#science news
Hints of an unexpected new particle could be confirmed within days.
If the observations are confirmed, it will be revolutionary. This could mean nothing less than the fall of the Standard Model of particle physics (SM), which has passed every experimental test thrown at it since it was first put together over four decades ago.
We tend to think of COVID-19 as a lung infection, but there’s evidence that it might also be affecting the hearts of healthy athletes without them even knowing it.
The group of bacteria known as Chlamydiae are infamous for the variety of illnesses they cause; but it turns out, we may have Chlamydiae to thank for life as we know it!
Someday in the not-so-distant future your phone could run on bacteria instead of a battery.
There’s been multiple announcements from companies about their COVID-19 vaccine results. Here’s what we know about Pfizer’s.
(Video published 11/20)
Orcas are the assholes of the sea
When Jorge Cervera Hauser went diving with friends in the Sea of Cortez in Baja, California, he was on a mission: to find orcas. Getting in the water with orcas is incredibly rare, Hauser says, and witnessing what they were about to witness, even rarer.
“I’ve been obsessed with orcas for more than seven years now,” says Hauser, CEO of the travel company Pelagic Fleet, “and I always seem to miss them.”
About an hour into the swim, the team spotted a pod of black-and-white whales. (Related: “Exclusive: Mysterious Orcas Filmed Underwater for the First Time”)
“In total, there were around six orcas spread out in groups of two or three. Every time we would jump into the water they would only do a flyby, quickly checking us out,” Hauser recalls. “But around our tenth jump, something changed.”
The orcas noticed a stingray that had come to the surface, possibly to give birth, Hauser says. Instead of zooming by the divers, the orcas began playing with the stingray: circling it, swatting it, and grabbing it to pull it further into the water. (Related: “First Case of Foster Infanticide Observed”)
Hauser says the ray was immediately stunned by the first slap, and was too weak and disoriented to get away from the whales. This behavior went on for about an hour and a half, until the whales killed the ray.
The divers suspected that after smacking around the ray, the whales would eat their prey. But instead, the orcas let the dead animal sink to the bottom of the ocean.
A vaccine for cat-allergy sufferers is on the way
Cat allergy vaccine in development could be game-changer for pet lovers
The Kea, the world’s only alpine parrot, is well known to tear into and eat the fat around the kidneys of living sheep
The kea is a species of large parrot in the family Nestoridae found in the forested and alpine regions of the South Island of New Zealand. About 48 cm long, it is mostly olive-green with a brilliant orange under its wings and has a large, narrow, curved, grey-brown upper beak.
This species of jellyfish cannot die of old age. It achieves this by aging backward after sexual maturity, going through reverse puberty so it can start the cycle again. This cycle can be repeated indefinitely.
3D Map Shows The Milky’s Perplexing Curves
Astronomers have created a new 3D map of the Milky Way galaxy, and in a new paper published in Nature Astronomy, illustrate that the galaxy as a whole has a warped structure, progressively twisting out into a spiral.
This isn’t exactly the biggest surprise. For decades, astronomers have observed a twisting pattern of hydrogen gas out in the far reaches of the galaxy. But since that gas layer extends so far out, it was never really clear whether individual stellar bodies in the galaxy were exhibiting the same kind of warping, and whether there was a consistent warp throughout the Milky Way.
This new 3D map wasn’t even intended to trace the galaxy’s warp. “Most science is serendipitous,” says Richard de Grijs, an astronomer based at Macquarie University in Sydney, and a coauthor of the new study. It was his former graduate student, lead author Xiaodian Chen, now at the National Astronomical Observatories of Chinese Academy of Sciences, who had previously compiled a large collection of observations of over 50,000 stars in the galaxy, particularly in infrared. Chen decided to use observations of the Cepheids—a class of young, bright, pulsating stars—to attempt to outline the shape of the Milky Way.
The Cepheids are particularly useful for any astronomical investigation requiring you to trace distance through outer space. They show period changes in brightness over time, and measuring the cycles in those brightness can basically tell you the distance between two points down to an incredibly accurate scale. And since dust and gas doesn’t absorb much of the light on longer wavelengths, astronomers use infrared to look at those cycles.
And while the warping of the galaxy isn’t a new revelation, Elena D’Onghia, an astronomer at the University of Wisconsin who was not involved with the study, thinks it’s interesting how the team took advantage of the Cepheids in creating the new galactic map that can characterize the warp at a rather high accuracy.
