Jewel scarab beetles look like gold, why?

This video says about itself:

Jewel Scarab in Costa Rica -Chrysina

4 February 2014

Here is a video of a lovely creature I came across during a rain forest exploration. I love insects and this one really took the cake. It’s body was was a like a mirror that reflected all the colors around it.

From the University of Exeter in England:

Secret of why jewel scarab beetles look like pure gold, explained by physicists

‘All that glitters is not gold,’ finds research program into way jewel beetles reflect light

June 15, 2017

The secrets of why Central American jewel scarab beetles look like they are made from pure gold, has been uncovered by physicists at the University of Exeter.

The ornate beetles, which have a brilliant metallic gold colour, are highly valued by collectors. But until now the reasons behind their golden iridescent hue, have not been fully understood.

University of Exeter physicists specialising in colour and light have done experiments exploring the origin of the scarab beetles’ striking metallic golden appearance, showing that the golden beetles have a unique ‘optical signature’. The structure of the beetle and its armour uniquely manipulates the way the light is reflected so that it looks like pure gold.

Their results are published in the Journal of the Royal Society Interface.

Professor Pete Vukusic, a physicist specialising in light and colour, led the research which involved experiments and advanced modelling. He found that the golden appearance is due to the high reflectiveness of the beetles’ exoskeleton, which also manipulates a property of the light called its polarisation: the orientation of the reflected light wave‘s oscillations.

The scientists mapped the optical signature of the beetle’s Chrysina resplendens‘ colour, and found it was unusually ‘optically-ambidextrous’, meaning that it reflects both left-handed and right-handed circularly-polarised light.

Professor Vukusic said: “The brilliant golden colour and distinctive polarised reflection from the scarab beetle Chrysina resplendens sets it completely apart from the hundreds of thousands of other beautiful and brightly coloured animals and plants across the natural world. Its exoskeleton has a bright, golden appearance that reflects both right-handed and left-handed circularly-polarised light simultaneously. This characteristic of Chrysina resplendens appears to be an exceptional and wonderfully specialised characteristic in currently known animals and plants. It will serve as a valuable platform from which bio-inspired optical technologies can spring.”

The golden jewel beetle is prized by collectors because of its resemblance to the precious metal.

Other scarab beetles, valued by ancient cultures such as the Egyptians for use as amulets which were sometimes wrapped in the bandages of mummies, are a jewel-like green and blue colours. The vast majority of brightly-coloured beetles tend to be green and do not reflect polarised light. These beetles, in comparison to the brilliant golden colour of Chrysina resplendens, lack much more specialised aspects of their exoskeleton’s finely detailed structure.

Dr. Ewan Finlayson, research fellow on the project, said: “We were drawn to the study of this jewel scarab not only by its striking metallic golden appearance, but also by its ability to control a less obvious property of the reflected light: the polarisation. We have learned that there is great subtlety and detail to be found in these optical ‘signatures’ and in the elaborate natural structures that generate them.”

The golden jewel scarab beetle Chrysina resplendens, mainly found in the Americas, has evolved an exoskeleton that contains intricate nano-structures that are responsible for its appearance.

The spacing of the repeating layers of the nano-structures is found to vary over a specific range through the exoskeleton — a key property that causes the simultaneous reflection of a range of visible colours. It is this fact that explains the very bright reflection as well as the golden hue.

The nano-structured exoskeleton is composed of natural materials including chitin and various proteins. In addition to their brilliant reflectiveness, these structures are remarkable in the way they manipulate the way polarised light is reflected.

Their nanostructures produce circularly-polarised light, where the orientation of the light’s oscillations rotate as the light travels. The two possible directions of rotation are referred to as left handed and right handed.

The experiments build on the work of an early American scientist called Michelson who, in 1911, looked at the polarised reflection from many different Chrysina beetles, and on the work of Anthony Neville (then at Bristol University) in 1971, who began looking more closely at Chrysina resplendens.

There are around 100 species of Chrysina jewel scarab, which are found exclusively in the New World, mostly in Mexico and Central America. The species Chrysina resplendens is found in Panama and Costa Rica. Chrysina scarabs typically live in mountain forests. The larvae feed on rotting logs of various tree species, while the adults feed on foliage. The larval form lasts for several months to a year, and pupation takes a month or two. After the adult emerges it lives for about a further three months, although this span probably varies between species.

One explanation for the highly-reflective appearance of the beetle exoskeleton is crypsis: the ability of the animal to blend in to its surroundings.

