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How Giant Isopods Got Supersized – Hakai Magazine

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Survival in the deep sea is inherently challenging: darkness abounds, the temperature is near freezing, and food is hard to come by. And yet, rather than wither in the harsh conditions, many deep-sea animals, from massive spider crabs to giant squid, adapt by growing supersized, dwarfing their shallow-water or terrestrial kin. Why these animals get so big has interested scientists for more than a century. Now, by asking a slightly different question—how do they get so big?—scientists are getting closer to an answer.

A team of researchers recently sequenced the genome of the giant isopod Bathynomus jamesi—a first for a deep-sea crustacean. With round, segmented bodies, giant isopods look like roly-polies—except they can grow as long and as heavy as a chihuahua. The team behind the work, led by Jianbo Yuan, a geneticist at the Chinese Academy of Sciences in Beijing, hopes the details hidden in the animal’s genetic code will help us better understand what’s going on behind the scenes, genetically speaking, with deep-sea gigantism.

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Analyzing Bathynomus jamesi’s genes hints at how this giant isopod developed the key adaptations that allow it to thrive in the deep. Photo by Jianbo Yuan and Xiaojun Zhang

Giant isopods, or bathynomids, are the jumbo cousins of the armored crustaceans found milling around under fallen logs. While the smallest isopod species measures less than half a centimeter, bathynomids can grow 80 times longer. The niches isopods occupy are similarly varied: there are more than 10,000 known species, and they’re found everywhere from the bottom of the ocean to caves to mountaintops. This physiological and ecological diversity makes the isopod family tree the perfect place to hunt for clues about what drives adaptation fathoms below.

Among the most interesting questions, says Yuan, is whether or not today’s deep-sea giants simply stem from hefty ancestors—animals like anomalocarids, large arthropod predators that existed some 50 million years ago—or whether they evolved more recently under the pressures of life in the deep sea. In the case of giant isopods, their genome points to the latter explanation.

Like their bodies, bathynomid genomes are incredibly large. B. jamesi, the researchers found, has a high number of so-called jumping genes, transposable elements that can move from one place in the isopod’s genetic code to another. Jumping genes are linked to high rates of mutation, something the researchers think may make the isopod better equipped to deal with environmental stress.

Having a large number of genes is something B. jamesi shares with other deep-sea invertebrates. That invertebrates—organisms generally considered to be less complex than vertebrates—have evolved some of the most complex, adaptable genetic codes has baffled scientists since genome sequencing began.

Beyond revealing the size of its genome, the scientists’ delving into B. jamesi’s biology and genetics have also suggested possible explanations for a number of key adaptations the animal harnesses to thrive in the deep.

B. jamesi’s stomach, for instance, can expand to take up two-thirds of its body. This ensures that, when it can find food, it can gobble as much as possible. Yuan and the team also found in B. jamesi’s genes changes related to thyroid and insulin function, which likely boost the isopod’s ability to grow and absorb nutrients. In addition, they found a tweak that slows the breakdown of fat. Keeping extra junk in the trunk lets giant isopods go years without eating.

Alexis Weinnig, a deep-sea biologist and geneticist at the Leetown Research Laboratory in West Virginia who was not involved in the study, says she likes that Yuan and his team are trying to better understand deep-sea isopods through their genes. Living in the deep sea, isopods are hard to find and harder to study in the field. “I think getting into the basic genetics is going to be a big player in understanding the underlying reasons for gigantism,” she says.

Weinnig hopes the finding reminds people that beyond their potential to help make sense of a scientific quandary, deep-sea species deserve the limelight.

“We lose track of how incredible it is that these animals live on our planet,” says Weinnig. “They have to be resourceful across the board … with reproduction, with metabolic processing. Everything has to be used so that nothing is going to scrap.”

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NASA to launch sounding rockets into moon's shadow during solar eclipse – Phys.org

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This photo shows the three APEP sounding rockets and the support team after successful assembly. The team lead, Aroh Barjatya, is at the top center, standing next to the guardrails on the second floor. Credit: NASA/Berit Bland

NASA will launch three sounding rockets during the total solar eclipse on April 8, 2024, to study how Earth’s upper atmosphere is affected when sunlight momentarily dims over a portion of the planet.

The Atmospheric Perturbations around Eclipse Path (APEP) sounding rockets will launch from NASA’s Wallops Flight Facility in Virginia to study the disturbances in the created when the moon eclipses the sun. The sounding rockets had been previously launched and successfully recovered from White Sands Test Facility in New Mexico, during the October 2023 .

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They have been refurbished with new instrumentation and will be relaunched in April 2024. The mission is led by Aroh Barjatya, a professor of engineering physics at Embry-Riddle Aeronautical University in Florida, where he directs the Space and Atmospheric Instrumentation Lab.