D'Onghia does note, however, that the origin of the warp still needs a more detailed explanation, especially since the hydrogen gas still seems to twist more rigorously then the stars do. “It could be due to torques exerted by a large satellite galaxy like the Large Magellanic Cloud, or the Sagittarius dwarf galaxy that impacted the Milky Way disk not long ago,” she says. “It could be by torques exerted by the inner disk, as the authors claim. [They] do not really explore the different ways to generate the warp as compared to the data.”
Still, there are some larger astronomical questions the findings ought to help resolve, especially when it comes to dark matter. About 85 percent of the universe is thought to be made of dark matter. We can’t directly observe it, but its presence is implied because it gravitationally affects the movements of other celestial structures whirring around through outer space. “We know we need it to explain the motions of the stars in the Milky Way,” says de Grijs. Understanding the shape of the Milky Way means we can get a better handle on where that dark matter is located in the galaxy.
The findings also ought to help the European Space Agency’s Gaia mission, which is tasked with making observations of approximately one billion astronomical objects (about one percent of the Milky Way galaxy). The new map could give the Gaia project a benchmark with which to compare measurements as they come in.
And let’s not forget that Chen’s catalog of 50,000 is ripe for more thorough analysis to unveil more mysteries of the Milky Way. “There’s a lot more we can do with this and continue to explore what’s in the data,” says de Grijs.
How many people can say they have played rugby with a Beluga whale?
A new project in #Germany is retraining prostitutes to become care workers for elderly people.
The state of North Rhine-Westphalia is using €1m (£0.7m; $1.2m) of local and European Union money to try to get #sex trade workers off the street and into care homes.
Heinz Oberlach, from Germany’s Federal Labour Agency, said that using #prostitutes as care workers is “very logical,” as the nursing home sector is seriously understaffed and has some 6400 vacancies nationwide—despite a national unemployment rate of 12% in Germany. Reasons for the shortage include a recent clampdown on Eastern Europeans working illegally as care workers and the reluctance of Germans to take on the work.
Tiny turtle had 104 PIECES of plastic in its intestines when it washed up on a Florida beach and died.
The devastating discovery was reported by the Gumbo Limbo Nature Center in Boca Raton, according to a Tuesday Facebook post.
‘This turtle, which would fit in the palm of your hand, had eaten 104 pieces of plastic,’ the post says.
Garbage dumped in the ocean can last centuries, according to the National Oceanic and Atmospheric Administration.
A plastic bag can last 10 to 20 years and plastic straws as long as 200 before they degrade, reports the administration.
A six-ring plastic drink holder can linger around for 400 years and plastic water bottles 450.
The Gumbo Limbo Nature Center, a cooperative project of the City of Boca Raton, the Greater Boca Raton Beach and Park District, Florida Atlantic University, and Friends of Gumbo Limbo, monitors over 800 sea turtle nests each year within a five mile span of beaches.
'We rescue, rehabilitate, and release sick and injured sea turtles,’ says the group on its website. 'We release more than 9,000 stranded sea turtle hatchlings each nesting season.’
The group, during what is described as 'washback’ season reported that 'weak, tiny turtles are washing up along the coastline needing our help.’
The one turtle found with the deadly plastic pieces in its belly, wasn’t alone, according to the group.
Mesmerising imagery of Hurricane Dorian from space!
What the Sight of a Black Hole Means to a Black Hole Physicist
The astrophysicist Janna Levin reflects on the newly unveiled, first-ever photograph of a black hole.
“At this historic moment, the world has paused to take in the sight of humanity’s first image of the strangest phenomenon in the known universe, a remarkable legacy of the general theory of relativity: a black hole. I am moved not just by the image; overwhelmingly I am moved by the significance of sharing this experience with strangers around the globe. I am moved by the image of a species looking at an image of a curious empty hole looming in space.
I am at the National Press Club, in Washington, D.C., a hive of excitement. Scientists with the Event Horizon Telescope aspired for years to take the first-ever picture of a supermassive black hole, so when they gathered journalists and scientists together today for a press conference, there wasn’t much doubt as to what we were here to see.
But still, there are surprises.
At the podium is Sheperd Doeleman, the director of the Event Horizon Telescope. He welcomes us, ‘black hole enthusiasts.’ I have the strongest memory of standing at the chalkboard in an otherwise empty classroom at the Massachusetts Institute of Technology with Shep, my funny friend with his funny, unmistakable, burnt-mahogany hair. Covered in chalk dust, we acquired the hard-earned mathematics of Albert Einstein’s theory of relativity.