Dr Martin Stevens, Associate Professor of Sensory and Evolutionary Ecology at the University of Exeter and an expert in animal vision, colour change and camouflage, said: “It is not absolutely clear why these beetles are a bright golden colour, but one option is that it somehow works in camouflage under some light conditions. The shiny golden colour could also change how the beetle is seen as it moves, potentially dazzling a would-be predator. There are many species which are iridescent but jewel beetles are one of the most charismatic and brightly coloured, and their colour might be used in mating. However, it is not clear how other beetles see the gold colour and reflected light. Many small mammals would not be able to distinguish the golden colour from reds, greens, and yellows, but a predatory bird would likely be able to see these colours well.”

Astronomical research news

This video says about itself:

7 June 2017

Albert Einstein reshaped our understanding of the fabric of space. In his general theory of relativity in 1915, he proposed the revolutionary idea that massive objects warp space, due to the effects of gravity. Until that time, Isaac Newton‘s theory of gravity from two centuries earlier held sway: that space was unchanging.

Einstein’s theory was experimentally verified four years later when a team led by British astronomer Sir Arthur Eddington measured how much the sun’s gravity deflected the image of a background star as its light grazed the sun during a solar eclipse.

Astronomers had to wait a century, however, to build telescopes powerful enough to detect this gravitational warping phenomenon caused by a star outside our solar system. The amount of deflection is so small only the sharpness of the Hubble Space Telescope could measure it. Hubble observed the nearby white dwarf star Stein 2051 B as it passed in front of a background star. During the close alignment, the white dwarf’s gravity bent the light from the distant star, making it appear offset by about 2 milliarcseconds from its actual position. This deviation is so small that it is equivalent to observing an ant crawl across the surface of a quarter from 1,500 miles away.

Einstein’s light-bending by single far-off star detected. Famous effect of general relativity provides accurate mass of distant white dwarf. By
Lisa Grossman, 11:15am, June 7, 2017: here.

See also here.

Milky Way’s loner status is upheld. Galaxy’s location in a vast cosmic void could help explain dueling universe expansion rates. By
Lisa Grossman, 5:47pm, June 7, 2017: here.

Adolf Hitler’s nazi professors

Hitler’s Professors

By Clara Weiss in Germany:

Hitler’s Professors: A documentation of war crimes by German academics against the Jewish people

16 January 2017

As German academia shifts to the right, expressed in its support for the revival of German militarism, it is important to recall the role played by high-ranking German academics in the Third Reich.

Max Weinreich’s classic study, Hitler’s Professors, first appeared in 1946, with a new edition published in 1999 by Yale University Press. The book presents a thorough account of the participation of leading German academics in the preparation, ideological cover-up and implementation of the murder of European Jews under the Nazis. Professors at Berlin University—the predecessor of Humboldt University, which has recently become an ideological center for the return of German militarism—played an especially important role in the Third Reich.

Max Weinreich was born in 1894, in what is Latvia today, and studied in Germany during the period of the Weimar Republic. Like many of his contemporaries, he was deeply shocked by the Gleichschaltung [Nazification of the state and society] in 1933. Large sections of the academic world voluntarily threw themselves into the arms of the Nazis and placed themselves at the service of National Socialism. Hundreds of intellectuals and academics of Jewish origin, along with those unwilling to adapt to National Socialism, had to leave Germany.

Weinreich is known primarily for his work as a historian and a linguist of the Yiddish language. He wrote his book in Yiddish immediately after the war, on the basis of thousands of documents and publications collected by the YIVO Institute for Jewish Research in New York. In this way, he was able to thoroughly document the complicity of well-known and influential German academics, coming from many different disciplines, in preparing the elimination of European Jewry. Weinreich’s study shows that an entire layer of intellectuals placed themselves in the service of German imperialism, sharing responsibility for the greatest crimes in human history.

