the way, if you’ve always had difficulty imagining why a negative times a negative gives a positive consider this metaphor. Someone films a bathtub while water is draining out of it. That film is then shown running backwards! The water draining out is a negative, running the film backwards is also negative but what you would see is the water rising in the tub. A positive!)

For along time mathematicians simply ignored the possibility of the square root of a negative number. Such things just don’t exist they said. Then a sixteenth century Italian mathematician named Cardan was trying to find two numbers that when added together equal 10 but when multiplied equal 40. The solution he got was:

Cardan himself wrote that his solution was meaningless, fictitious and imaginary. But it worked. It worked so well that mathematicians quickly figured out how to contain the madness as it were.

What they did was to define an imaginary number, i2=-1, not i= √-1, the number i is actually never defined, only its square is. Nevertheless anytime mathematicians came across a √-1 they would replace it with i. So for example √-16=√16*√-1=4*√-1=4i.

If you define the imaginary number i this way mathematicians will consider you poorly educated. (Credit: Wumbo)
This is the proper way to define i. (Credit: Kahn Academy)

Formally the square root of a negative number is called imaginary, like 4i, but a combination of an imaginary number and a real number is called a complex number, 5+4i would be an example where 5 is the real portion and 4 the imaginary part. All complex numbers have a strange counterpart called the complex conjugate where every i has its sign changed, i→-i and -i→i everywhere. Whenever a complex number is multiplied by its complex conjugate the result is always entirely real, for example taking the most basic complex number A+iB where A and B are both real numbers and i2= -1 the complex conjugate would be A-iB and:


The terms in i cancel each other out while the i2 term =-1. Since A and B are both real A2+B2 is totally real. For a time it was thought, or perhaps hoped would be a better word, that imaginary and complex numbers were just mathematical fictions, with no application in the real world. However it was found that the familiar trigonometric functions could be expressed as complex functions.

Physicists meanwhile were starting to use the sin and cos functions to represent waves of varying kinds, light waves, sound waves, alternating current in electrical systems etc. Things got even worse during the development of quantum mechanics when the wave nature of subatomic particles became evident and the solutions ψ(x,t) of the Schrödinger wave equation:

are always complex. It was physicist Max Born who figured a way out of this dilemma when he suggested that ψ itself is not observable, its only when ψ is multiplied by its complex conjugate ψ* giving ψψ*= real that the answer to the Schrödinger equation becomes an observable. Schrödinger himself considered the presence of all those i’s in his equation to be unpleasant writing to a fellow physicist that “ψ is surely a fundamentally real function.” This is where physics has remained now for nearly a century with the solutions to our equations giving complex answers but we only pay attention to the so-called ‘real’ part.

Complex numbers are a bit easier to understand, and are very useful, if you consider them as a 2-dimensional plane. The real part is along the x-axis while the imaginary part becomes the y-axis and the complex number as a whole becomes a vector! (Credit: TeX StackExchange)

Now a group of theoreticians has proposed a thought experiment wherein the reality of imaginary numbers is required and it involves another of quantum mechanics strange properties, quantum entanglement. The basic idea of quantum entanglement is that if you measure the state of two particles those particles are now entangled and even if you separate them the measurement of them as a system must remain the same.

Physicists are currently playing all kinds of games with the particles of light called photons in order to learn more about the phenomenon of quantum entanglement. (Credit: J-Wiki at Wikipedia)

To put it more simply, if you measured a system of two coins and found it to have one head and one tail and then separated them by a great distance. Once separated if you measure one to be a head, then the other must be a tail no matter how far apart they now are. (Mind you the trick is to separate the two particles or coins without breaking the entanglement.) This effect has been both demonstrated and calculated using only the real parts of the wave function ψ.

Einstein considered quantum entanglement to be “spooky action at a distance” but that doesn’t mean it’s not real. (Credit: Quantum Mind)

The new thought experiment starts by making things more complicated. Let’s say I have two entangled particles and send one to a friend in California named Perry and the other to a friend in Florida named Nancy. Another physicist in Illinois also has a pair of entangled particles and sends one to Nancy in Florida and the other to a friend in Massachusetts named Bill. Notice how the second set of particles doesn’t come from me.

