The Border Between Life & Non Life

“According to two papers published in Cell on January 11, 2018, the making of memories and the processes of learning resemble, of all things, a viral infection. It works like this: The shells that transport information between neurons are assembled by a gene called Arc. Experiments conducted by two research teams revealed that the Arc protein that forms a shell, functions much like a Gag, a gene that transports a virus’s genetic material between cells during an infection. For example, the retrovirus HIV uses a Gag in exactly this manner.

“We already know, thanks to the work of Lynn Margulis, that a number of organelles that power the cells of plants and animals descended from bacteria. This is called the endosymbiotic hypothesis. It’s now widely accepted as a fact of life. Margulis, who passed away in the winter of 2011, also believed that spiral bacteria evolved into the cilia and flagella that animal cells, such as sperm, use for mobility. (She went as far to suggest that the processes of animal thought or cognition were connected with cilia.) The spiral theory is still controversial. But now that scientists have basically concluded that the processes of memory and learning are closely related to innovations independently developed by viruses and adopted by animals deep in time (“Arc works in a similar fashion right across the tree of life, from flies to humans”), it seems foolish to not seriously re-envision animal and plant biology along Margulian lines.


“There is more to think about. Most scientists consider viruses to be non-living. In fact, popular science writer Ed Yong recently made a statement in his piece, “The Viruses That Eavesdrop on Their Hosts,” that concerned a new discovery made by another brilliant scientist, Bonnie Bassler, and her student, Justin Silpe (that viruses can listen to the language bacteria uses for what’s called quorum sensing): “Viruses are not even technically alive! They’re entirely different entities from bacteria, yet they are intercepting and interpreting the same molecular messages. It’s like a rock eavesdropping on a bird.”

“If we can compare a rock to a virus—which appears to come alive when infecting a cell, and appears to be dead when doing nothing—then we must begin to suspect that there’s something life-like in non-biological things like clouds and hills. Are viruses really the border between life and non-life? Is there a border? A break? The 20th century Russian biochemist, Alexander Oparin, maintained there was a continuum from the inorganic to the organic. This is clearly the case from the stand point of the chemical elements. There is nothing in life that cannot be found in non-living things. We have known this since the 19th century, which experienced the demise of vitalism. But life appears to be not like a rock. And a virus appears to be more like life than a rock. Also life is weird. Viruses are weird. A rock is not. Lastly, it seems that animals and trees are wholly Margulisian—meaning, they are chimerical, or monsters that emerged from and are not separate from the ambiance of microganisms…”

Text: Charles Mudede, By Far the Strangest Scientific Discovery of 2018: Your Memories Are a Viral Infection,

Image: Rene Magritte, A Sense of Reality. 1963.

Troxler Effect

“This is called the Troxler effect, after the man who discovered it: Ignaz Paul Vital Troxler, in 1804.

“What happens here is that your visual system constantly adapts to all the external stimuli. This is why after spending a few moments in the dark, you start to see a little better. This capability allows you to be in different lighting conditions, while still maintaining a pretty accurate estimate of the lightness and colour of objects.

“So if you fixate on a certain point, after approximately 20 seconds, stimuli which fit in your peripheral vision will fade away and disappear. The effect is most powerful for some colours and patterns, and is more powerful the farther the object is from your center of fixation…”


Text & Pic: Stare at this picture. It will disappear. ZMEScience.

Signs of Life

“If alien astronomers are out there searching for signs of life on Earth, they might just find it in the telltale pattern of light reflected by our plants, from redwood forests to desert cacti to grass-covered plains. That reflected fingerprint has been visible since vegetation first began carpeting our rocky terrestrial landscape about half a billion years ago. And as Earth aged and evolution marched onward, the reflected signal strengthened.

“Now, two astronomers are suggesting that plants could leave similar fingerprint-like patterns on distant exoplanets, and perhaps the first signs of life beyond our solar system could come from light reflected by forests covering an alien moon like Endor or cacti living in Tatooine’s deserts.


“We’re trying to figure out—with all the planets we’re finding—what are the signatures that could indicate habitability?” says Cornell University’s Lisa Kaltenegger, who recently described Earth’s leafy signature in a study published in the journal Astrobiology.

“We really want to identify the handful, or two or three, that give us the best chance to pick up signs of life.”

“While this isn’t the first time scientists have suggested looking for life in a far-off planet’s light, Kaltenegger’s team adds a twist: Such reflections can also offer a good estimate for an alien planet’s evolutionary advancement, based on our knowledge of how things work on Earth.

“This idea that you could find vegetation on another planet has been around. But nobody ever used Earth’s own geological history as an archive,” Kaltenegger says. “We don’t have a second planet with habitability, but we do have our Earth through time, and it would be really smart to study it.”