At the beginning of his study, Weinreich states: “This murder of a whole people was not perpetrated solely by a comparatively small gang of the Elite Guard or by the Gestapo, whom we have come to consider as criminals. … the entire ruling class of Germany was committed to the execution of this crime. But the actual murderers, and those who sent them out and applauded them, had accomplices. German scholarship provided the ideas and techniques which led to and justified this unparalleled slaughter.” (p. 6)

Weinreich emphasizes that practically all academic disciplines were involved: “Many fields of learning, different ones at different times according to the shrewdly appraised needs of Nazi policies, were drawn into the work for more than a decade: physical anthropology and biology, every branch of the social sciences and the humanities—until the engineers moved in to build the gas chambers and crematoriums.” (pp. 6-7)

Most of the academics discussed by Weinreich were “people of long and high standing, university professors and academy members, some of them world famous, authors with familiar names and guest lecturers abroad, the kind of people with whom Allied scholars used to meet and fraternize at international congresses.” (p. 7)

From the outset, Weinreich argues that the integration of these academics into the Nazi apparatus was by no means an accident. Many of them had already harbored right-wing nationalist and conservative views during the period of the Weimar Republic. He observes: “German scholarship in the post-Versailles period played exactly the same role in supporting Germany’s drive to world domination as in the days of the Kaiser…” (p. 11)

Weinreich names several of the best-known examples of researchers with right-wing nationalist sympathies and National Socialist party membership credentials:

• The Nobel Prize winner for physics, Philipp Lenard, supported the failed Nazi putsch in 1923 in Munich, and was one of the best-known representatives of the so-called “German physics,” which militantly opposed Jewish natural science researchers and called the theories of relativity and quantum physics “Jewish” theories.

• Johannes Stark, also a Nobel Prize Winner in physics and a representative of “German physics,” became a member of the Nazi Party (NSDAP—National Socialist German Workers’ Party) in 1930 and participated in the research and development of an atomic bomb for the Third Reich.

• The philosopher and sociologist Erich Rothacker was a member of the German People’s Party (DVP) before he became a member of the National Socialists in 1930.

• Karl Alexander von Müller, history professor at the Munich Ludwig Maximilian University from 1928 to 1945, had been a Nazi supporter since the 1920s. He taught several of the most despicable Nazis and right-wing ideologists, including Hermann Göring; Baldur von Schirach, who headed the Hitler Youth; Hitler’s later deputy, Rudolf Hess; and the Nazi historians Walter Frank and Wilhelm Grau.

At Berlin University, there was an especially large number of well-known academics who worked with the National Socialists. These included:

• Eugen Fischer, rector of Berlin University and the most famous pseudo-theoretician of so-called “eugenics,” who was also an advocate of the Nuremburg race laws.

• Viktor Bruns, worked at Berlin University as well, and was one of the best-known international law experts of the Weimar Republic. Bruns represented the Nazi government before the permanent international court in The Hague.

• Theodor Vahlen, a mathematician at Greifswald University, had been a national socialist since the 1920s and is considered one of the founders of the so-called “German Mathematics.” Under the Nazis, he subsequently became president of the Prussian Academy of the Sciences and was yet another employee of Berlin University. He later joined the SS.

One could add to this list Konrad Meyer, Professor for Agricultural Science at Berlin University, who played a central role in drafting the Generalplan Ost [General Plan East] which formed the basis for Germany’s attack on the Soviet Union and for the Nazis’ occupation policies in the East.

Researchers in physical anthropology, biology and law were, according to Weinreich, especially ready to embrace national socialism. Among the legal experts, Carl Schmitt was the most famous. As a legal theoretician, he provided the ideological foundation for legitimizing National Socialist legislation, and took part in numerous Nazi conferences on the “Jewish question.” During the Second World War his works were used to justify the German National Socialists’ claim for world domination.

“Research” on the “Jewish Question”

Weinreich spends several pages explaining in detail how the National Socialists made a conscious effort to connect their anti-Bolshevism with anti-Jewish propaganda and substantiate both with pseudo-research. In this, they were basing their views on those of anti-communist Russian immigrants, who fled to Germany after the October revolution and maintained close connections with right-wing nationalist and anti-Semitic circles.

For instance, Weinreich quotes a secret memorandum written by the Jurist Dr. Eberhard Taubert on February 1934, in which he sketched the outlines of anti-Bolshevik and anti-Jewish propaganda. It declared: “Any anti-Bolshevist propaganda is directly in our favor, especially if conducted along these lines: (1) Bolshevism is the gravest danger menacing the world’s security and culture; (2) we have saved the world from this danger; (3) our defense action against communism had to be directed against Jewry too, because they are allied … (6) we are the pioneers of a real understanding of peoples on the basis of mutual respect of nations … If this propaganda is consistently carried through, one must come to understand the new Germany abroad, particularly the authoritarian regime, the concentration camps, the regulation of the Jewish question …” (pp. 113–14)

Taubert, a member of the Nazi Party from 1931, provided the ideas behind the infamous Nazi propaganda film The Eternal Jew, and occupied a high ranking position in Goebbels’ propaganda ministry. After the war, he became an employee and advisor of the leading Christian Social Union politician, Franz Josef Strauß.

