Login
The world’s first transgenic ants have olfactory sensory neurons that flash green in response to odorants.
Ants navigate their richly aromatic world using an array of odor receptors and chemical signals called pheromones. Whether foraging or defending the nest, mating or tending to their young, ants both send and receive chemical signals throughout their lives. And the ant brain is well equipped to process the abundance of scents: The olfactory processing center in the ant’s brain has 10 times as many subdivisions as those of fruit flies, for example, even though their brains are about the same size.
And yet how the ant olfactory system encodes scent data has remained largely unknown.
Contrary to previous findings, the new study in Cell finds that only a few specific areas of the olfactory system lit up in response to alarm pheromones, danger signals that elicit panic and nest evacuation. The results raise questions about how sensory information is processed in the ant brain—as well as tantalizing possibilities for revealing what hundreds of other odorant receptors are up to.
“Neurogenetic tools have revolutionized the field of fruit fly neuroscience over the past decades, while social insect neuroscience has essentially been stuck,” says Daniel Kronauer, head of the Laboratory of Social Evolution and Behavior at Rockefeller University. “Our technical breakthroughs now finally allow us to apply these powerful tools in ants to study their social behavior.”
In 1958, E. O. Wilson reported that a secretion from the mandibular gland of harvester ants triggered their nestmates to quicken their pace and take up colony defense behaviors. He called this response “alarm behavior.” Since then, scientists have documented that alarm behavior and many other complex social activities in ant colonies are regulated by a vast array of pheromones.
Ants’ olfactory receptors are located on neurons in their antennae, which send their input to brain centers called the antennal lobes. The antennal lobes are comprised of specialized structures called glomeruli that are essential to scent processing. Some ants have more than 500 glomeruli—a bounty thought to be related to their heightened ability to perceive and discriminate between pheromones. Previous work from Kronauer’s lab has shown that ants whose odorant receptors have been knocked out cannot respond to pheromone signals.
In this study, the researchers created their transgenic subjects by injecting the eggs of clonal raider ants—a queenless species composed entirely of blind female workers—with genetic material encoding the synthetic protein GCaMP, which lights up neon green when calcium levels change during cellular activity.
“Our goal was to get GCaMP expressed only in a single cell type—the olfactory sensory neurons,” says lead author Taylor Hart, a researcher in Daniel Kronauer’s lab.
This was important because the antennal lobe is composed of multiple cell types: sensory neurons, projection neurons that carry sensory data to other parts of the brain, and lateral interneurons that link everything together. “Those other cell types can make signal-to-noise ratio poor, because they can be doing other activities, such as computations, processing information, and modulating signals,” Hart says. All of this can obscure what the olfactory neurons are doing.
While successfully breeding a small group of ants with GCaMP expression in the olfactory sensory neurons, the team also developed a sophisticated two-photon calcium imaging technique that allowed them to record neural activity throughout the entire antennal lobes of live ants for the first time.
The researchers decided to focus on alarm pheromones, because they are particularly volatile and elicit strong and robust behavioral responses. They found that adult ants that detected the scents immediately scrambled to gather as many eggs in their mandibles as they could and then made a break for it, fleeing into an adjacent section of the test chamber.
Hart and her team then used their new techniques to monitor GCaMP fluorescence levels in the antennal lobes of 22 transgenic ants as they exposed them to a range of odors, including the alarm pheromones (which smell fruity to the human nose). The flashes clustered in six glomeruli in one region, suggesting that area may act as the brain’s panic button.
“We were expecting that a large portion of the antennal lobe would show some kind of response to these alarm pheromones,” Hart says. “Instead, we saw that the responses were extremely localized. Most of the antennal lobe did not respond at all.”
Hart says the findings reveal details about how the ant brain processes sensory input. Researchers have wondered whether the activity is privatized, with each glomerulus responding only to one or a few specific stimuli, or distributed, with unique combinations of glomeruli activated by a stimulus. A brain with more than 500 glomeruli that operated in a distributed way, with hundreds of sensors firing at once, would need extraordinary computational power when it comes to sensory processing, Hart says.
“Most of the odors we tested activated only a small proportion of the total glomeruli,” she says. “It seems that privatization is the way in the ant antennal lobe.”
Considering that only six glomeruli responded out of 500, Hart wonders, “What do they need all these different glomeruli for? The fruit fly gets by with just 50.”
