When faced with rushing floodwaters, fire ants are known to build two types of structures. A quickly formed raft lets the insects float to safety. And once they find a branch or tree to hold on to, the ants might form a tower up to 30 ants high, with eggs, brood and queen tucked safely inside. Neither structure requires a set of plans or a foreman ant leading the construction, though. Instead, both structures form by three simple rules:

If you have an ant or ants on top of you, don’t move.
If you’re standing on top of ants, keep moving a short distance in any direction.
If you find a space next to ants that aren’t moving, occupy that space and link up.
“When in water, these rules dictate [fire ants] to build rafts, and the same rules dictate them to build towers when they are around a stem [or] branch,” notes Sulisay Phonekeo of the Georgia Institute of Technology in Atlanta. He led the new study, published July 12 in Royal Society Open Science.

To study the fire ants’ construction capabilities, Phonekeo and his Georgia Tech colleagues collected ants from roadsides near Atlanta. While covered in protective gear, the researchers dug up ant mounds and placed them in buckets lined with talc powder so the insects couldn’t climb out. Being quick was a necessity because “once you start digging, they’ll … go on attack mode,” Phonekeo says. The researchers then slowly flooded the bucket until the ants floated out of the dirt and formed a raft that could be easily scooped out.

In the lab, the researchers placed ants in a dish with a central support, then filmed the insects as they formed a tower. The support had to be covered with Teflon, which the ants could grab onto but not climb without help. Over about 25 minutes, the ants would form a tower stretching up to 30 mm high. (The ants themselves are only 2 to 6 mm long.)
The towers looked like the Eiffel Tower or the end of a trombone, with a wide base and narrow top. And the towers weren’t static, like rafts of ants are. Instead, videos of the ant towers showed that the towers were constantly sinking and being rebuilt.

Peering into the transparent Petri dish from below revealed that the ants build tunnels in the base of a tower, which they use to exit the base before climbing back up the outside.

“The ants clear a path through the ants underneath much like clearing soil,” Phonekeo says. Ants may be using the tunnels to remove debris from inside the towers. And the constant sinking and rebuilding may give the ants a chance to rest without the weight of any compatriots on their backs, he says.

To find out what was happening inside the tower, the researchers fed half their ants a liquid laced with radioactive iodide and then filmed the insects using a camera that captured X-rays. In the film, radioactive ants appeared as dark dots, and the researchers could see that some of those dots didn’t move, but others did.

The team then turned to the three rules that fire ants follow when building a raft and realized that they also applied to towers. But there was also a fourth rule: A tower’s stability depends on the ants that have attached themselves to the rod. The top row of ants on the rod aren’t stable unless they form a complete ring. So to get a taller tower, there needs to be a full ring of ants gripping to the rod and each other.

That such simple rules could form two completely different structures is inspiring to Phonekeo. “It makes me wonder about the possibilities of living structures that these ants can build if we can design the right environment for them.”

After five years on Mars, the Curiosity rover is an old pro at doing science on the Red Planet. Since sticking its landing on August 5, 2012, NASA’s Little Robot That Could has learned a lot about its environs.

Its charge was simple: Look for signs that Gale crater, a huge impact basin with a mountain at its center, might once have been habitable (for microbes, not Matt Damon). Turning over rocks across the crater, the rover has compiled evidence of ancient water — a lake fed by rivers once occupied the crater itself — and organic compounds and other chemicals essential for life.
NASA has extended the mission through October 2018. And there’s still plenty of interesting chemistry and geology to be done. As the robot continues to climb Mount Sharp at the center of the crater, Curiosity will explore three new rock layers: one dominated by the iron mineral hematite, one dominated by clay and one with lots of sulfate salts.

So, here are four Martian mysteries that Curiosity could solve (or at least dig up some dirt on).