Weinreich also documents the numerous institutes devoted to “research on the Jewish question,” which were founded under the National Socialists and ideologically prepared the Holocaust. In addition to Berlin and Munich, Frankfurt-Main became an important center for the ideological preparation of war and genocide.

Among the most influential institutes, which often competed with one another, were:

• The Reichsinstitut für Geschichte des Neuen Deutschlands, [Reich Institute for the History of the New Germany] headquartered in Berlin. This institute systematically supported and carried out pseudo-historical research to provide a theoretical basis for the Nazis’ antisemitism. Physics Nobel Prize winner Johannes Stark and Rudolf Mentzel, president of the Deutsche Forschungsgemeinschaft (DFG) [German Research Foundation], took part in its work and participated in various conferences that it sponsored. Institute conferences were also attended by such high-ranking Nazi officials as Julius Streicher, publisher of the infamous propaganda paper Der Stürmer, and Hans Frank, later governor general of occupied Poland. The Reich Institute published the widely-known series Forschungen zur Judenfrage [Research on the Jewish Question].

• Alfred Rosenberg’s Institut zur Erforschung der Judenfrage [Institute for Research on the Jewish Question], founded in 1939 shortly before the beginning of the war, with its headquarters in Frankfurt-Main. It quickly developed into a leading Nazi anti-Jewish institute. Its library of anti-Jewish literature comprised several thousand volumes. Despite war-time depravations, the Institute received 160,000 Reichsmark during the war to expand its library. Members of the institute, most notably the “expert on Eastern Europe,” Peter-Heinz Seraphim, played a central role in the development of the Nazis’ political orientation towards the Jews in occupied Europe and in the Soviet Union. At a conference in May 1941, academics such as Seraphim and Walter Grau demanded a “definitive solution to the Jewish question,” even before its detailed planning at the Wannsee Conference in January, 1942.

Alfred Rosenberg’s journal Der Weltkampf [The World Struggle], one of the most important ideological organs of the NSDAP since 1925, published contributions from no fewer than 13 professors and 26 Doctors of Philosophy until its last issue in 1944. Among their number were Dr. Klaus Schickert, who wrote his doctoral dissertation on the “Jewish Question in Hungary,” and Peter-Heinz Seraphim, who took over the editorship of the journal. Recent research has revealed that Seraphim’s work on the Jews in Eastern Europe and their movement into ghettos had a significant influence on Nazi planning during the occupation, in particular on the founding and institutionalization of the infamous ghettos.

The Nazis also opened various anti-Jewish institutes in the occupied territories of Europe. For instance, the Institut d’Études des Questions Juives [Institute for the Study of the Jewish Question] was founded in Paris, France, in May 1941, and was led by Dr. George Montandon. It began semiweekly publication of La Question Juive en France et dans le Monde [The Jewish Question in France and in the World] in 1942. In November 1942, a chair for “Jewish history” at the Sorbonne University in Paris was founded, and handed to the right-wing historian Henri Labroue. Institutes were also established in Lithuania, Hungary, Croatia, Romania and Denmark.

Based on the pseudo-research of academics at these institutes, guidelines were produced for teachers to use in Reich schools, along with literature for Wehrmacht soldiers, aimed at preparing them to carry out massacres on the eastern front.

War preparations and the development of National Socialist occupation policy

The geopolitical strategist Karl Haushofer, who had been friends with the Führer’s later deputy, Rudolf Hess, since the 1920s, and had known Adolf Hitler personally since the mid-1920s, played an especially influential role in planning the war in Europe and against the Soviet Union. Haushofer was president of the German Academy from 1934 to 1937. However, in 1939 he distanced himself from the regime and retired. Nevertheless, his fundamental strategic conception, according to which eastern colonization by the German Reich was necessary in order to conquer colonies overseas, was adopted … alongside the General Plan East.

At the universities, so-called “military science,” which was, in fact, nothing less than “the science of war,” was massively expanded. The Hochschule für Politik [Higher School for Politics] in Berlin—predecessor of today’s Otto Suhr Institute at the Berlin Free University—played an especially important role in the war preparations. In 1937, after the majority of its instructors were forced to emigrate in 1933, the government turned it into a Reich institute. After the war began, it became directly affiliated with Berlin University, where it worked out the Nazis’ war policy as the Schule für Auslandswissenschaft [School for Foreign Studies]. This was led by Franz Alfred Six, Adolf Eichmann’s superior in the Reich Security Main Office and one of the central figures in the organization of the holocaust.