It will now be easier to find out why ants have a greater need to differentiate odor stimuli than other insects, Kronauer says—and not only because Hart has since bred hundreds of transgenic ants who differ from their wild counterparts only in their ability to signal in fluorescence, providing a robust pool for future research.
“The tools that Taylor developed open up a really big range of questions that were inaccessible to us until now,” he says. These include associating specific glomeruli with the variety of pheromones ants use for things like raiding, recruitment, and distinguishing between nestmates and outsiders. “There are also interesting developmental questions about how the ant olfactory system gets assembled, because it’s so complex. Larvae also have olfactory sensory neurons, so now we can look at their sensory capabilities.”
Source: Rockefeller University
The post Transgenic ants glow in response to alarm pheromones appeared first on Futurity.
When he was eight years old, my dad taught himself to take apart watches and put them back together. He supported his mother by doing watch repairs at that age out of her little jewelry stand, and a few years later by delivering clothes for a Chinese laundry.
As a laundry delivery boy, he earned no salary—he lived off tips. Emanuel Romano, a starving modern painter and customer of the laundry service, could not afford to tip Murray, but in lieu of cash, he offered to teach the boy how to paint. My father accepted the lessons and painted for most of the rest of his life. (Our home in Pittsburgh would one day be filled with Murray’s paintings. All would be lost in the flood that later destroyed his home.)
In his early years, Murray couldn’t read. He was probably autistic and dyslexic, but nobody back then knew from that. And a public school in Queens in the 1930s was certainly not going to have the resources to help a child with those issues. When beating him didn’t improve his skills, the school labeled him “sub-normal” and stuck him in Special Ed. He would likely have remained there and become a janitor, or a grifter like his father (my grandfather). But one remarkable public school teacher spotted Murray’s gifts. “This boy is brilliant,” he said.
That changed everything.
(Everything except my grandfather, from whom my dad got nothing but violence and psychological cruelty. When Murray was one of two kids from his neighborhood to be accepted into Bronx Science—a rigorously academic public high school specializing in engineering, mathematics, and the sciences—his father said simply, “They’ve made a mistake.”)
Murray enlisted in the Navy at 17 to fight the Nazis, but they surrendered before he reached Germany. The navy then shipped him off to Japan, but the atomic bomb got there first.
On returning after the war, he attended CUNY on the G.I. Bill, studying electrical engineering. He eventually took his Masters—not bad for a slum kid from a poor family. He would go on to work in robotics, fluid hydraulics, and even early typesetting computers. He came the director of a Research & Development laboratory in Pittsburgh, and afterwards, spent 25 years working for himself as an author, consultant, and lecturer.
Below is his biography from twenty years ago. At the time, he was still vigorous, still flying all over the world as a consultant and lecturer. If you wish, you may skip down to the bottom, where I tell what became of him.
Maurice Zeldman, President
A world authority in the field of project management, Mr. Zeldman has consulted and led seminars for over 180 client organizations. His in-company and public seminars have been presented around the world. Advanced project managers use his special techniques to create realistic estimates, time frames, and implementations which enable the completion of these development projects on schedule and within budgets.
Before launching his EMZEE Associates consultancy, Mr. Zeldman served with Rockwell International as the Corporate Director of Technical Development for the Industrial & Marine Divisions. Responsible for all of the division’s new product and process development projects, he designed, built, and staffed an Engineering Development Center for the corporation.
Previously Mr. Zeldman served with Perkin Elmer in the development of an Atomic Absorption Spectrometer, and with American Machine & Foundry as Chief Engineer of the Versatran Robot business venture.
He is the author of “Keeping Technical Projects on Target” and “Robotics: What Every Engineer Should Know.” (Book links at Amazon.)
My mother died in 2000 after seven years with Alzheimer’s.
My father remarried the next year.
His second wife divorced him when he came down with dementia at age 91.
He was also experiencing seizures. While he was hospitalized for one of them, his house flooded, and everything he owned was destroyed.
My brother Pete found our father a clean, decent nursing home to live in.
There, his dementia progressed quickly.
The last time he saw me with my daughter, he mistook her for my wife and asked how we two had met.
He accused the nursing home staff of soiling his underwear while he slept.
He often sneaked out of the facility to buy scissors, which he smuggled back into the home. (Scissors were contraband because the home feared that their demented patients would use the blades to harm themselves. He had no practical use for the scissors, but was incensed at being told he could not have them.)
During the first year of the Covid pandemic, he contracted pneumonia.
