Scientists made a claw machine from a dead spider

What’s the weirdest thing you learned this week? Well, whatever it is, we promise you’ll have an even weirder answer if you listen to PopSci’s hit podcast. The Weirdest Thing I Learned This Week hits Apple, Spotify, YouTube, and everywhere else you listen to podcasts every-other Wednesday morning. It’s your new favorite source for the strangest science-adjacent facts, figures, and Wikipedia spirals the editors of Popular Science can muster. If you like the stories in this post, we guarantee you’ll love the show.

FACT: Scientists made a claw machine out of a dead spider

By Rachel Feltman

This story comes from the 2023 Ig Nobel Awards. We’ve talked about a few Ig Nobel winners on the show before. In 2007, the government plans for a so-called gay bomb won the Ig Nobel Peace Prize. Anyway, the Ig Nobels are an annual award ceremony for research that makes you laugh, then makes you think. They were held in September, and one of the stories in particular really stuck out to me.

Last year, researchers from Rice University coined the ominous phrase “necrobotics” to describe a bold new field they’d ventured into. That’s “necro” for dead and “botics” for robotics.

In a move that makes me think of those Big Mouth Billy Bass The Singing Sensation things that got really popular in the late 90s, the researchers used dead spiders to create robotic claw hands.

This started in 2019, when mechanical engineers were setting up their lab at Rice and noticed a dead spider at the edge of a hallway. They got to wondering why spiders always curl their legs up so tight when they die. As any arachnid-expert could have told them, spiders have a hydraulic pressure system that controls their limbs. Basically, a spider’s muscles naturally keep its legs contracted into a closed position. It opens them by applying hydraulic pressure. When they die, they can no longer pump fluid into their little hydraulic legs to keep them open. So they default to their curled up state. The researchers decided to see if they could harness that claw-machine-like mechanism. All they had to do was find a way to pump up the hydraulic pressure.

They landed on inserting a needle into the internal valves that wolf spiders use to fill up their own hydraulics, then super gluing it into place and attaching a syringe full of air. Puffing the air into the spider legs made them open up. You might be surprised to learn this study stirred a bit of controversy from other academics.

In searching for other examples of necrobotics, I came across Custom Robotic Wildlife. They’re a 25-year-old small family business in Wisconsin that specializes in adding high-tech capabilities to taxidermy. Why, you may ask? Usually, it’s to create convincing decoys of wildlife to catch would-be poachers. To learn more about their unique roadkill robots—including some that poop candy—check out this week’s episode.

FACT: Learning to talk to dolphins might help us talk to theoretical aliens

By Laura Krantz

Humans have been broadcasting our presence for about 85 years now, with radio, television, and radar, essentially spamming space with all kinds of messages. Very few of those have actually been deliberate—like the one from the Arecibo Telescope (RIP), or the Doritos commercial we sent out in 2008. But these are essentially messages in a bottle, tossed into the great black ocean of space, and it doesn’t seem likely that anyone or anything is going to come across them. But what if they do? What would we do if something answers back? How on Earth would we even figure out what they’re saying? Enter Dr. Laurance Doyle, an astrophysicist and member of the SETI (Search for Extraterrestrial Intelligence) Institute. He thinks if we really want to get some practice trying to communicate with species other than ourselves, we don’t have to look to space—we’ve got plenty of opportunities right here.

In 1932, a linguist by the name of George Zipf had his students count the letters in the book Ulysses to see how many there were of each letter. What he found is that the second most common letter occurred approximately half as often as the first most common. The third most common occurred one third as often as the first, and so on down the line. Graphed out using a logarithmic scale, this information showed up as a downward 45 degree slope, or a minus one slope. In the end, Zipf plotted dozens and dozens of languages and got that same minus one slope for all of them. This statistical distribution became known as Zipf’s Law and scientists think that if a message obeys Zipf’s Law, it indicates that it’s a real language, that meaningful knowledge is being transmitted.

Now, this was supposed to just apply to human communications. But Laurance and two colleagues, Dr. Brenda Mccowan and Dr. Sean Hanser, had an idea. Dr. Mccowan had recorded and classified the whistles of bottlenose dolphins and so Dr. Doyle graphed her data based on Zipf’s Law—and got a minus one slope for dolphin whistles. The dolphins are talking (which, of course, Matt Groening already knew…). It turns out that several bird species do this as well, including African penguins.

The problem, of course, is that we have no idea what they’re saying. Per Dr. Doyle’s line of thinking, that seems to provide us with an excellent opportunity to practice our translation abilities. Should we ever receive that extraterrestrial message, we might have better luck dissecting it. And, of course, our understanding of how different species communicate here on Earth might give us a sense of how advanced an alien civilization is based on the complexity of the signal.

Check out more stories like this on today’s episode, in addition to my new book, Is Anybody Out There? A Wild Thing Book.

FACT: The oldest living aquarium fish has been around for at least 15 US presidents and maybe as many as 18

By Chelsey B. Coombs

It’s surprisingly difficult to tell how old a fish is. In the past, if you wanted to know a fish’s age, you had to use a ring-counting method like you use with trees, but with these strange calcium carbonate structures located directly behind the brain called otoliths. And unfortunately, that means having to kill the fish, which is obviously bad if you’re working with endangered species like the Australian lungfish.

One Australian lungfish in particular has been around for a looooooong time, and her name is, appropriately, Methuselah. She arrived at the Steinhart Aquarium at the California Academy of Sciences all the way back in November 1938.

Methuselah is a legend and a sweetie who apparently loves figs and getting belly rubs. But no one knew exactly how old she was – they were going off of her arrival date to the museum, which would put her around 84 years old.

Luckily, two scientists, Dr. Ben Mayne of CSIRO, which is like Australia’s NSF, and Dr. David T. Roberts of Seqwater, the Queensland Government Bulk Water Supply Authority, created a non-invasive way to estimate the age of fish using their DNA. That’s important because it helps us predict how populations will grow and we can use that data to aid in the conservation of these important species.

They found that our girl Methuselah is probably around 92 years old, although taking into account the method’s margin of error, she could be as old as 101. And that makes her, as far as we know, the oldest living aquarium fish.