“Several decades ago, the Galileo spacecraft, which was headed for Jupiter, swiveled to stare at Earth’s reflected light. It spied the signs of biology at work in the presence of atmospheric gases such as ozone and methane. More recently, astronomers have teased apart Earthshine, or the bit of Earth-light that sometimes dimly illuminates the darker part of a crescent moon’s face. They found life’s fingerprints there, too.

“Now, scientists searching for life beyond Earth are debating how biology might leave molecular marks in alien atmospheres, either by producing particular compounds or by shifting the mix of gases swaddling a planet.”

Text: “Want to Find Alien Life? Look at Older, Hotter Earths”, National Geographic.
Image: L’occhio di Shui (The Eye of Shui) by Shui Mao.

The Local Standard of Rest

“Whereas all the planets, asteroids and meteors that originate within the solar system more or less circle what is called the Ecliptic plane, that of our sun, since they were formed from the same disc of gas and dust that rotated around itself, Oumuamua entered the solar system north of the plane, in an extreme hyperbolic orbit and at a speed of 26.3 kilometers per second faster relative to the motion of the sun.

“A reconstruction of its trajectory shows that Oumuamua traversed the ecliptic plane on September 6, 2017, when the sun’s gravity accelerated the object to a velocity of 87.8 kilometers per second. On September 9, the object passed closer to the sun than the orbit of Mercury. And on October 14, five days before it was discovered in Hawaii, the object passed 24.18 million kilometers away from Earth, or 62 times the distance from here to the moon.


“I wrote above that Oumuamua originated at Vega, but that’s not completely accurate: The universe is a vast place, and even at Oumuamua’s velocity – a velocity that no human spaceship has achieved – a voyage from Vega to the solar system would take 600,000 years. But in the meantime, Vega is orbiting the center of the Milky Way, like the sun and all the other stars, and it wasn’t in that region of the heavens 600,000 years ago.

“If you average the velocities of all the stars in the region, you get a system that’s called the ‘local standard of rest.’ Oumuamua was at rest relative to that system. It didn’t come to us. It waited in place, like a buoy on the surface of the ocean, until the ‘ship’ of the solar system ran into it. To make things clear, only one of 500 stars in the system is as much at rest as Oumuamua. The probability of that is very low. After all, if it were a stone that was simply hurled from a different solar system, we would expect it to have the velocity of its star system, not the average velocity of all the thousands of stars in the vicinity.”

Text: “If True, This Could Be One of the Greatest Discoveries in Human History”, Haaretz.

Image: Augsburger Wunderzeichenbuch, Comet mit einem grosen Schwantz, 1401

“The planet’s fate is already sealed…”

“Last month, deep in a 500-page environmental impact statement, the Trump administration made a startling assumption: On its current course, the planet will warm a disastrous seven degrees by the end of this century.

“A rise of seven degrees Fahrenheit, or about four degrees Celsius, compared with preindustrial levels would be catastrophic, according to scientists. Many coral reefs would dissolve in increasingly acidic oceans. Parts of Manhattan and Miami would be underwater without costly coastal defenses. Extreme heat waves would routinely smother large parts of the globe.

“But the administration did not offer this dire forecast, premised on the idea that the world will fail to cut its greenhouse gas emissions, as part of an argument to combat climate change. Just the opposite:

The analysis assumes the planet’s fate is already sealed.

“The draft statement, issued by the National Highway Traffic Safety Administration (NHTSA), was written to justify President Trump’s decision to freeze federal fuel-efficiency standards for cars and light trucks built after 2020. While the proposal would increase greenhouse gas emissions, the impact statement says, that policy would add just a very small drop to a very big, hot bucket.


“The amazing thing they’re saying is human activities are going to lead to this rise of carbon dioxide that is disastrous for the environment and society. And then they’re saying they’re not going to do anything about it,” said Michael MacCracken, who served as a senior scientist at the U.S. Global Change Research Program from 1993 to 2002.

“The document projects that global temperature will rise by nearly 3.5 degrees Celsius above the average temperature between 1986 and 2005 regardless of whether Obama-era tailpipe standards take effect or are frozen for six years, as the Trump administration has proposed. The global average temperature rose more than 0.5 degrees Celsius between 1880, the start of industrialization, and 1986, so the analysis assumes a roughly four degree Celsius or seven degree Fahrenheit increase from preindustrial levels.

“The world would have to make deep cuts in carbon emissions to avoid this drastic warming, the analysis states. And that “would require substantial increases in technology innovation and adoption compared to today’s levels and would require the economy and the vehicle fleet to move away from the use of fossil fuels, which is not currently technologically feasible or economically feasible.”

“The White House did not respond to requests for comment.”

Text: Trump administration sees a 7-degree rise in global temperatures by 2100, Washington Post.

Pic: Surface of Venus.