Also active in Berlin was the Society for European Economic Planning and Greater Space Economy. It was founded in January 1941, in order to theoretically prepare and legitimize the Nazis’ occupation policy in Europe. Law professor, Carl Schmitt, mathematician Theodor Vahlen, and Dr. Fritz Rörig, president of the History Department of Berlin University, all participated in its work.

The society was connected with the so-called “Führerring” (a ring featuring a Nazi symbol worn by the closest NS collaborators) through several different Reich ministers. Hermann Backe, among others, belonged to the “Führerring.” Backe was the author of the infamous hunger plan for the Soviet Union, which planned the murder and deportation of approximately 30 million Slavs.

The president of the society, Werner Diatz, wrote in the Institute’s first publication: “The thing to do today is to overcome the mental and physical principles of the last two millennia, to revolutionize the European continent as a Teutonic-German continent and to strengthen and complete it as the bulwark of the new idea of national socialism.” (p.126)

To this day, Weinreich’s study remains a standard work and helps explain the role that German universities played in the greatest crimes in the history of humanity. It is thus remarkable that it has never been translated into German, although it became available in English in 1946 and was reprinted, again in English, in 1999.

Weinreich wrote the book during the Nuremburg trials, in the hope that the evidence he presented would aid in the pursuit of the Nazi academic criminals. However, there was never any reckoning with their Nazi past. Only in a few cases were “Hitler’s Professors” forced to give up or change their positions, and even then only temporarily. A few convinced Nazis, like Walter Frank, committed suicide in 1945. In most cases, however, nothing happened. High ranking Nazi academics like Johannes Stark were allowed to live out their retirements undisturbed. Even more, several of the worst ideological criminals continued their careers after the war in the German Federal Republic.

Peter-Heinz Seraphim, like many employees of Rosenberg’s Institute and the Organization Gehlen, joined the newly-founded Federal Intelligence Service (BND). Until the end of his life, Seraphim authored anti-communist pamphlets under the auspices of the Cold War against the Soviet Union. In 1954, he became leader of the Management and Economics Academy in Bochum, an educational institution for Germany’s economic elite.

As already mentioned, Eberhard Taubert became an important ally of Christian Social Union (CSU) politician Franz-Joseph Strauß and was active at the highest levels of German politics into the 1970s.

After his forced retirement in the late 1940s, Karl Alexander Müller again became a member of the Bavarian Academy of Fine Arts in the 1950s, and received the Bavarian Order of Merit in 1961.

Konrad Meyer became a member of the Regional Studies and Planning Academy, and his work continued to be funded—as it had under National Socialism—by the German Research Association (DFG).

Animals and physics, new book

This video says about itself:

Glamorous Indian Peacock

Discover the mating ritual of the Indian Peafowl!

From Science News:

‘Furry Logic’ showcases how animals exploit physics

Book chronicles use of light, magnetism and other phenomena

By Sid Perkins

8:00am, January 7, 2017

Furry Logic
Matin Durrani and Liz Kalaugher
Bloomsbury, $27

Warning: Furry Logic is not, as the title might suggest, a detailed exploration of mammals’ reasoning skills. Instead, it’s a fun, informative chronicle of how myriad animals take advantage of the laws of physics.

Science writers Matin Durrani and Liz Kalaugher cite a trove of recent (and often surprising) research findings. They draw on their backgrounds — Durrani is a physicist, Kalaugher a materials scientist — to explain how animals exploit sound, light, electricity and magnetism, among other things, in pursuit of food, sex and survival. These creatures don’t consciously use physics the way that humans design and use tools, of course, but they are evolutionary marvels nonetheless.

Peacocks, for example, produce low-frequency sounds while shimmying their tail feathers (SN Online: 04/27/16). The birds use these sounds — and not just the sight of those colorful plumes — to impress females and fend off competing males. At the other end of the sonic spectrum, some bats use stealth echolocation to track down their preferred prey. Moths targeted by these bats have sensors that can pick up these ultrasonic calls, but the bats squeak so softly that a moth can’t hear its stalker until it is less than a half-second’s flight away.