Now the question. Are the two particles received by Perry and Bill entangled, keeping in mind that Nancy got one from each of us? Well the only way to get the answer that everyone expects to be correct, remember this experiment hasn’t been performed yet, is by assuming that the imaginary part of the wave function of the entire system has a physical reality.

Euler’s equation, which contains only the five principal constants of mathematics, is often called the most beautiful equation. (Credit: Live Science)

At the moment the paper, which includes physicists Marc-Olivier Renou of the Institute of Photonic Sciences in Spain and Nicolas Gisin at the University of Geneva, is undergoing peer review so these results are preliminary. Also, if the groups thought experiment does survive scrutiny you can bet someone is going to try to perform the experiment for real.

We all feel this way sometimes when we have to work with imaginary numbers! (Credit: Medium)

Imaginary numbers have befuddled both mathematicians and scientists for going on 500 years now and will undoubtedly continue to do so for even longer. The whole thing seems so simple, yet so weird, and trust me if you don’t pay attention you can screw them up so easily. I guess maybe it’s just a little more evidence of how important our imagination is in understanding reality.

Book Review: ‘Prelude to Extinction’ by Andreas Karpf.

Attention all ‘Star Trek’ fans, here’s a book I think you’ll enjoy. Really, ‘Prelude to Extinction’ the first novel by experimental physicist Andreas Karpf reads very much like a good episode of that sci-fi classic. Captain Jack Harrison of the Earth vessel Magellan is absolutely cut from the same cloth as James T. Kirk and his first officer George Palmer and science officer Don Martinez will often remind you of Mister Spock and ‘Bones’ McCoy.

Cover of ‘Prelude to Extinction’ by Andreas Karpf. (Credit: Amazon)

And like an episode of ‘Star Trek’ the story line in ‘Prelude to Extinction’ is as much action-adventure as it is sci-fi. Even so Author Karpf manages to give the star ship Magellan a good hard feel, all the technology is based on extrapolation from present knowledge so you can actually imagine Magellan as a real ship. This is very much like the feel sci-fi fans got when they first traveled aboard the U.S.S. Enterprise back in 1967, deliberately so I’m certain.

Like the starship Enterprise in ‘Star Trek’ the starship Magellan has the feel of a ship that could actually exist. (Credit: Popular Mechanics)

Now don’t get me wrong, ‘Prelude to Extinction’ is not fan fiction. The novel is set in a completely different imaginary reality with completely different characters. It just all feels familiar, Mister Karpf’s style is right out of the style of the original ‘Star Trek’ series and it shows.

When he’s not writing novels Author Andreas Karpf is a Research Project Manager at NYU Center for Urban Science & Progress. (Credit: Twitter)

The story takes place in the year 2124, just a hundred years from now as the first Earth starship Magellan is entering the Epsilon Eridani star system at a distance of a little over 10 light years from our Solar System. Now astronomers know that E Eridani is a bit smaller and cooler than the Sun, and that it has several planets orbiting it. The fourth of those planets, E Eridani D orbits within the star’s ‘habitable zone’ where liquid water can exist and therefore is a potential home for life.

Epsilon Eridani is one of the closest stars to our Sun and the closest with a large solar system, one planet of which could have liquid water on its surface. (Credit: stars.astro.illinois.edu)

In the novel recent observations by telescopes on the Moon have found conflicting evidence for the existence of intelligent life on D. This is the mission of the Magellan, to discover if there is a civilization on E Eridani D.

The Epsilon Eridani star system compared to our own. E Eridani is the closest star that appears to have a planet within the so-called ‘habitable zone’. (Credit: Sci-News.com)

What the crew of the Magellan find is the ruins of a single city, destroyed apparently by violence along with a strange alien artifact in orbit around the planet. It isn’t long thereafter that the Earthlings are caught in the middle of an interstellar war between two much more advanced alien species, a war that could quickly engulf the Earth and all of humanity.

I do have a few problems with ‘Prelude to Extinction’, for one thing there is a dry stretch about one quarter into the book between where the crew are beginning to realize what’s going on and their first meeting with aliens. Then there are the aliens themselves, one species is just too goody-goody while the other are too bloodthirsty, both just a bit too cartoonish. Finally in the battle sequences Captain Harrison comes off as a bit too heroic, so much so he makes Captain Kirk seem like a pansy. 