Does Mars harbor remnants of ancient life?
Curiosity’s Mars Hand Lens Imager can take microscopic images, but preserved cells or microfossils would still have to be pretty big for the camera to see them. What the rover can do is detect the building blocks for those cells with its portable chemistry lab, Sample Analysis at Mars. The lab has already picked up chlorobenzene, a small organic molecule with a carbon ring, in ancient mud rock. Chains of such molecules go into making things like cell walls and other structures.
“We’ve only found simple organic molecules so far,” says Ashwin Vasavada, a planetary scientist at NASA’s Jet Propulsion Laboratory who leads Curiosity’s science team. Detective work in chemistry labs here on Earth could shed light on whether bigger organic molecules on Mars’ surface might degrade into smaller ones like chlorobenzene.

Curiosity could still turn up intact, heavier-duty carbon chains. The rover carries two sets of cups to do chemistry experiments, one dry and one wet. The latter contains chemical agents designed to draw out hard-to-find organic compounds. None of the wet chemistry cups have yet been used. A problem with Curiosity’s drill in December 2016 has held up the search for organics, but possible solutions are in the works.
How did Mars go from warm and wet to cold and dry?
That’s one of the million-dollar questions about the Red Planet. Curiosity has piled on evidence that Mars was once a much more hospitable place. Around 3.5 billion years ago, things changed.

The going theory is that particles from the sun stripped away much of Mars’ atmosphere (and continues to do so) when the planet lost most of its protective magnetic field. “That caused the climate to change from one that could support water at the surface to the dry planet it is today,” Vasavada explains. Curiosity found a higher ratio of heavy elements in the current atmosphere, adding credence to this argument — presumably the lighter elements were the first to go.

There’s also a chance that as the rover hikes up Mount Sharp it could capture regional evidence of the wet-to-dry transition. So far, Curiosity has investigated rocks from the tail end of the wet period. The new geologic layers it will encounter are younger.

“Hopefully we’ll be able to get some insight by looking at these rocks into some of the global changes happening that maybe no longer permitted a lake to be present on the surface,” says Abigail Fraeman, a research scientist at NASA’s Jet Propulsion Lab.
Does Mars really have flowing water today?
Some mineralized salts absorb water and release it as liquid when they break down at certain temperatures. The Curiosity team looked for the bursts of water that might result from such a process in Gale crater and came up empty.

But in 2015, the Mars Reconnaissance Orbiter snapped images of shifting salt streaks indicative of actively flowing water. The images are the best evidence yet that liquid water might not be a thing of the past.

Mount Sharp has similar dark streaks, and Curiosity periodically takes pictures of them. “It’s something we keep an eye on,” Vasavada says. If the streaks change in a way that might indicate that they’re moving, the rover could corroborate evidence of modern-day water on Mars. But so far, the streaks have stayed stagnant.

Where does the methane in Mars’ atmosphere come from?
On Earth, microbes are big methane producers, but on Mars, methane’s origins are still unclear. Early on Curiosity detected extremely low levels of the gas in Mars’ atmosphere. This baseline appears to subtly fluctuate annually — perhaps driven by temperature or pressure. Curiosity continues to monitor methane levels, and more data and modeling could help pinpoint what’s behind the annual ups and downs.

At the end of 2014, researchers noticed a spike 10 times the baseline level. Scientists suspect that methane sticks around in the air on Mars for only about 300 years. So, the methane spike must be relatively new to the atmosphere. “That doesn’t necessarily mean it’s being actively created,” Vasavada says. “It could be old methane being released from underground.” Minerals interacting with subterranean water sometimes make methane gas.

Mars’ methane could also be the product of planetary dust particles broken down on the surface. And yet another possible explanation is biological activity. “We have zero information to know whether that’s happening on Mars, but we shouldn’t exclude it as an idea,” says Vasavada. So, Martian life is unlikely but can’t be completely ruled out.

If you look at a map of the world, it’s easy to think that the vast oceans would be effective barriers to the movement of land animals. And while an elephant can’t swim across the Pacific, it turns out that plenty of plants and animals — and even people — have unintentionally floated across oceans from one continent to another. Now comes evidence that tiny, sedentary trapdoor spiders made such a journey millions of years ago, taking them from Africa all the way across the Indian Ocean to Australia.