The sounding rockets will launch at three different times: 45 minutes before, during, and 45 minutes after the peak local eclipse. These intervals are important to collect data on how the sun’s sudden disappearance affects the ionosphere, creating disturbances that have the potential to interfere with our communications.

The ionosphere is a region of Earth’s atmosphere that is between 55 to 310 miles (90 to 500 kilometers) above the ground. “It’s an electrified region that reflects and refracts and also impacts as the signals pass through,” said Barjatya. “Understanding the ionosphere and developing models to help us predict disturbances is crucial to making sure our increasingly communication-dependent world operates smoothly.”

A sounding rocket is able to carry science instruments between 30 and 300 miles above Earth’s surface. These altitudes are typically too high for science balloons and too low for satellites to access safely, making sounding rockets the only platforms that can carry out direct measurements in these regions. Credit: NASA’s Goddard Space Flight Center

The ionosphere forms the boundary between Earth’s lower atmosphere—where we live and breathe—and the vacuum of space. It is made up of a sea of particles that become ionized, or electrically charged, from the sun’s energy or .

When night falls, the ionosphere thins out as previously ionized particles relax and recombine back into neutral particles. However, Earth’s terrestrial weather and space weather can impact these particles, making it a dynamic region and difficult to know what the ionosphere will be like at a given time.

It’s often difficult to study short-term changes in the ionosphere during an eclipse with satellites because they may not be at the right place or time to cross the eclipse path. Since the exact date and times of the are known, NASA can launch targeted sounding rockets to study the effects of the eclipse at the right time and at all altitudes of the ionosphere.

As the eclipse shadow races through the atmosphere, it creates a rapid, localized sunset that triggers large-scale atmospheric waves and small-scale disturbances or perturbations. These perturbations affect different radio communication frequencies. Gathering the data on these perturbations will help scientists validate and improve current models that help predict potential disturbances to our communications, especially high-frequency communication.

This conceptual animation is an example of what observers might expect to see during a total solar eclipse, like the one happening over the United States on April 8, 2024. Credit: NASA’s Scientific Visualization Studio

The APEP rockets are expected to reach a maximum altitude of 260 miles (420 kilometers). Each rocket will measure charged and neutral particle density and surrounding electric and magnetic fields. “Each rocket will eject four secondary instruments the size of a two-liter soda bottle that also measure the same data points, so it’s similar to results from fifteen rockets while only launching three,” explained Barjatya. Embry-Riddle built three secondary instruments on each rocket, and the fourth one was built at Dartmouth College in New Hampshire.

In addition to the rockets, several teams across the U.S. will also be taking measurements of the ionosphere by various means. A team of students from Embry-Riddle will deploy a series of high-altitude balloons. Co-investigators from the Massachusetts Institute of Technology’s Haystack Observatory in Massachusetts and the Air Force Research Laboratory in New Mexico will operate a variety of ground-based radars taking measurements.

Using this data, a team of scientists from Embry-Riddle and Johns Hopkins University Applied Physics Laboratory are refining existing models. Together, these various investigations will help provide the puzzle pieces needed to see the bigger picture of ionospheric dynamics.

The animation depicts the waves created by ionized particles during the 2017 total solar eclipse. Credit: MIT Haystack Observatory/Shun-rong Zhang. Zhang, S.-R., Erickson, P. J., Goncharenko, L. P., Coster, A. J., Rideout, W. & Vierinen, J. (2017). Ionospheric Bow Waves and Perturbations Induced by the 21 August 2017 Solar Eclipse. Geophysical Research Letters, 44(24), 12,067-12,073. https://doi.org/10.1002/2017GL076054

When the APEP- launched during the 2023 annular solar eclipse, scientists saw a sharp reduction in the density of charged particles as the annular eclipse shadow passed over the atmosphere.

“We saw the perturbations capable of affecting radio communications in the second and third rockets, but not during the first rocket that was before peak local eclipse,” said Barjatya. “We are super excited to relaunch them during the total eclipse to see if the perturbations start at the same altitude and if their magnitude and scale remain the same.”

The next total solar eclipse over the contiguous U.S. is not until 2044, so these experiments are a rare opportunity for scientists to collect crucial data.

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Royal Sask. Museum research finds insect changes may have set stage for dinosaurs' extinction – CTV News Regina

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Research by the Royal Saskatchewan Museum (RSM) shows that ecological changes were occurring in insects at least a million years before dinosaur extinction.

Papers published in the scientific journal, Current Biology, describe the first insect fossils found in amber from Saskatchewan and the unearthing of three new ant species from an amber deposit in North Carolina, according to a release from the province.