He died at age 93 while in palliative care. He was alone.
#
The post My father’s story appeared first on Zeldman on Web and Interaction Design.
Imagine setting out to explore a distant barren alien landscape, or somewhere earth bound like the “tortuous” glacial-carved topography of Sarek, Sweden, all accompanied by an electronic score composed by the likes of Carbon Based Lifeforms. Your imagination might very well conjure adventuring accessories similar to the Teenage Engineering’s Field System, a collection of functional bags and accessories equipped for exploration, earthly or otherwise.
The monochromatic collection is characterized most notably but its all-white minimalist theme, one realized in nylon 66 shell fabric complemented by black detailing across closure and zipper lines. The nylon material is both fire retardant and backed with polyurethane leather offering the wearer a 3000mm water repellent rating, affording confidence the contents within remain safe regardless whether you’re climbing up to investigate volcanic activity, plumb the depths of a glacial carved stream… or simply make it back to your car in the rain in this extremely wet winter.
The series is designed to go anywhere, with dry water repellent Japanese mini ripstop nylon accessorized with aluminum alloy hardware, including zips and rings.
Numerous pieces of the Field Series collection, like the Field Medium OP–Z Bag and Field Large OP–1 Bag, are designed specifically to secure Teenage Engineering’s catalog of synths and other musical devices, but are also adaptable for carrying all shapes and sizes of gear.
The Field Backpack includes a field keychain carabiner and even a sitting pad.
Embroidered graphic patches further play up the Interstellar-themed designs.
Beyond bags and carrying cases, the Field Series full range also includes t-shirts and sweatshirts emblazoned with mission/music oriented graphics, water bottles, notebooks, and bottle openers starting from $9 with the entire collection available now at TeenageEngineering.com.
Lego bricks can be used to create complex and fascinating mechanical marvels, as demonstrated in this YouTube video that showcases the assembly of 20 different kinds of linkages and other mechanisms using Lego bricks.
The video features a variety of linkages, including a Schmidt coupling, universal joint, torque limiter, and constant-mesh gearbox. — Read the rest
A few months back, I received two separate PR pitch emails at nearly the exact same time. One was an invitation to a speaking event in Texas hosted by a "free speech" conservative publishing company, featuring Kyle Rittenhouse as a keynote speaker. — Read the rest
Stop us if you’ve heard this one before, but a Russian spacecraft docked with the International Space Station has sprung a leak. On Saturday morning, Russia’s Roscosmos space agency disclosed on Telegram that a Progress cargo ship docked with the ISS had lost cabin pressure. NASA later said the depressurization was due to a coolant leak.
“The reason for the loss of coolant in the Progress 82 spacecraft is being investigated,” NASA announced. “The hatches between Progress 82 and the station are open, and temperatures and pressures aboard the station are all normal. The crew, which was informed of the cooling loop leak, is in no danger and continuing with normal space station operations.”
Per Space.com, Progress 82 arrived at the ISS on October 28th. Before Saturday's announcement, the spacecraft was scheduled to leave the station on February 17th. It’s unclear if Roscosmos will move forward with that timeline as originally planned. Russia’s Progress spacecraft are designed to burn up in the Earth’s atmosphere after they complete their resupply missions, meaning there’s no way for Roscosmos to investigate the leak on the ground. The timing of the discovery comes on the same day that a second Progress spacecraft docked with the ISS, and less than two months after another Russian spacecraft sprung a leak at the space station.
In December, Russia’s Soyuz MS-22 spacecraft began leaking coolant just as cosmonauts Dmitri Petelin and Sergey Prokopyev were preparing for a nearly seven-hour spacewalk. Roscosmos later blamed the incident on an apparent meteoroid strike. Unless there’s an emergency at the ISS, Roscosmos has deemed the spacecraft unfit to transport humans. The agency will launch another Soyuz craft later this month to bring Petelin and Prokopyev, as well as NASA astronaut Frank Rubio, back to Earth.
Ars Technica’s Eric Berger points out, the Progress incident raises doubts about whether Soyuz MS-22 was actually hit by a micrometeorite. Russia never released images of the impact, and the country’s space program has a history of recent issues. In 2021, for instance, Roscosmos blamed a software bug on the Nauka misfiring that temporarily moved the ISS out of its usual orientation.
Roscosmos Progress Spacecraft
Image of a Russian Progress supply craft docked with the International Space Station, with the black of space in the background.
FreshRSS 