Moggridgea rainbowi spiders from Kangaroo Island, off the south coast of Australia, are known as trapdoor spiders because they build a silk-lined burrow in the ground with a secure-fitting lid, notes Sophie Harrison of the University of Adelaide in Australia. The burrow and trapdoor provides the spiders with shelter and protection as well as a means for capturing prey. And it means that the spiders don’t really need to travel farther than a few meters over the course of a lifetime.

There was evidence, though, that the ancestors of these Australian spiders might have traveled millions of meters to get to Australia — from Africa. That isn’t as odd as it might seem, since Australia used to be connected to other continents long ago in the supercontinent Gondwana. And humans have been known to transport species all over the planet. But there’s a third option, too: The spiders might have floated their way across an ocean.

To figure out which story is most likely true, Harrison and her colleagues looked at the spider’s genes. They turned to six genes that have been well-studied by spider biologists seeking to understand relationships between species. The researchers looked at those genes in seven M. rainbowi specimens from Kangaroo Island, five species of Moggridgea spiders from South Africa and seven species of southwestern Australia spiders from the closely related genus Bertmainius.

Using that data, the researchers built a spider family tree that showed which species were most closely related and how long ago their most recent common ancestor lived. M. rainbowi was most closely related to the African Moggridgea spiders, the analysis revealed. And the species split off some 2 million to 16 million years ago, Harrison and her colleagues report August 2 in PLOS ONE.

The timing of the divergence was long after Gondwana split up. And it was long before either the ancestors of Australia’s aboriginal people or later Europeans showed up on the Australian continent. While it may be improbable that a colony of spiders survived a journey of 10,000 kilometers across the Indian Ocean, that is the most likely explanation for how the trapdoor spiders got to Kangaroo Island, the researchers conclude.

Such an ocean journey would not be unprecedented for spiders in this genus, Harrison and her colleagues note. There are three species of Moggridgea spiders that are known to live on islands off the shore of the African continent. Two live on islands that were once part of the mainland, and they may have diverged at the same time that their islands separated from Africa. But the third, M. nesiota, lives on the Comoros, which are volcanic islands. The spiders must have traveled across 340 kilometers of ocean to get there.
These types of spiders may be well-suited to ocean travel. If a large swatch of land washes into the sea, laden with arachnids, the spiders may be able to hide out in their nests for the journey. Plus, they don’t need a lot of food, can resist drowning and even “hold their breath” and survive on stored oxygen during periods of temporary flooding, the researchers note.

Orlando Brown Jr.'s first order of business as a member of the Bengals? Partner with Cincinnati's mayor in a humorous trailer for the team's Week 17 clash vs. Brown's old squad, the Chiefs.

Brown showed off his acting chops alongside the head of his new hometown.

Check it out here:
The full NFL 2023 schedule will be announced Thursday, May 11.

Pureval famously got into a war of words with Kansas City stars Patrick Mahomes and Travis Kelce when the two sides battled in January for a berth in the Super Bowl. It seemed his words helped to light a fire under KC; Mahomes threw for three touchdowns as the Chiefs sent the Bengals home and marched toward another Super Bowl triumph.

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Back then, Brown was protecting Mahomes' blind side. He switched sides during the offseason, signing a four-year, $64 million deal with Cincinnati to keep rushers from putting Joe Burrow on his back. As such, his loyalties have changed, and in a show of goodwill, he offered Pureval some advice.

"Yeah, I think that was better than last time," Brown said after recording Pureval's vanilla reveal of the New Year's Eve game scheduled to be played in Kansas City. The mayor was far less fiery than when he declared Arrowhead Stadium "Burrowhead" ahead of the AFC championship game.

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Suffice to say, Mahomes and Kelce got the last laugh then. Not only did they vanquish their AFC rivals, they also were loud about it, hopping on the microphone to dish dirt.

"Know your role and shut your mouth, you jabroni," Kelce said, mimicking The Rock.

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Revenge is a dish best served cold. But it's always nice to see someone laugh at themselves after getting caught with their foot in their mouth. Brown's cameo should add intrigue to what is certain to be one of the most-watched games of the 2023 regular season.