Learn about a mysterious ancient Roman sauce; puberty happening earlier; and how elephants are getting their tusks back.
Learn about a mysterious ancient Roman sauce; puberty happening earlier; and how elephants are getting their tusks back.
Garum, an ancient Roman sauce, mysteriously vanished — and culinarians can't recreate it by Steffie Drucker
The reason puberty is happening sooner may be because our bodies time it with our nutrition by Grant Currin
Intense poaching led to the evolution of tuskless elephants, but the good news is that those tusks are making a comeback by Cameron Duke
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CODY: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from Discovery. I’m Cody Gough.
ASHLEY: And I’m Ashley Hamer. Today, you’ll learn about a mysterious ancient Roman sauce that experts can’t recreate; the brain receptor that explains why puberty is happening earlier around the world; and why some elephants evolved without tusks — but are finally getting their tusks back.
CODY: Let’s satisfy some curiosity.
Have you ever tried replicating your grandma’s recipe, only for it to not taste the same? That’s exactly what a team of scientists is going through right now. The group is trying to recreate garum (GARE-oom), a fermented fish sauce once beloved by generations of ancient Greeks and Romans — that suddenly disappeared.
Garum was made by leaving heavily salted small fish like mackerel or sardines to decompose in giant vats beneath the Mediterranean sun. The process took months, and it smelled so bad that garum producers were banished to the edge of the city.
But here’s where things get tricky: There were many variations of garum and no official recipe. Whatever records do exist aren’t very exact. Some call for whole fish while others only use the guts. Cooks mixed in different herbs and spices and added honey, oil, wine, or vinegar. Like your grandma, the ancient Romans weren’t precise about recording ingredient proportions. Scientists don’t even agree on the term to refer to the condiment. Some say that “garum” was one particular variety while another version was known as “liquamen.” Its name might have also varied from place to place and throughout history.
Archaeologists have found evidence that garum was being produced and consumed from Tunisia to France. And people from all levels of Roman society enjoyed the sauce. Experts say a bottle of high-quality garum could go for a few hundred dollars today, but there were also cheaper versions that were given to enslaved people.
And while the production process sounds unappealing, food historians say the finished product was mild and quite the taste sensation. Adding just a few drops to a dish caused its flavors to “explode in the mouth.”
The thing is, it’s a mystery as to why something so delicious seemed to have just vanished from history. The leading theories are tied to the fall of the Roman Empire. One possibility is that pirates posed such a threat to coastal garum makers that they abandoned the practice. Another idea is that making garum became too expensive because of heavy taxes on salt after the Empire fell.
While some historians say it’s impossible to recreate this special sauce, you can try some imitations that come close to the real thing. There’s a modern descendant of the Romans’ garum in Southwest Italy that’s known as “colatura di alici” (COLE-ah-TOOR-ah dee-LEE-chee). Other options include the Vietnamese fish sauce “nuoc mam nhi” (nook-mom-knee) or Japanese sauce called “ishiri” (ee-sheer-ee).
So, give it a try and take a lesson from the Romans: Be sure to record your own recipes in detail.
People in a lot of different countries have gotten taller over the last century. And they’ve also been reaching puberty earlier and earlier. The reason isn’t a total mystery: researchers have known for a long time that demographic changes like that can happen as a society gains reliable access to food. But a team of scientists just found the brain receptor that makes it happen. And what it does — and why — have some pretty interesting implications. So let’s talk about it.
The receptor is called MC3R, and it exists because evolution can’t predict the future. Here’s what I mean. For a lot of species — including humans — being bigger and stronger helps with survival. And it’s easier for an individual to have more babies if they get an earlier start. So being big and having babies early are both good things.
But there’s a tradeoff. See, growth and development burn a lot of calories. For individuals who have plenty to eat, that isn’t a problem. But someone without enough food could be in big trouble if their body tried to grow or develop without the nutrients needed to build new tissues.
The newly discovered receptor appears to be the mechanism the body uses to determine if it’s safe to hit the gas on physical growth and sexual development. Here’s how it works. The brain and digestive system coordinate energy consumption using chemical communication. For example, hormones like leptin and insulin tell some neurons to produce neurotransmitters called melanocortins [MELL-lin-no-COR-tins, I THINK]. Scientists already knew that MC4R, or melanocortin 4 receptors used that information from the digestive system to regulate appetite. Researchers have discovered that MC3R, or melanocortin 3 receptors, do something entirely different. It turns out that these newly discovered receptors control the release of hormones that regulate growth and sexual maturity.
The researchers studied these receptors in the lab using mice. They also found 812 women with just 1 of the normal 2 functioning copies of the gene that codes for MC3R. On average, those women were shorter and started puberty nearly 5 months later than their peers. The scientists also found a few children with a MC3R mutation. All of them were shorter and weighed less than average. And one person they found had mutations on both copies of the MC3R gene. That person was very short and didn’t start puberty until age 20.
This research will soon result in genetic tests for mutations affecting the MC3R gene, and that could lead to all sorts of treatments — for example, ones that help patients whose chronic disease keeps them from gaining muscle.
So parents, if you notice your tweens hit puberty sooner than you did? It just means their brains know they’ve got plenty of food to fuel them.
It’s hard to imagine an elephant without tusks, but in Gorongosa [GORE-un-GOZE-uh] National Park in Mozambique, tuskless elephants are surprisingly common. It’s not for a good reason: it’s because of intense poaching. But the good news is that now, the elephants are getting their tusks back.
From 1977 to 1992, Mozambique was boiling over with civil war, and both sides of the war turned to ivory poaching to finance their efforts — ivory that came from elephant tusks. As a result, the war took a heavy toll on the elephants.
Before the war began, the park estimated that roughly 2500 elephants lived within its boundaries. After the war? The first census found fewer than 250 of them. The population has grown in the decades since, but it hasn’t achieved its pre-war numbers.
Aerial photos from before the war began showed that roughly 18 percent of the elephants were tuskless, but after the war, that number had risen to 50 percent. Tusks are usually really important for elephants: they use them to defend themselves and gather food. But ivory poaching had turned that survival advantage into a burden. This wasn’t new information, though. We already knew that the war had led elephants to gradually lose their tusks. What we didn’t know is why all of the tuskless elephants were female.
Scientists figured it out using whole-genome analysis. They discovered that the ability to be born tuskless is a trait that’s carried on the X chromosome. Both male and female elephants have an X chromosome — females have two, and males have one X and one Y. The scientists realized that the reason why tuskless males don’t exist is that having a solo X chromosome with a tuskless gene variant is fatal. But because female elephants have two X chromosomes, they can carry the trait on one, and the other X chromosome with a normal variant can protect them from too much harm. Males, with only one X chromosome, aren’t so lucky if their version of the gene happens to be defective. And in fact, one of the candidate genes is actually linked to a similarly fatal disorder in humans that also affects only males.
The good news, the researchers found, is that as the population grows, fewer and fewer females are being born without tusks. In ten years, it’s dropped from 50 percent of the population to 30 percent. And it’s still falling. In a world without ivory poaching, the trait may very well disappear. And we’ll be back to a world where every elephant has big, glorious tusks the way nature intended.
Let’s recap the main things we learned today
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CODY: Today’s writers were Steffie Drucker, Grant Currin, and Cameron Duke.
ASHLEY: Curiosity Daily is distributed by Discovery.
CODY: [AD LIB SOMETHING FUNNY] Join us again next time to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!