We knew the words already, the standard lore: All forms of matter and energy bend space and time, and light and matter follow those curves. The words have to be taken on trust. But the mathematics we could acquire. It would belong to us. When Einstein conceived of relativity, he gave us a gift that has been passed from person to person around the world. Relativity, defying its name, is true for all of us.
Maybe my memory of that particular board is so crisp precisely because that moment defines the cusp between before and after acquiring relativity. Now I cannot imagine my own mind without it. Relativity permeates my thoughts so that I think in relativity the way writers think in their natural language. Since that time at MIT, Shep and I have both found our way via relativity to the most remarkable of its predictions, black holes.
Black holes were conceived of as a thought experiment, a fantastical imagining. Imagine matter crushed to a point. Don’t ask how. Just imagine that. While enlisted in the German army during World War I, Karl Schwarzschild discovered this possible solution to Einstein’s newly published theory of relativity, apocryphally between calculating ballistic trajectories from the trenches on the Russian front. Schwarzschild inferred that space-time effectively spills toward the crushed center. Racing at its absolute speed, even light gets dragged down the hole, casting a shadow on the sky. That shadow is the event horizon, the stark demarcation between the outside and anything with the misfortune to have fallen inside.
Einstein thought nature would protect us from the formation of black holes. To the contrary, nature makes them in abundance. When a dying star is heavy enough, gravity overcomes matter’s intrinsic resistance and the star collapses catastrophically. The event horizon is left behind as an archaeological record while the stellar material continues to fall inward to an unknown fate. In our own Milky Way galaxy there could be billions of black holes.
Supermassive black holes, millions or even billions of times the mass of the sun, anchor the centers of nearly all galaxies, though nobody yet knows how they formed or got so heavy. Maybe they formed from dead stars that merged and escalated in size, or maybe they directly collapsed out of more primordial material in a younger universe. However they formed, there are as many supermassive black holes as there are galaxies — hundreds of billions in the observable universe.
We had never seen a black hole before today. No telescope had ever taken a picture of one. We have indirectly inferred the presence of black holes when they’ve cannibalized companion stars, powered energetic jets in twisted magnetic fields, and captured stars in their orbit. We have even heard black holes collide and merge, ringing space-time like mallets on a drum.
We had never taken a direct picture of a black hole before because black holes are tiny, despite their dramatic reputation as weapons of mayhem and destruction (yes, the Nova film I hosted was called ‘Black Hole Apocalypse’). A black hole the mass of the sun would have an event horizon a mere 6 kilometers across. Compare that to the 1.4-million-kilometer breadth of the sun itself. The supermassive black hole at the center of the Milky Way, dubbed Sagittarius A*, is 4 million times the mass of the sun but only about 17 times wider.
Consider the challenge of capturing a portrait of an entirely dark object only 17 times the width of an ordinary star at a distance of 26,000 light-years. Resolving an image of Sagittarius A* is comparable to resolving the image of a piece of fruit on the moon.
To resolve such a minuscule image requires a telescope the size of the entire Earth. Since those days in that chalk-dusted classroom at MIT, my funny, utterly unconventional friend has been determined to capture the image of a supermassive black hole all the same.
During our years in graduate school, Shep’s hair was an allegory for his mind — wild and spirited. I admired the freedom I sensed in the way he thought, always forging unexpected connections, sometimes at the expense of the required lesson. His shocked eyes would warn me that a crazy idea had struck him just at that precise moment, as though he was as surprised as I was by the thought.
The Event Horizon Telescope is a testament to bold ideas, as well as scientific ingenuity and collaboration. Exploiting large radio telescopes around the globe — relying on the newest, most sophisticated observatories and reviving some that were nearly defunct — EHT became a composite telescope the size of the Earth. As the planet spins and orbits, the target black holes rise into the field of view of component telescopes around the planet. To render a precise image, the telescopes need to operate as one, which involves sensitive time corrections so that one global eye looks toward the black hole.
Combining telescopes for better resolution was the basis of Shep’s doctoral thesis in the ’90s. By 2008, he led a small team that imaged structures comparable in size to nearby supermassive black holes. That proof of concept drove the EHT project, whose team was now confident that the required resolution was in reach. In the decade since, EHT had to address challenges the data posed and advance technologically, and Shep is quick to credit the international team for their stamina and for the cleverness of their collective contributions.