There were times in ‘Star Trek’ when Captain Kirk was just tooooo heroic. Captain Harrison in ‘Prelude to Extinction’ is often that way as well! (Credit: Neatorama)

‘Prelude to Extinction’ isn’t a profound work of SF that examines humanity’s place in the Universe like ‘Childhood’s End’ or ‘The Foundation Trilogy’. Neither does it try to illustrate how we humans are going to have to learn to live on the new worlds we explore like ‘The Martian.’ No, ‘Prelude to Extinction’ doesn’t pretend to be anything more than an action adventure Sci-Fi novel and in that respect it succeeds. If you’re in the mood for an enjoyable ‘Star Trek style’ story you should check out ‘Prelude to Extinction’ by Andreas Karpf.

Space News for April 2021.

Like the Wright brothers’ first flight, which only went 36 meters, the April 19th flight of the Ingenuity helicopter may not have gone far, but it was the first powered flight by a human built aircraft on another planet. There’s also a lot of other news concerning both manned and robotic spaceflight but I’ll begin with Ingenuity.

The Ingenuity helicopter resting on the Martian surface prior to its first flight. Notice the tracks of the Perseverance rover in front of the ‘copter. This image was taken by Perseverance. (Credit: CNN)

NASA’s newest rover to Mars Perseverance carried the tiny, 1.8 kg, Ingenuity helicopter with it to the red planet as it made its landing back on the 18th of February. Then a little more than a month later on March 28th the rover gently placed the small helicopter on the Martian surface in preparation for its first flight. After taking several days to check out Ingenuity’s system it was decided to carry out one last full spin test of the helicopter’s rotors on April 9th leading to a scheduled first flight on April 11th.

Perseverance deploying the Ingenuity helicopter. (Credit: CNET)

As with any new technology there are always teething problems and during the April 9th test the Ingenuity rotors failed to reach their full spin speed of 2500 RPM. Taking about a week to investigate the problem and transmit a new software package to the helicopter the engineers at NASA’s Jet Propulsion Labouratory (JPL) carried out a more successful test on April 17th. With that final test completed the first flight of Ingenuity was scheduled for the early morning hours of April 19th. To watch a YouTube video of that first flight click on the link provided https://www.youtube.com/watch?v=QfHfQamhimE

The flight plan was deliberately simple; the small helicopter would rise about 3m into the air and hover in place for a few seconds. While hovering Ingenuity would turn 90º, hover for a little while more before descending and landing, as close to it’s takeoff location as possible.

It all went perfectly and the proof of just how successful the test went was provided by a video taken by the Perseverance rover parked just 20m away. With this first, historic flight completed the engineers at JPL went on to conduct two other flights with the longest lasting 80 seconds aloft while traveling 100 meters at a maximum speed of 7.2kph. With three flights completed, two additional flights for the little helicopter remain to be carried out in earl May.

A few facts about Ingenuity and its first flight. (Credit: Phys.org)

Ingenuity after all is a technology demonstrator; it was designed to see if flying on Mars, where the atmosphere is only 1% as dense as here on Earth, was even possible. The helicopter’s creators want to learn everything they can about the problems and possibilities of flight there. Nevertheless during those test flights it is hoped that Ingenuity may prove useful to Perseverance as a reconnaissance aircraft looking for interesting rock formations that Perseverance can then examine close up.

And Perseverance may have a new neighbor on the Martian surface before long as the Chinese space agency has announced plans to send the descent module of their Tianwen 1 space probe for a landing sometime in mid-May. The Tianwen 1 probe, which entered orbit around the red planet in February, consists of a combined orbiter and lander modules and the scientists leading the mission have spend the last two months both checking out the spacecraft and determining exactly where they wanted to target their lander. If successful the Tianwen 1 lander would make China only the second nation to successfully place a robotic probe on the Martian surface.

China’s Tianwen-1 space probe is currently orbiting Mars and preparing to detach and land a small rover. (Credit: Yahoo news UK)

Further out in the Solar System NASA’s Osiris-REx space probe will leave orbit around the asteroid Bennu on May 10th and begin its long journey back to Earth. Osiris-REx has been studying the asteroid for 3 years and back on October 20, 2020 and even made contact with Bennu in a Touch and Go sample collecting maneuver. Currently Osiris-REx is conducting one last flyover of Bennu paying particular attention to the area where it carried out the Touch and Go.