The amber deposit from in the Big Muddy Badlands of Saskatchewan, which was formed about 67 million years ago, preserved insects that lived in a swampy redwood forest about one million years before the extinction of dinosaurs.

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“Fossils in the amber deposit seem to show that common Cretaceous insects may have been replaced on the landscape by their more modern relatives, particularly in groups such as ants, before the extinction event,” Elyssa Loewen, curatorial assistant, said.

The research team was led by Loewen and Dr. Ryan McKellar, the RSM’s curator of paleontology.

“These new fossil records are closer than anyone has gotten to sampling a diverse set of insects near the extinction event, and they help researchers fill in a 17-million-year gap in the fossil record of insects around that time,” Dr. McKellar said.

The three ant species discovered in North Carolina also belonged to extinct groups that didn’t survive past the Cretaceous period.

“When combined with the work in Saskatchewan, the two recent papers show that there was a dramatic change in ant diversity sometime between 77 and 67 million years ago,” Dr. McKellar said in the release.

“Our analyses of body shapes in the fossils suggests that the turnover was not related to major differences in ecology, but it may have been related to something like the size and complexity of ant colonies. More work is needed to confirm this.”

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Meteors, UFOs or something else? Dawson City, Yukon, residents puzzled by recent sightings in night sky – CBC.ca

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Some residents in Dawson City, Yukon, say they’ve been seeing unusual things in the night sky lately — and it’s not the Northern Lights. 

But some might say it’s equally as fascinating.

Over the past few weeks, some residents have taken to social media to report seeing what they described as a fireball or meteor overhead. And last week, two residents said they both saw something similar.

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Naomi Gladish lives in Henderson Corner, a subdivision approximately 20 kilometres from downtown Dawson City. She told CBC News she saw something while walking her dog Friday morning.

“I looked up and saw a bright star,” Gladish said. “Or what I thought was a star.” 

“Within a fraction of a second, I realized it was actually moving quickly. And then as I watched it, a second later it grew a long tail.”

Dawson City resident Naomi Gladish said she saw something similar to the fireball shown in this image from the American Meteor Society. (American Meteor Society)

Gladish said the unknown object started to change into a pale blue colour, like a gas flame. Then, a few seconds later, it appeared to burn out.

“I could see fire, or coal,” Gladish said. “Like red glowing bits, breaking off of it. And then that was it. I tried watching to see if I could see any dark chunks falling from that spot, or carrying on from that spot, but the sky was dark.”

A minute or two after Gladish saw what she thought was a meteor, she heard a boom in the distance.

“My dog and I both turned our head to that exact direction that I had just seen it,” she said.”I figured it was related.”

Two women walking through snowy mountain terrain.
Naomi Gladish hiking with her sister at Tombstone Park. (Submitted by Naomi Gladish)

Dawson resident Jeff Delisle reported seeing something similar at about the same time. He then took to social media to ask if anyone else had seen it. Two people responded saying they had. 

“It flew right above me,” Delisle wrote.

“Pretty cool looking…. What is it?”

Likely not a meteor, says astronomer

Christa Van Laerhoven, president of the Yukon Astronomical Society, came across Delisle’s post and got in touch. She asked about what he’d seen, such as how long it was in the sky and the colour.

Van Laerhoven told CBC News that based on descriptions from both Delisle and Gladish, she doesn’t believe it could have been a meteor.

She says a meteor would have been moving much faster, and the colouring would have appeared differently. 

“Meteors can be any colour but … as a rule, are a consistent colour. What these people were describing had different colours. So the head looked blue and then the tail was more of an orange,” van Laerhoven said.

“That’s just something that doesn’t happen with meteors.”

a meteor
This zoomed-in still from a dashcam video captured in 2020 by Louise Cooke from Mount Lorne, Yukon, shows what one space science expert said appears to be an unusually-bright meteor travelling across the sky. (Submitted by: Louise Cooke)

Van Laehoven believes there may be another explanation for the recent unusual sightings: space junk, falling to earth.

“Space junk, when it comes in … comes through the atmosphere and starts glowing that can be more irregular, because of the variety of materials that go into a spacecraft.”

Van Laerhoven also suggested it could a very fast plane, or someone playing with rockets.

Gladish, however, doesn’t think anyone in Dawson was playing with rockets on Friday morning.

“Unless they’re talking about someone in China, or like a distant land playing with very high, powerful rockets … then sure,” she said.

“This was not something that someone in Dawson was doing … This came from much, much higher and it was much, much different to anything that would be locally caused.”

Van Laerhoven also dismissed another possibility: alien visitors.

“If aliens were coming to Earth, we would know,” she said.

“Simply because it would take them so much effort to get here that it would be very hard to imagine them getting here and not doing something dramatic enough that we would actually know about it.”

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