Our supermassive black hole, Sagittarius A*, became the obvious target to pursue. Despite the abundance of supermassive black holes in galaxies, all others are too far away to resolve even with a telescope the size of the Earth. There is one exception. Messier 87, or M87, is an enormous elliptical galaxy 55 million light-years away that is known to harbor a staggering supermassive black hole somewhere between 3.5 billion and 7.2 billion times the mass of the sun. At the small end of that range, M87 would be an impossible target for EHT. At the high end, it is possibly suitable. So M87 became a secondary target in the heated pursuit of Sagittarius A*.
A black hole against the dark backdrop of empty space would be truly invisible. Sagittarius A* and M87 are helpfully illuminated by debris caught in hot disks orbiting very near their event horizons. The path of the light from the luminous orbiting material is bent along the curved space so that even light behind a black hole gets redirected our way. The disk appears to surround the black hole, allowing for a bright contrast against which its shadow is visible.
EHT actually sees an area slightly outside the event horizon itself — a region defined by the location closest to the black hole where a beam of light could orbit on a circle, known as the ‘last photon orbit.’ (Were you to float there, you could see light reflected off the back of your head after completing a round trip. Or, if you turned around quickly enough, you might see your own face.) Closer than that, all the light falls in.
We are gathered here, black hole theorists and observers, journalists and friends, in this room together to share an image we could already pretty well imagine and were excited to celebrate. But this was the surprise on hearing the announcement: It’s not Sagittarius A* they saw. It’s not our black hole. It’s M87!
The image is unmistakable — a dark shadow the size of our solar system, enveloped by a bright, beautiful blob.
While the scientific implications will take time to unpack, some of the anthropological impact feels immediate. The light EHT collected from M87 headed our way 55 million years ago. Over those eons, we emerged on Earth along with our myths, differentiated cultures, ideologies, languages and varied beliefs. Looking at M87, I am reminded that scientific discoveries transcend those differences. We are all under the same sky, all of us bound to this pale blue dot, floating in the sparse local territory of our solar system’s celestial bodies, under the warmth of our yellow sun, in a sparse sea of stars, in orbit around a supermassive black hole at the center of our luminous galaxy.
When asked his thoughts at the moment he first saw the image of the black hole in M87, Shep replied, ‘We saw something so true.’ And it’s true for all of us.”
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Astronomers capture first image of a black hole
The Event Horizon Telescope (EHT) – a planet-scale array of eight ground-based radio telescopes forged through international collaboration – was designed to capture images of a black hole. Today, in coordinated press conferences across the globe, EHT researchers reveal that they have succeeded, unveiling the first direct visual evidence of a supermassive black hole and its shadow. This breakthrough was announced in a series of six papers published in a special issue of The Astrophysical Journal Letters. The image reveals the black hole at the center of Messier 87, a massive galaxy in the nearby Virgo galaxy cluster. This black hole resides 55 million light-years from Earth and has a mass 6.5-billion times that of the Sun.
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NASA, ULA Launch Parker Solar Probe on Historic Journey to Touch Sun
Hours before the rise of the very star it will study, NASA’s Parker Solar Probe launched from Florida Sunday to begin its journey to the Sun, where it will undertake a landmark mission. The spacecraft will transmit its first science observations in December, beginning a revolution in our understanding of the star that makes life on Earth possible.
Roughly the size of a small car, the spacecraft lifted off at 3:31 a.m. EDT on a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex-37 at Cape Canaveral Air Force Station. At 5:33 a.m., the mission operations manager reported that the spacecraft was healthy and operating normally.
The mission’s findings will help researchers improve their forecasts of space weather events, which have the potential to damage satellites and harm astronauts on orbit, disrupt radio communications and, at their most severe, overwhelm power grids.
“This mission truly marks humanity’s first visit to a star that will have implications not just here on Earth, but how we better understand our universe,” said Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate. “We’ve accomplished something that decades ago, lived solely in the realm of science fiction.”
During the first week of its journey, the spacecraft will deploy its high-gain antenna and magnetometer boom. It also will perform the first of a two-part deployment of its electric field antennas. Instrument testing will begin in early September and last approximately four weeks, after which Parker Solar Probe can begin science operations.
“Today’s launch was the culmination of six decades of scientific study and millions of hours of effort,” said project manager Andy Driesman, of the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland. “Now, Parker Solar Probe is operating normally and on its way to begin a seven-year mission of extreme science.”