Images taken during Osiris-REx’s Touch and Go landing on the asteroid Bennu. (Credit:NewsBeezer)

You see during that maneuver the spacecraft’s sample gathering arm sank a full 48.8 cm into the asteroid’s surface and when Osiris-REx fired its thrusters to pull away a considerable amount to dust and debris erupted in the asteroid’s low gravity. While no harm was done to Osiris-REx the scientists at JPL were curious as to whether the Touch and Go had altered the surface of Bennu.

Before and after images of the surface of Bennu. Osiris-REx made a nice little divot on the surface. (Credit: NASA)

Turned out the encounter had left a nice scar where Osiris-REx landed, a mark that could last for thousands of years in the airless microgravity of Bennu. Just another example of how the human race is now making a mark not only on our own planet but also throughout the Solar System.

There are a few other brief items that I’ll cover quickly. The final two passengers have been selected for the first fully commercial space flight. As I mentioned in my post of the 17th of March of this year billionaire Jared Isaacman has hired Space X to send him and three ‘guests’ into orbit for a 3-5 day long ‘vacation’. Isaacman wants to use the flight to help publicize his favourite charity, Saint Jude’s Children’s Research Hospital and so for his first companion he choose physician’s assistant Hayley Arceneaux who was herself a cancer patient at St. Jude’s when she was a child.

The two remaining seats on what has been christened the ‘Inspiration 4’ mission will now go to Doctor Sian Proctor and Chris Sembroski. Doctor Proctor is a Geoscientist and space communication expert who was awarded her chance to travel into space by winning a contest sponsored by Isaacman’s e-commerce company Shift 4 payments.

The crew of Inspiration 4 mission. Left to right, Jared Isaacman, Hayley Arceneaux, Sian Proctor and Chris Sembroski. (Credit: Daily Express)

Mister Sembroski was chosen from some 72,000 entries to a fundraising contest benefiting St. Jude’s and will serve as a mission specialist for the flight. Currently the mission, which will launch from pad 39A at the Kennedy Space Center, is scheduled to take off no earlier than September 15 of 2021.

Even while Space X is moving forward with its commercialization of human spaceflight Boeing’s Starliner Space Capsule can’t seem to get off the launch pad, quite literally. The final unmanned test flight of Starliner, officially Orbital Flight Test-2 (OFT-2), had been scheduled for this month but because of technical problems with the capsule’s avionics that launch date will have to be delayed at least a month.

The Boeing Starliner capsule being readied for its second OFT-2 flight. Continuing problems have now delayed that flight until at least August! (Credit: CNET)

Problem is that the launch facilities at Kennedy are booked right through mid-summer. The earliest date possible for Starliner’s unmanned flight is August, which will almost certainly push back the earliest manned test flight, officially Crew Test Flight-1 (CTF-1) currently scheduled for September. Just further delays on a program that seems to be going nowhere.

Oh, and speaking of Space X, the Hawthorn California based company launched it’s third manned mission to the ISS. The mission, officially named Crew-2 by NASA, carried two NASA, one European Space Agency and One Japanese Space Agency astronaut into Low Earth Orbit (LOE) on the 23rd of April. Mission commander Shane Kimbrough along with pilot Megan McArthur rode their Falcon 9 rocket with mission specialists Thomas Pesquet and Akihiko Hoshide to relieve the current Crew-1 astronauts and begin a 6-month tour aboard the ISS. The Crew-1 astronauts are scheduled to return to Earth aboard their Space X dragon capsule on the first of May.

In this image made from NASA video, the SpaceX Crew Dragon spacecraft lifts off for the Crew-2 mission carrying NASA astronauts Shane Kimbrough, Megan McArthur, ESA (European Space Agency) astronaut Thomas Pesquet, and Japan Aerospace Exploration Agency (JAXA) astronaut Akihiko Hoshide from Launch Complex 39A, Friday, April 23, 2021, at the Kennedy Space Center in Cape Canaveral, Fla. (NASA via AP)
The Space X crew 2 astronauts, in black jerseys, join the other astronauts aboard the ISS. These 11 crew members represents the most people in space at the same time since the end of NASA’s shuttle program. (Credit: SpaceNews)

With their third manned mission for NASA in less than a year and the coming launch of their first purely civilian mission Space X is generating quite a lot of excitement. Is this the start of a new age in space with commercial and national agencies working together to explore our solar system?

