I'm Carl Azuz for CNN 10.

"Worry in our hearts" is how some demonstrators are describing the situation in Sudan's capital.

Their country's military appears to have taken over in another coup⏤Sudan has seen several of those since the late 20th century.

Its former president Omar al-Bashir was a military leader when he seized power in 1989.

He was known for his harsh rule over the Sudanese people and he's been accused of crimes against humanity and genocide in Sudan's Western Darfur region.

During massive civilian protests in 2019, the military took over once again, forcing President al-Bashir out of office.

A transitional government was set up, power was shared between military and civilian groups, but tensions stayed high in the African nation.

In September, forces that were loyal to the country's former president tried and failed to take power back.

And in October, thousands of demonstrators gathered in front of the presidential palace to demand the military take control again while thousands of others amassed in the streets to support the nation's civilian leaders.

So, instability in Sudan is ongoing.

What's happening right now: Sudan's military has broken up its power-sharing government with civilian leaders; it's declared a state of emergency.

It's reportedly arrested government officials, according to witnesses, and the head of Sudan's armed forces says a quote, "independent and fair representative government would take control until a new one is elected in 2023".

Flights have been suspended from the capital's international airport; Internet connections have been severely disrupted.

Sudan's civilian prime minister, who was arrested, has called for the Sudanese to peacefully protest the takeover⏤many people have taken to the streets and there've been some reports of violence against the demonstrators.

Several other countries, including the United States, are speaking out against the apparent military coup and calling for stability in Sudan.

A cold front that plowed across the United States has made its mark.

The National Weather Service says several reports of tornadoes came in as the system moved across Illinois, Kansas, and Missouri, and it was pushing heavy rains and winds over the Appalachian mountains as it moved toward the US east coast.

From New Jersey to Massachusetts, flood watches are in effect through Tuesday afternoon, and authorities said hail and tornadoes were possible in some isolated places.

Meantime, an atmospheric river⏤a band of exceptionally moist air⏤has flowed over northern California and brought heavy rain to the drought-stricken state.

The good news is that this helped firefighters get complete control over the Dixie Fire, the second largest one in state history.

The bad news?

This atmospheric river is dumping rain and bringing wind to hundreds of square miles of northern California, and the big fear⏤mudslides.

Let's look at what happened on State Route 70.

This is in the Tobin area; the hillside came crashing down.

The debris so large that the Caltrans' truck and heavy equipment can't clear it right now; this could be days that this lasts here.

And then as we look over here, I'm on US Route 50.

You can see behind me the South Fork of the American river starting to fill up.

Here, in one shot, you can see they have to be careful with flooding in rivers, but above the so-called burn scar, completely stripped of vegetation in some places.

And when the rain comes down, and it comes down as strong for a sustained amount, that's when you can get the slides; it becomes an ashy, slurry mess⏤that's what they're worried about.

So you will hear about power outages and flash flood warnings with these circumstances, and they're telling drivers unless it's absolutely necessary, you shouldn't be driving.

These are potentially lethal conditions as this atmospheric river comes through northern California.

Reporting from El Dorado County, I'm Paul Vercammen. Now back to you.

10-second trivia: In what mountain range would you find the world's largest salt flat?

Andes, Caucasus, Himalayas, or Rockies.

Salar de Uyuni can be found in the Andes Mountains.

Before I wrote this show, if you'd asked me how many varieties of potatoes there are in this world, I might have said, "Baked, russets, sweet, chips... like, four."

I would have been wrong by about 4,000.

And if you'd asked where most of them are grown, I might have said France, 'cause fries.

But the truth is in the Andes mountains, and the nation of Peru is our next stop.

I can't let them be forgotten because all the flavors, I know now how to grow them, and in that way, I can keep the varieties alive.

At the foothills of the central Peruvian Andes lives Esperanza Gabriel.

She's a potato custodian helping to conserve a personal collection of over 300 ancestral potato varieties.

This one is Suma Suco. Inside, it has pink pulp.

Stef de Haan from the International Potato Center in Lima works with hundreds of custodians like Esperanza.

So you can almost compare them, like, to coin collectors or to stamp collectors.

They are really important because, uh, potato custodians are basically the guardians of the traditional knowledge and they're also the guardians of the diversity itself.

Between the two of us, we have been growing these seeds for 20 years.

Preserving them since the day of our wedding⏤those from my husband's side and those I inherited.

There are about 4,000 varieties of native potato in the world.

And most of them are grown in the Andes, while only a handful are available in supermarkets around the world.

If we don't preserve the whole genetic base of these potatoes, it would basically mean that we have no options in the future to diversify our food system.

So we will be highly dependent on very few varieties, and it would make us extremely vulnerable.

The Andean farmers, where they grow potatoes is very risky.

So, there's a lot of disease pressure, there's a lot of hail, there's a lot of frost, uh... and basically, growing these potatoes together in mixtures is a risk avoidance strategy.

For Esperanza, the motivation is not only protecting diversity, but the simple desire to feed her family.

We grow potatoes to eat, and also for selling as well, and we keep things in storage for us to use throughout the year.

A traditional local dish is pachamanca.

The potatoes steamed underground with hot stones.

You could say that the Andean farmers are really the connoisseurs or the sommeliers of the potatoes.

My mother told me, now I want to teach my daughters so that they can continue cultivating the varieties.

Potato custodians have been protecting seeds for centuries.

For Stef de Haan, valuing traditional agriculture is the only way to ensure biodiversity will evolve and remain available to future generations.

As soon as you put a potato in a gene bank, it becomes something static.

But to farmers, it's really something that is continuously adapting.

So, some things are getting lost, some things are getting added.

It's a laboratory that's not managed by scientists.

Well, i's a laboratory that is basically more than 10,000 years of evolution in the hands of farmers.

Big John is on the move.

That's the name of the largest known triceratops skeleton; it was discovered in South Dakota in 2014.

It was recently sold at an auction in France for $7.7 million, and the buyer was American, so Big John will cross the Atlantic once again.

Paleontologists say the skeleton is about 60% complete; the rest of the bones usually have to be remade, and some scientists don't like private sales of fossils.

But if you collect old artifacts, it's "tricera-tops". Cost a "skele-ton" of money, but it's guaranteed to stop your family in their "tracks" when they see that thing in your home, "don't doubt it".

If the dinosaurs "scores" up your floor, you make no "bones" about it.

No one has a pet triceratops that leave your guests all "glossi-eyed", a "bone-fied" sight with all its might for they're so "fossilized".

Maybe not my best rap, but I'm spitting "artifacts".

Wanna give a shout out to Natchitoches Central High School today; it is located in Natchitoches, Louisiana.

I'm Carl Azuz for CNN.