Over the next two months, Parker Solar Probe will fly towards Venus, performing its first Venus gravity assist in early October – a maneuver a bit like a handbrake turn – that whips the spacecraft around the planet, using Venus’s gravity to trim the spacecraft’s orbit tighter around the Sun. This first flyby will place Parker Solar Probe in position in early November to fly as close as 15 million miles from the Sun – within the blazing solar atmosphere, known as the corona – closer than anything made by humanity has ever gone before.
Throughout its seven-year mission, Parker Solar Probe will make six more Venus flybys and 24 total passes by the Sun, journeying steadily closer to the Sun until it makes its closest approach at 3.8 million miles. At this point, the probe will be moving at roughly 430,000 miles per hour, setting the record for the fastest-moving object made by humanity.
Parker Solar Probe will set its sights on the corona to solve long-standing, foundational mysteries of our Sun. What is the secret of the scorching corona, which is more than 300 times hotter than the Sun’s surface, thousands of miles below? What drives the supersonic solar wind – the constant stream of solar material that blows through the entire solar system? And finally, what accelerates solar energetic particles, which can reach speeds up to more than half the speed of light as they rocket away from the Sun?
Scientists have sought these answers for more than 60 years, but the investigation requires sending a probe right through the unrelenting heat of the corona. Today, this is finally possible with cutting-edge thermal engineering advances that can protect the mission on its daring journey.
“Exploring the Sun’s corona with a spacecraft has been one of the hardest challenges for space exploration,” said Nicola Fox, project scientist at APL. “We’re finally going to be able to answer questions about the corona and solar wind raised by Gene Parker in 1958 – using a spacecraft that bears his name – and I can’t wait to find out what discoveries we make. The science will be remarkable.”
Parker Solar Probe carries four instrument suites designed to study magnetic fields, plasma and energetic particles, and capture images of the solar wind. The University of California, Berkeley, U.S. Naval Research Laboratory in Washington, University of Michigan in Ann Arbor, and Princeton University in New Jersey lead these investigations.
Parker Solar Probe is part of NASA’s Living with a Star program to explore aspects of the Sun-Earth system that directly affect life and society. The Living with a Star program is managed by the agency’s Goddard Space Flight Center in Greenbelt, Maryland, for NASA’s Science Mission Directorate in Washington. APL designed and built, and operates the spacecraft.
The mission is named for Eugene Parker, the physicist who first theorized the existence of the solar wind in 1958. It’s the first NASA mission to be named for a living researcher.
A plaque dedicating the mission to Parker was attached to the spacecraft in May. It includes a quote from the renowned physicist – “Let’s see what lies ahead.” It also holds a memory card containing more than 1.1 million names submitted by the public to travel with the spacecraft to the Sun.
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Supergene turns spider into a ‘macho male’
Biologists from the Royal Belgian Institute of Natural Sciences (@rbins)found in a spider species that ‘macho males’ have an extra set of genes that is lacking in feminized males. The study in Nature Ecology & Evolution explains how individuals of the same species can develop a strikingly different morphology. “We saw that throughout evolution genes may become grouped together and form a 'supergene’. As a result, they are neatly inherited in a single bundle”, says evolutionary biologist Frederik Hendrickx. Having that supergene or not makes the difference between looking very masculine or feminine in the males of this species.
In nature, you sometimes find two drastically different 'types’ within the same species and even within the same sex. For example, a primrose species has specimens with elevated anthers and anthers that are deeper in the stem, or damselfly and butterfly species with individuals having different colour patterns. This is also the case in the sheet-weaving spider Oedothorax gibbosus. There are two distinct types of males: 'flat’ and 'hunched’. The flat males look more like females and mature more quickly, allowing them to be the first to fertilize females. The hunched specimens have a complex head structure with glands and sensory hairs that allow them to seduce already fertilized females: they are 'macho males’.
Evolutionary biologist Frederik Hendrickx (RBINS): “The differences between these two types of males are enormous, at least as large as between two very different species, such as a tiger and a lion. When you mix tigers and lions you obtain an intermediate form – ligers or tigons, with both lion and tiger characteristics - because the genes are mixed up like a deck of cards. But in some species, like this spider, you neatly retain the two separate types. 'How this is possible is a largely unresolved mystery within evolutionary biology. The gibbosusspiders are a great opportunity to figure out how this works genetically.’
