Learn about why asteroids can have rings; spiders that actually nurse their young; and Tāne Mahuta, a massive tree that’s been known to bring visitors to tears. In this podcast, Cody Gough and Ashley Hamer discuss the following stories from Curiosity.com to help you get smarter and learn something new in just a few minutes: Asteroids Can Have Rings, Too — https://curiosity.im/2SeUiK6 Spider Milk? Jumping Spider Mothers Actually Nurse Their Young — https://curiosity.im/2SmDgKj The "Lord of the Forest" Is a Massive Tree Known to Bring Visitors to Tears — https://curiosity.im/2SenhxM If you love our show and you're interested in hearing full-length interviews, then please consider supporting us on Patreon. You'll get exclusive episodes and access to our archives as soon as you become a Patron! https://www.patreon.com/curiositydotcom Learn about these topics and more on Curiosity.com, and download our 5-star app for Android and iOS. Then, join the conversation on Facebook, Twitter, and Instagram. Plus: Amazon smart speaker users, enable our Alexa Flash Briefing to learn something new in just a few minutes every day!
Learn about why asteroids can have rings; spiders that actually nurse their young; and Tāne Mahuta, a massive tree that’s been known to bring visitors to tears.
In this podcast, Cody Gough and Ashley Hamer discuss the following stories from Curiosity.com to help you get smarter and learn something new in just a few minutes:
If you love our show and you're interested in hearing full-length interviews, then please consider supporting us on Patreon. You'll get exclusive episodes and access to our archives as soon as you become a Patron! https://www.patreon.com/curiositydotcom
Learn about these topics and more on Curiosity.com, and download our 5-star app for Android and iOS. Then, join the conversation on Facebook, Twitter, and Instagram. Plus: Amazon smart speaker users, enable our Alexa Flash Briefing to learn something new in just a few minutes every day!
Full episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/how-asteroids-can-have-rings-spiders-that-nurse-their-young-and-lord-of-the-forest-tane-mahuta
[MUSIC PLAYING] CODY GOUGH: Hi. We've got three stories from curiosity.com to help you get smarter in just a few minutes. I'm Cody Gough.
ASHLEY HAMER: And I'm Ashley Hamer. Today you'll learn about why asteroids can have rings, spiders that actually nurse their young, and a massive tree that's been known to bring visitors to tears.
CODY GOUGH: Let's satisfy some curiosity. We all know that Saturn has incredible rings surrounding the planet. But did you know that even smaller bodies can host rings? That's right. Scientists now know that even asteroids can be surrounded by these celestial hula hoops. But it turns out, the physics behind big rings is totally different from the physics behind small rings.
ASHLEY HAMER: So first, here's what we know about rings. In general, rings are just tight orbiting clouds of ice, rock, and dust. But we're still learning a lot about where planetary rings came from and how they behave. NASA's Cassini mission collected a lot of data from Saturn's rings in 2017. One thing we now know is that Saturn's rings are made up of debris of all sizes, from particles as small as a grain of sand to boulders as large as a whole mountain.
CODY GOUGH: But here's a surprise. Asteroids have rings too. Scientists discovered rings around an asteroid called Chariklo in 2014, then found a circle of debris surrounding a dwarf planet called haumea in 2017. A new study in Nature Astronomy explains how these little bodies can hold on to their rings in the absence of shepherding moons, which help hold together rings around planets. The researchers have a couple of explanations.
ASHLEY HAMER: The first explanation is that if the body is spinning quickly enough, it can create a resonance that stops rings of debris from expanding and dissolving. The second ring-saving influence is if the asteroid or dwarf planet has a huge center of mass on its surface, like a mountain. This keeps the ring hovering over its home object rather than being torn apart by tidal forces.
CODY GOUGH: One of the study's co-authors puts it this way, quote, "In the case of Chariklo, the irregularities confine the rings. In the case of Haumea, the body's big flatness does the job," unquote. Maybe someday we'll figure out how to get a ring around Earth. You know why we would do that, Ashley?
ASHLEY HAMER: Why do we do that, Cody?
CODY GOUGH: Because if you like it, then you should put a ring on it.
ASHLEY HAMER: Yup.
CODY GOUGH: [LAUGHS]
ASHLEY HAMER: The checklist for being a mammal is pretty straightforward. You need to be warm blooded. You need to have body hair. And you need to nurse your young. So imagine scientists' surprise when they discovered that a spider, an invertebrate that is definitely not a mammal, produces milk and nurses its young.
CODY GOUGH: Ashley, talk to me about the rabbit hole that sled you down.