I’ve gotten my Covid vaccinations. I’m all immunized. How ’bout you? When are you planning on getting your shots?

As I’m writing this post the number of Covid-19 vaccines that have been administered is here in the United States is 218,947,643. President Biden’s initial pledge of 100 million shots in his first 100 days in office has been more than doubled and even his updated pledge of 200 million in 100 days is a safe bet to be exceeded by more than 10%.

As President-elect Joe Biden pledged to administer 100 million vaccine shots into American arms in his first 100 days as President. He ended up more than doubling that goal. (Credit: New York Post)

27.1% of all Americans have now been fully immunized while more than 50% have had at least their first shot. Over the last month an average of about 3 million people per day have received a shot and all Americans over the age of 16 have now been declared eligible to receive their shots. (All of these statistics are courtesy of the Center for Disease Control CDC.)

The drive to get people vaccinated is one of the largest peacetime efforts ever undertaking by federal, state and local governments. (Credit: Beaumont Health)

All of that means that we are reaching a critical turning point in our war against a disease that in only a single year has killed more Americans than any of our wars except the civil war. 570,611 Americans have lost their lives to Covid-19 and 31,950,831, nearly one tenth of our country’s population have been sickened according the Johns Hopkins University Covid-19 resource center.

At its peak the covid pandemic death toll was so high that makeshift morgues had to be used to store all of the dead! (Credit: The New York Times)

If we can only continue to vaccinate people at our current pace we will almost certainly reach ‘herd immunity’ within another month or two. Such an achievement will mean that by mid summer the US can begin to really open up. Restaurants, movie theaters, sporting events, all of the industries that have suffered enormously because of the pandemic will be able to resume near normal operations. Our economy, which has recently shown signs that it is ready, even anxious to get back to business will be able to do just that. Simply put we’ll be able to get our lives back.

Contagious diseases need a lot of potential victims in order to spread. When the majority of a population gets vaccinated the disease is unable to take hold and spread. (Credit: Wikipedia)

There is a bit of bad news mixed in with the good. There have been cases identified of people who have received their vaccinations and nevertheless later tested positive for covid. That’s actually to be expected, during testing that efficacy of the Pfizer and Moderna vaccines were measured at 95%, which is really good, but still means that 5% of those vaccinated could still get the disease. Even so to date no one who has come down with covid after being vaccinated has become seriously ill or required hospitalization. In other words the vaccines not only do a great job at preventing covid, they virtually eliminate serious cases of the disease.

Some of the vaccines developed to combat Covid are very efficient but none are perfect. (Credit: Statista)

Of course the worst news are those cases of blood clots that have developed in a few people who have received the Johnson and Johnson vaccine. The latest information is that 15 people, all women to my knowledge, have shown symptoms of serious blood clotting after receiving the J&J vaccine and one death has occurred. That number of cases is out of the over 8 million people who have received the single shot J&J vaccine so obviously the incidence of blood clots is very rare. Nevertheless the situation was serious enough that the Food and Drug Administration ordered a pause in the administration of the J&J vaccine while the incidents were investigated. After eleven days of data collecting and analysis of the data both the FDA and CDC decided that the benefits of the vaccine far outweighed the potential risks and lifted the pause while adding a warning to women under 50 informing them of the risk of blood clots.

There is evidence for both the Johnson and Johnson and Astrazeneca vaccines causing blood clots, but there is a greater risk of blood clots from taking birth control pills and even worse for smoking! (Credit: Hindustan Times)

After all consider the odds. Out of about 330 million people living in the US more than 31 million have now gotten covid, that’s nearly a 10% chance of getting the disease and more than half a million have died, a 0.17% chance. On the other hand your chance of getting a serious blood clot from the J&J vaccine is .000188% far, far less likely than the risk due to covid. In fact right now about 700 Americans are still dying every day because of covid while only 15 people have gotten sick because of the J&J vaccine. And remember no deaths thus far have been linked to the Pfizer and Moderna vaccines.