Supergene
The researchers screened the genome and found that the hunched males have a package of genes that is missing from the flat males. The package consists of genes that you also find elsewhere in the genome. Natural selection caused those copies to lie neatly next to each other so that offspring receive them as a single package. "The genome appears to be surprisingly dynamic,” says Hendrickx. “The genes responsible for the development of these conspicuous male traits are moved or duplicated and end up grouped together, so that they are inherited as a bundle. This is a huge eye-opener.”
The bundle is called a supergene. The extra piece of genome not only explains the difference between the two types, but also why we find no intermediate forms, no half-half versions. Only the genes necessary for the development of hunched males have grouped together in this supergene. The flat males can perfectly live without them. This explains why the population breaks down into two types: either super-masculine or female-like males.
Chain Reaction
When the evolutionary biologists zoomed into the supergene, they found that one of the genes in the supergene is a copy of the doublesex gene. All animals - including us - have that gene. Doublesex is a transcription factor: it switches other genes on or off. It’s a big on-button for typical male characteristics. “If the doublesex gene is turned off in mice, the males develop something resembling ovaries,” says Hendrickx. The development of male characteristics in gibbosusspiders occurs after a chain reaction: the sex chromosomes activate that doublesex gene, which in turn turns on other genes that provide male traits, both genes that are inside and outside the supergene package. Flat males have no supergene and therefore no extra on-button doublesex. They don’t develop those extra male characteristics: no hump, no extra glands and no hair. “In most species, the development of sexual characteristics depends on much more than the sex chromosomes. It’s a cascade of genes that are switched on or off, and one link more or less can make a big difference.”
Toolbox
Still, flat males do differ markedly from females. They possess male sex organs, produce sperm and can reproduce. That is because there are five more doublesex genes in other places of the genome, which tap into basic male characteristics.
“You could think of the supergene as a toolbox: over the course of evolution, more and more genes have ended up in that toolbox. An extra doublesex gene and other genes for distinct male characteristics were added to the box because they provided a clear advantage. The spiders with the supergene develop extra male characteristics. Those that do not inherit the toolbox only develop the basic male characteristics.”
[: 1. ARABEL-image bank/Gilbert Loos; 2. RBINS]
Listen to the smell of insects! Researchers have translated odours emitted by insects to defend themselves against predators into sounds.
‘We sent the volatiles via an algorithm to a synthesizer and then tested the sounds on volunteers,’ says entomologist Jean-Luc Boevé (@rbins). 'People reacted to the sounds just as strongly or weakly as the predators to the smells.’
[Hear for yourself]
Chemical signals play a crucial role in the insect world, including as a defence weapon. Take the larvae of sawflies. They are often attacked by ants . The larvae try to keep them at bay by emitting a cocktail of chemical substances that the ants cannot tolerate. Many insect species have similar defence tactics. But how do you measure the effect of that smell on the predator?
There are tests in which ants can perceive substances separately or in a mixture, and their response is measured. But that can be difficult: you need to find sometimes rare insect species in the field and/or rear them in the lab.
Enter: sonification. If you know from a prey insect the chemical substances and their concentrations, you can convert them into sounds . ‘Take a small molecule, such as acetic acid, that evaporates very quickly,’ says Boevé. ‘We gave it a high tone, larger molecules a lower one. Other characteristics influenced the duration, the timbre and volume.’
Boevé and informatics engineer Rudi Giot measured how far the volunteers were walking away from the speakers. Some subjects described certain sounds as unpleasant and frightening. Some sounds would indeed fit in the soundtrack of a horror movie . Boevé: 'To our surprise, the tests showed that the humans reacted against the sounds as the ants did against the odours.’
Belgian mussels developed stronger shells
Belgian mussels have developed stronger shells over the last hundred years. More calcareous shells protect them better from crabs’ claws and seagulls’ beaks. These predators have increased significantly in number during the last fifty years. ‘Belgian mussels adapt surprisingly well to new environmental conditions’, says biologist Thierry Backeljau (RBINS). ‘They might be more resilient to climate change than we think.’
An international team of biologists analyzed the calcareous structure of mussel shells that were collected along the Belgian coast this last century. You would expect the shells to become thinner because more acidic seawater - due to the increase in CO2 in the atmosphere - breaks down calcareous matter. But the team observed a marked increase in the calcification of mussel shells.
The main causes of the more calcareous mussel shells are changes in predators. The dog whelk (Nucella Lapillus) disappeared at the end of the seventies, after which the number of crabs and seagulls increased during the 1980s and 1990s respectively. This led to a pressure on mussels to develop thicker shells, protecting better against the crabs’ claws and the seagulls’ pecking beaks. According to the scientists, this might mean that our Belgian mussel populations can better cope with future climate changes than previously thought.