ASHLEY HAMER: Yeah. I found out that a lot of non-mammals produce something akin to milk, like cockroaches, tsetse flies, pigeons. That was really gross.
CODY GOUGH: This is all disgusting.
ASHLEY HAMER: Yeah. Milk gets really gross really fast.
CODY GOUGH: Well, we'll try not to gross people out too much. [CHUCKLES]
ASHLEY HAMER: Yeah. We'll stick to the spider. I'm talking about a jumping spider known as Toxeus magnus. It looks less like a spider and more like an ant, and it doesn't really act like a spider either. Usually, once a spider hatches and gets strong enough to find its own food, it sticks out on its own as a lone hunter.
But T. magnus spiders live as happy little family in a single nest, often with two or more adults or one adult female and several baby spiderlings. With that whole nest thing going on, researchers in China wanted to see if the mother spider also took care of its young as they matured. And they found that the mother spider was producing a sort of milk for her offspring.
For the first week, she left droplets of it around the nest for her spiderlings to find. But eventually, the baby started sucking directly from her, for lack of a better term, teat. Though technically, the milk came out of her epigastric furrow, which is a genital structure in her abdomen. The spiderlings kept nursing for about a month and a half. But even after they were done nursing, they kept using the nest at night. Those darn slacker teenagers, am I right?
We found a few other non-mammals that make milk to feed their young. But according to the researchers, this jumping spider is the only invertebrate known so far to nurse its young like a mammal. They say it's a sign that scientists need to reevaluate how common this tendency is across the animal kingdom, both in invertebrates and other organisms. Once again, science proves to be more complex than our clean definitions can handle.
CODY GOUGH: As a fan of comic books, I'm just glad Peter Parker didn't get bitten by a radioactive jumping spider. Spider-Man might be a bit different.
ASHLEY HAMER: Oh, Spider-Mama.
CODY GOUGH: [LAUGHS] (SINGING) Spider milk, spider milk. Gross. You may not like spiders, but I bet you like trees. Let's end with something beautiful, a tree called Tane Mahuta, nicknamed the Lord of the Forest. It's a massive tree known to bring visitors to tears.
Now Ashley, you grew up by the redwoods, so you're no stranger to tall trees.
ASHLEY HAMER: Yeah. There's no tree better than an old-growth redwood in my book. You can't convince me otherwise.
CODY GOUGH: These trees actually aren't as tall as redwoods, but they are big around.
ASHLEY HAMER: Yes.
CODY GOUGH: Like you cannot hug around these trees. So this is like the New Zealand version of old-growth redwoods. Tane Mahuta is the largest kauri tree in the world. For some perspective, the coastal redwood trees here in the US can grow to be around 300 feet or 90 meters tall, while kauri tree is usually grow to about 1/3 of that height.
But again, they are wide. An average kauri tree is more than 16 feet, or 5 meters around. But the Lord of the Forest, named after a Maori forest god, is a staggering 50 feet around and 148 feet tall. That's 16 meters around and 45 meters tall, which makes it about as tall as a 14-story building.
It takes a long time for a tree to reach that height. And Tane Mahuta is estimated to be about 2,500 to 3,000 years old. That means it was a sapling when humans were first entering the Bronze Age. Besides their stunning appearance above ground, kauri trees set themselves apart with a uniquely shallow network of roots. And lots of very large trees nourish themselves on mineral deposits deep beneath the ground.
But kauris extend thin tendrils along the surface, and they feed off of decomposing organic matter. They have deep peg roots to hold them down since they're so huge, and they don't gather any nutrients. Unfortunately, that feeding system also leads the giants vulnerable.
In recent years, the trees have been suffering from a new disease known as kauri dieback. It's caused by outside contaminants seeping into those shallow roots, sometimes by wandering mammals and sometimes on the soles of visiting hikers. That's why if you're going to visit Tane Mahuta, you actually need to hose off your shoes before you do so.
You can see pictures of the Lord of the Forest and read about all of today's stories on curiosity.com and on our free Curiosity app for Android and iOS. But you won't find the Entwives, which are still missing. Where are the Entwives?
ASHLEY HAMER: It is New Zealand. I mean, you'll be closer.
CODY GOUGH: Oh, yeah. Where they shot Lord of the Rings.
ASHLEY HAMER: Yeah.
CODY GOUGH: Peter Jackson, you heard it here first. Get that Netflix documentary going. We need to find the Entwives.
ASHLEY HAMER: Join us again tomorrow with the award-winning Curiosity Daily and learn something new in just a few minutes. I'm Ashley Hamer,
CODY GOUGH: And I'm Cody Gough.
ASHLEY HAMER: Stay curious.
NARRATOR: On the Westwood One Podcast Network.
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