So it’s difficult to understand why so many people are still hesitant about getting vaccinated. In fact current polling data suggest that approximately 17% of Americans only plan on getting vaccinated if it’s required while a further 8% refuse to get vaccinated under any circumstances. These numbers are so large that they could pose a risk to the effort to achieve herd immunity.

According to polls vaccine hesitancy is falling as more and more people get inoculated. We need everyone to realize the benefit of immunization however! (Credit: Statista)

Now there have always been people whose fear of having substances they don’t understand directly injected into their bodies makes them resolute ‘antivaxxers’. Then you can add those people who devoutly believe that faith in god is the only healthcare system they need. Finally in our nation’s current political climate we have many people whose distrust of authority has led them to proclaim ‘their right as Americans to not get vaccinated’. As if the freedom to ignore the deaths of a half million of their fellow citizens is somehow enshrined in the Constitution.

If only it were that easy. (Credit: Henry Kotula)

Remember, covid is a virus; it is incapable of understanding ‘liberty’ in any sense of the word. It is neither a democrat nor republican, neither a liberal nor conservative. It is just going to try to infect you and maybe kill you, that’s all it knows how to do! Face facts, you can’t fight a virus with an assault rifle, nor is this just a left wing plot to destroy conservative American culture. Covid is a disease that is presently out of control and vaccines are our best weapon against it!

Sensible people know this, and know how to analyse risk versus reward. (Credit: SBS)

I’m not going to try to argue with those who will never listen. All I can do is to relate my own medical history as testimony. My parents had our whole family inoculated against polio as soon as the vaccines became available. When I joined the US Navy I was vaccinated I don’t know how many times. I’ve been vaccinated against tetanus, shingles, etc, etc, and I get a flu shot every year. None, I repeat none of those vaccines, including the Pfizer covid vaccine I just received my second dose of, have ever done me the slightest harm.

My vaccination card for the Pfizer Covid-19 vaccine! I’m now all immunized, I can get back to my life…What ’bout you! (Credit: R. A. Lawler)

In fact since the vaccines against Measles, Mumps and Rubella weren’t developed until after I had all those diseases Mumps left me with permanent deafness in my right ear! What I wouldn’t give to have been able to take the MMR vaccine, which you’ll recall is falsely alleged to cause autism, and still have my hearing! So if you’re thinking about getting vaccinated but are hesitant please think of the risks. Over a half a million Americans have died because of covid and maybe one person has died because of a vaccine. Repeat that simple fact about ten times AND GO GET VACCINATED!!!

Paleontology News for April 2021. What was the earliest kind of animal and crocodile diversity?

Back when I was in high school all living creatures were still being divided into just two kingdoms, animal and vegetable. Biologists were well aware of the problems that oversimplified scheme caused, fungi were obviously not plants and single celled organisms often had characteristics of both animal and vegetable, or sometimes neither. Some new classification system was needed but the biologists took their time creating one in order to make certain that they got it right.

Wasn’t so long ago that two kingdoms of life were considered to be enough but notice how the pictures on the cover of this book do not include either mushrooms or single celled organisms! (Credit: Amazon.com)

What they finally decided on was a five kingdom division that has in fact made understanding the relationships between the groups much easier. Multi-cellular creatures are now split into three kingdoms, animals, vegetables and fungi while single celled organisms with a cell nucleus, like an amoeba, are grouped into the protista and single celled organisms without a nucleus, the simplest life forms like bacteria are called the monera.

Five major kingdoms of life are now the agreed upon classification system. (Credit: Iberdrola)

So one of the questions that this new classification scheme generates is, what was the first animal? What was the first multi-cellular creature that had to eat other creatures for their energy, as opposed to plants that generate their energy through photosynthesis?

Early evolutionary biologists were quite confident that sponges, members of the phylum Porifera were the earliest animals because they were certainly the simplest. In many ways sponges are nothing more than colonies of identical cells working in unison rather than the cells of most animals who differentiate and grow into separate organs. That means that sponges have no digestive system, circulatory system or nervous systems or even anything like muscles. Each cell moves its body in unison with the other cells near it generating a flow of water through the body of the sponge and then each cell captures and absorbs its own food particles from that water flow.