A special collection
The researchers evaluated a total of 268 mussels that were collected between 1904 and 2016 on the breakwaters between Nieuwpoort and Ostend. The specimens collected between 1904 and 1987 are part of the collections of the Royal Belgian Institute of Natural sciences (RBINS). This unique collection of one single species is composed of ‘wet’ specimens (shells and body tissue, preserved in ethanol), and ‘dry’ specimens (shells only). They were collected during monitoring programs over the past century. ‘This mussel collection is unique,’ says biologist Thierry Backeljau (RBINS), co-author of the study. ‘It may sound paradoxical, but to have such an extended collection of an animal that is so ubiquitous is rare. Researchers usually focus on exceptional species.’
Dog Whelks and acidification
The dog whelk is an important predator of mussels in the North Sea. Dog whelks make a small hole in the mussel shell, through which they suck the mussel empty. To do this, they must drill through the dark, organic outer layer of the mussel: the periostracum. Mussels with a thicker periostracum are better protected against this type of predator. This created a selective pressure on mussels, favoring a thicker periostracum. The acidification of the North Sea - which breaks down calcareous matter - led to additional pressure in favor of more periostracum, offering better protection to the underlying calcareous layer.
But as of the late 1970s, things changed. The dog whelk population suddenly declined sharply and even died out locally due to the use of tin based paint on ship hulls, particularly tributyltin hydride (TBT). The selection pressure on mussel populations in favor of more periostracum decreased.
Crabs and seagulls
In the meantime, average spring and summer temperatures of North Sea surface waters continued to rise, in line with global ocean trends. The input of minerals and nutrients from the land also increased steadily over the past sixty years due to the discharge of fertilizers and wastewater into rivers (eutrophication). The result: an increase in the amount of algae and thus a greater food supply for all kinds of organisms, including the larvae of decapods such as crabs and lobsters. As a result - helped by overfishing of cod, which feeds on those larvae - the number of crabs and lobsters skyrocketed from the 1980s.
Just like the dog whelk, crabs and lobsters are fond of mussels, which they crush with their claws. Protection by a periostracum makes little difference against this, but a stronger, more calcareous shell does. Moreover, depositing calcium requires less energy than producing a periostracum. Thus, a new selection pressure arose, in favor of more calcareous shells.
This selective pressure was reinforced by the exponential population growth of seagulls in the 1990s, due to the increased number of decapods. The breeding season of seagulls (May and June) coincides with the peak of decapods, which are an important food source for the chicks. But seagulls also eat mussels and increased the selection pressure in favor of a calcareous, solid shell.
Hope for the future?
This study shows that the global effects of climate change, such as ocean acidification, do not simply apply on a local scale. Complex, local changes in ecological conditions can lead to biological outcomes that appear to conflict with predictions on a global scale.
‘The Belgian mussel populations seem able to adapt their shell formation to a wide range of local selection pressures and perturbations’, says Backeljau. ‘This gives hope for the future: mussels may be better armed against climate change than we thought.’ This research also illustrates the importance of natural science collections, such as those of the RBINS, in the study of, and fight against, climate change. ‘Collections and archival specimens help us investigate long-term effects of changes in the environment, which is difficult with experimental studies. It is a powerful research method that, as shown here, can yield surprising results and help us get a clearer picture of historical ecological changes’, concludes Backeljau.
The study was published in Global Change Biology.
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A Belgian-Congolese research team has discovered and documented a community of eastern chimpanzees in three small mountain forests in eastern Congo, near Lake Albert. They counted 283 chimpanzee nests in 18 km2 of forest, and estimate that there are 4,6 chimpanzees per km2. The eastern chimpanzee is endangered. More and more forest is turned into agricultural land. The researchers propose authorities to protect these relict mountain forests in the Albertine Rift and involving local communities from the start.
In East-Congo, in the Province of Ituri, near Lake Albert, lies a mosaic of 20 small montane forests fragments, comprising a total surface of 70 km2. This patchwork of forests is called the RAFALE landscape (Relict Altitude Forests Fragments of the Albert Lake Escarpment). In three selected forest fragments, 18 km2 in total, a Belgian and Congolese research team discovered and documented a surviving community of eastern chimpanzees. The eastern chimpanzee (Pan troglodytes schweinfurthii) is an endangered subspecies.