Durrani and Kalaugher let readers know when the science isn’t settled. Researchers aren’t quite sure how peahens pick up males’ infrasonic signals, for example. Scientists also haven’t figured out how the archerfish spits so precisely (SN: 10/4/14, p. 8), knocking prey off low-hanging branches above the water as often as 94 percent of the time. The submerged fish must somehow gauge the angle at which light bends as it enters the water and then accurately compensate for refraction while spewing a stream of water. Amazingly, this feat may be innate rather than learned via trial and error.

Readers need not understand the intricacies of polarized light, Earth’s magnetic field or surface tension to enjoy Furry Logic. Nor is this book an exhaustive account of the characteristics and behavior of every animal that uses such phenomena in interesting ways. There should be plenty of material for a sequel to this fascinating book.

2017 science news predictions

This video series from the USA says about itself:

Looking ahead to 2017 | Science News

20 December 2016

From CRISPR to Cassini, science stories on the horizon in 2017 won’t disappoint. We asked our intrepid beat writers what they’ll be looking forward to covering next year. Read more here.

Filming, Production & Editing
Helen Thompson

Additional Video & Images

Matt Heintze/Caltech/MIT/LIGO Lab
Caltech/MIT/LIGO Lab
ESO/Digital Sky Survey 2

McGovern Institute for Brain Research at MIT
Rita Elena Serda,/Baylor College of Medicine/NCI/NIH
Donald Bliss/NLM
Sriram Subramaniam/NCI/NIH
Betty Partin/CDC


Sarah C. Ogden/Florida State University, Tallahassee

Stephen McNally
Roxanne Makasdjian
UC Berkeley


“Climbing The Mountain” by Podington Bear
CC BY-NC 3.0

Top six science videos of 2016

This Dutch 30 December video shows what journalist Maarten Keulemans thinks are the best science videos of 2016.

Starting with #6, ants building a living bridge to cross water.

#5 bioluminescent marine animals discovered near the Mariana islands in the Pacific.

#4 chimpansees mourning one of them which died.

#3 a physics experiment about pressure.

#2 an electric eel jumping.

# 1 dogs having their brains scanned.

Some significant scientific developments of 2016: here.

2016 scientific discoveries, still unconfirmed

This video from the USA says about itself:

Planet 9 Explained and Explored with Astronomer Konstantin Batygin

27 January 2016

Planet 9 is the biggest astronomical “discovery” of recent memory, and the process of calculating its existence is revealed with astronomer Konstantin Batygin. When speculation of a large body of mass with an usual orbital alignment was detected, astronomers took to computer simulations, mathematical equations and a call to the public to discover the small gassous giant on the fringes of our solar system. Batygin breaks down this hypothesized planet that is estimated to be between 1 to 10 times the mass of the Earth, along with the Kuiper Belt, the discovery of Neptune, and why Dr. Mike Brown deemed Pluto no longer a planet in this episode of Antidote hosted by Michael Parker.


Coined the next “physics rock star” by Forbes, Konstantin Batygin immigrated to the U.S. from Russia at age 13 and currently works as an Assistant Professor of Planetary Sciences at Caltech. Batygin landed on the 2015 Forbes list of 30 scientists under 30 who are changing the world with an unprecedented record of publishing 21 papers as first author. He’s discovered planets in other solar systems and solved a centuries-old puzzle: yes, it turns out eventually the planets in the solar system will careen away from the sun. Batygin also plays in a rock band.

From Science News:

These 2016 stories could be really big — if they’re true

Some scientific findings this year made a big splash but require more evidence

By Cassie Martin

10:00am, December 23, 2016

These findings would have rocked the scientific world, if only the evidence had been more convincing.

New Planet 9 clues

A giant planet lurking at the outskirts of the solar system could explain the odd orbits of far-flung hunks of icy debris (SN: 2/20/16, p. 6). If the planet exists, its average distance from the sun would be between 500 and 600 times Earth’s distance (SN: 7/23/16, p. 7).

Signs of ancient life

Mounds of minerals discovered in Greenland appear to have been deposited by clusters of microbes 3.7 billion years ago. If so, these stromatolites represent the oldest fossilized evidence of life on Earth (SN: 10/1/16, p. 7).

Lucy’s big fall

A controversial study claims that Lucy, the most famous fossil in the study of human evolution, died after falling from high up in a tree (SN: 9/17/16, p. 16). The autopsy supports the hypothesis that Australopithecus afarensis split its time between the ground and the trees.

Nucleus with no charge

Researchers have spotted signs of a “tetraneutron,” an atomic nucleus with four neutrons but no protons (SN: 3/5/16, p. 10). If confirmed, this first-of-its-kind nucleus might be explained by a new, interneutron force.