In many ways sponges are like hollow tubes with openings, on the side in the example. The cells sit inside the tubes waving their flagella to make water flow through the tube and feed off of particles of food that they catch from the water. The cells are all the same, no differentiating into separate organs. (Credit: Evolution News)

However, when biologists first used DNA analysis to estimate mutation rates in order to calculate which phylum came first it wasn’t sponges that looked like the oldest animals but rather another kind of creature known as ‘comb jellies’ or technically the Ctenophora. This discovery came as a considerable surprise because comb jellies are in many ways considerably more sophisticated creatures possessing not only a gut and muscles but even a very primitive nervous system.

Comb Jellies, phylum Ctenophora, are considerably more complex creatures having two layers of cells, inside and outside, a primitive gut, cells designed to provide motion and even the beginnings of a nervous system. (Credit: Britannica)

The idea that comb jellies came first, then sort of devolved into the less complicated sponges before re-evolving for later more advanced creatures, like us, was hard for many biologists to accept. As geneticist Anthony Redmond of Trinity College in Dublin Ireland remarked however. “It may seem unlikely that such complex traits could evolve twice, independently but evolution doesn’t always follow a simple path.”

Geneticist Anthony Redmond is a post-doc at Trinity University in Dublin. Nice work if you can get it! (Credit: Twitter)

Still such surprising, even baffling results should be double if not triple checked. With that in mind Doctor Redmond and his colleagues reexamined the mutation rates for the two phyla with newer models that even take into account the rate of change for amino acids in the most common proteins. What they found was that the greater range of diversity of the comb jellies was caused by a burst of evolution early in their history leading to a false impression of greater age. The sponges, on the other hand have been a much more conservative group of animals whose lack of diversity made them look artificially younger.

A great deal of work is currently ongoing to measure the mutation rates of various types of creature. (Credit: ResearchGate)

These latest results clearly show that sponges are the earliest animals, just as biologists had always thought. They also show the danger in simply counting the number of changes, mutations in a DNA sequence and then using that as a measure of age. A group of animals that quickly diversifies in order to fill a large number of ecological niches can have a burst of evolution that imitates age. Just goes to show that while genetic studies can tell us a lot about the relationships between living things we still have a lot to learn about how to interpret the data they provide.

Another group of animals who are often considered to be very conservative like the sponges are the crocodilians. In some respects the 26 modern species of crocodiles, alligators and gharials all bear a considerable resemblance to each other and together seem to have little changed since the days of the dinosaurs. So much so that they are often, unfairly called living fossils.

There may be 26 different species of Crocodile in the world today but let’s be honest they are all very similar animals. (Credit: Pinterest)

In fact however crocodiles were once a much more diverse and rapidly evolving group of animals, with swift running land dwellers, dolphin like swimmers and even herbivores, yes plant eating crocodiles! Modern crocodiles may be restricted to a narrow range of ecological niches but there was a time when crocodiles made up a large and very diverse group of animals.

Based on fossil footprints from South Korea one extinct species of crocodile could run for short distances on two legs! (Credit: BBC)
There were also species of Crocs that were evolving to resemble dolphins and whales. (Credit: GeoScience)

A recent study by paleontologists at the University of Bristol in the UK illustrated the extent of crocodilian diversity. In a paper in the journal Proceedings of the Royal Society B the researchers, including lead author Doctor Tom Stubbs, detailed the findings gained from examining more than 200 skulls and jaws spanning the entire 230 million year long history of the group. Ancient crocodiles it turns out were another example of how spreading out into a number of different lifestyles led to rapid evolution and wide diversity. Proving once again that experimentation leads to success.

As a kid I always wanted to have a pet alligator but I knew that was a bad idea!!! Such animals, poisonous snakes and etc., are not good pets and anyone who keeps one is harming the animal and maybe themselves. (Credit: WVXU)

Unfortunately only a small portion of that ancient diversity managed to survive past the reign of the dinosaurs. So we are left today with only a narrow picture of what a crocodile can be. Of course the dinosaurs themselves were virtually wiped out 65 million years ago when an asteroid or comet struck the Earth leaving only their fossil remains to tell us their story.