Touching Discovery
In 2015 biologist Anne Laudisoit (University of Antwerp and now EcoHealth Alliance) was doing research on infectious diseases in the area, when she and local guide Otis Kpanyogo heard chimpanzee cries in a very small patch of forest.
In the two following years she led several multinational expedition teams to observe the chimpanzee population. With camera traps the researchers documented 42 weaned chimpanzees and 10 infants. They walked transects - routes along which observations are made - and counted the chimpanzee nests: 283 in 18 km2. In this way they could estimate the chimpanzee density in those three isolated forests: about 4,6 chimpanzees per km2. That’s more than in comparable forest patches in other regions.
‘Having these unknown and undocumented chimpanzees in front of you, and on camera, was just an incredible discovery, and touched every team member’, says Anne Laudisoit, who – together with photojournalist Caroline Thirion – produced a documentary about the chimpanzee community, entitled: Mbudha, in the chimpanzees footsteps.
Protecting Chimpanzees
This RAFALE chimpanzee community, including the Mbudha community in the three forests investigated, is endangered as more and more forest is turned into agricultural land – by slash-and-burn – to grow cassava, groundnuts, beans, maize and sorghum and feed the densely populated communities in the area.
The authors of this study hope that authorities will recognize the RAFALE landscape as a new Chimpanzee Conservation Unit. They would like to see local communities assisted in the design of a sustainable conservation plan for the benefit of both people and wildlife. ‘These small forests are sacks full of life’, says biologist Erik Verheyen (University of Antwerp and Royal Belgian Institute of Natural Sciences). ‘The protection of this area would also help the conservation of the vulnerable Oustalet’s red colobus monkey and the endangered pangolins as well as 26 other mammal species we recorded in this area.’
The study of the Mbudha chimpanzees and their habitat has only just begun. This Spring 2021, Laudisoit (funded by a National Geographic Grant to pursue the explorations) and a team of biologists are undertaking a new expedition to the area and already observed another 15 chimpanzees. One of the goals is to understand how the Mbudha population is genetically connected to or isolated from others in the region.
The Congolese and Belgian researchers involved in this study published their results in the journal Conservation Science and Practice. The team consisted of biologists from Kisangani University (UNIKIS), Centre de Surveillance de la Biodiversité (CSB), Centre for International Forestry Research (CIFOR), University of Antwerp (UAntwerp), Antwerp Zoo Centre for Research and Conservation (CRC), Royal Belgian Institute of Natural Sciences (RBINS) and EcoHealth Alliance.
(Photo credit: Karen Huntt / Corbis, TIME.com “Babies Vs. Chimps…”)
Environment, not evolution, might underlie some human-ape differences (ScienceDaily, 15 July 2019)
Apes’ abilities have been unfairly measured, throwing into doubt the assumed belief that human infants are superior to adult chimpanzees, according to a new study (published in Animal Cognition) by leaders in the field of ape cognition.
[Researchers] say it should come as no surprise that apes raised in institutions would not perform well compared with humans raised in western families, especially when tested with western cultural practices, for example, gestures such as pointing…
“Most studies, comparing apes with human children, for instance, have been poorly designed, with different relevant experiences given to each species, testing them at different ages in many cases, and then claiming to have found a difference in social cognition between humans and apes, but the species haven’t been treated similarly before or during the tests.
"These studies suffer from the same type of prejudice that once existed in studies of human intelligence, which started from a biased position of assuming northern Europeans were innately more intelligent than southern Europeans. We argue the same type of bias is apparent in cross-species studies…”
The researchers say it’s vital scientists realise that environmental experiences vary among humans (both between children and adults, and between people with different cultural experiences) and among apes (also from young to old, and between apes with different experiences).
"…To truly understand the abilities of each species, research needs to examine specific individual learning histories within specific ecological circumstances for both humans and for apes.
“We urge researchers to stop using fallacious research designs and reasoning in studies of comparative cognition.” (full article)
Story Article:
University of Portsmouth. “Environment, not evolution, might underlie some human-ape differences.” ScienceDaily. ScienceDaily, 15 July 2019. <www.sciencedaily.com/releases/2019/07/190715094847.htm>.
Journal Reference:
David A. Leavens, Kim A. Bard, William D. Hopkins. The mismeasure of ape social cognition. Animal Cognition, 2017; 22 (4): 487 DOI: 10.1007/s10071-017-1119-1
