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00:00:012019 was a year filled with astonishing discoveries on Earth and beyond.
00:00:08We inched closer to immortality,
00:00:12recovered and restored our heritage,
00:00:16and science fiction became science fact
00:00:19when we saw the unseeable for the very first time.
00:00:30It's hard to imagine anything more terrifying than a galactic vacuum cleaner that devours planets and even stars.
00:00:45Einstein predicted the existence of black holes in 1916,
00:00:49and researchers confirmed them in 1971.
00:00:54But, though plenty of indirect evidence was collected over the last half century,
00:00:59black holes are extremely camera shy.
00:01:02Scientists hadn't actually seen one until this year,
00:01:06thanks to an unprecedented global effort and the Event Horizon Telescope.
00:01:12The EHT is made of radio telescopes working in concert all over the Earth.
00:01:19This is possible because of one powerful feature.
00:01:23Interferometry doesn't care how far the antenna dishes are separated,
00:01:27as long as they're precisely synchronized.
00:01:31The combined antenna work as though they're a single telescope,
00:01:35with a collecting surface as big as the distance between them.
00:01:40With antenna located in Hawaii, North and South America, Greenland, Europe, and the South Pole,
00:01:49the EHT has a collecting surface literally the size of the Earth.
00:01:56The project began three years ago,
00:01:58when a team connected millions of gigabytes of data from a remote galaxy known as M87.
00:02:06The data sent from the vast network of telescopes was often spotty and random,
00:02:11so they figured out how to fill in the gaps by applying several algorithms.
00:02:17The result? A complete and groundbreaking image of a lopsided, ring-like structure.
00:02:23A black hole in the center of the distant galaxy.
00:02:28Now, history is being made. A direct photograph has just been released.
00:02:34And we are delighted to be able to report to you today that we have seen what we thought was unsealed.
00:02:42We have seen and taken a picture of a black hole.
00:02:46Here it is.
00:02:50And this is the strongest evidence that we have to date for the existence of black holes.
00:02:59And it is also consistent, the shape of this shadow, to the precision of our measurements with Einstein's predictions.
00:03:11Black holes come in sizes ranging from nanoscale to thousands of times larger than our entire solar system.
00:03:19The diameter of M87 is roughly 24 billion miles across.
00:03:23It's an object where the physical realm, and the laws of physics as we know them, have broken down.
00:03:33And yet, it retains the gravity of all the mass of every object it has ever devoured.
00:03:42So, this is an easy way to visualize how a black hole shadow is formed.
00:03:46We can start by looking at what happens to light when we have just flat space.
00:03:51And as our normal experience is, light just follows straight paths.
00:03:56But if I put a black hole in the middle, the black hole will warp the space-time all the way to the singularity.
00:04:01It takes light rays and bends them.
00:04:04And some of them actually go straight down the neck of the singularity.
00:04:08A shadow is what a black hole casts on its surrounding emission.
00:04:12So, as gas gets close to the black hole, it heats up, it emits light.
00:04:19The black hole spacetime, with the presence of the horizon and with the presence of a density depression at the center,
00:04:28absorbs all the light there.
00:04:30So, it leaves a central darkness, which we call the shadow that the black hole imprints on the image.
00:04:35And the Earth Horizon Telescope is just getting started.
00:04:40Data gathered from the various Earth-based locations is now being processed
00:04:45to reveal a new image of an altogether different black hole,
00:04:49and will be released to the public in the coming months.
00:04:51As scientists continue to probe these mysterious cosmic monsters,
00:04:59they'll be able to puncture even more myths about how our universe was born.
00:05:10And liftoff of the Cassini spacecraft on a billion-mile trek to Saturn.
00:05:15Each of the planets in our own solar system has a unique appearance and personality.
00:05:19Especially Saturn, with its iconic rings.
00:05:25Rings of ice and rock that extend up to 175,000 miles outward,
00:05:31yet only average 30 feet in height.
00:05:38NASA's Cassini space probe spent 13 years studying Saturn and its rings,
00:05:43before plunging to its death in 2017.
00:05:45But it left behind a wealth of data for researchers back home.
00:05:50Early this year, new information revealed that perhaps Saturn's rings formed only between 10 million and 100 million years ago,
00:06:00at a time when dinosaurs roamed Earth, and not during the birth of our solar system.
00:06:04The majestic gas giant may have once existed without its distinctive halo.
00:06:11We used to think of rings as these individual particles kind of bumping into each other and sort of floating around in space.
00:06:22And we now know that the bulk of Saturn's main rings, the particles actually stick together.
00:06:29And they form these long strands that we call wakes, and that these wakes line up like the rows of a marching band.
00:06:36They have grooves, if you like, like an old-fashioned record, created as wakes of moons which are orbiting. Some of the moons are in the rings, some of those moons are outside the rings, and these waves give an interesting texture.
00:06:53They break apart and they reform, so there's this beautiful cosmic dance going on inside the rings.
00:07:04And Cassini wasn't the only one getting in on the action.
00:07:08New ground-based telescope observations have identified 20 new moons orbiting Saturn, bringing the total to 82, beating Jupiter by three.
00:07:17So we found these Saturn moons using the most powerful survey telescope in the world.
00:07:23It's the Subaru telescope, which is eight meters in size.
00:07:27And it has the largest camera.
00:07:30It's the size of a small car.
00:07:32And it can cover six full moons in one image.
00:07:35And then during the early solar system, there's a lot of stuff flying around.
00:07:39There's a lot of comets and asteroids, many more than there are now.
00:07:42And so it's likely that these moons were hit by comets and asteroids that are just flying past Saturn.
00:07:49And that's why we see, basically, a lot of fragments from these collisions.
00:07:54The small moons, measuring only a few miles in size, orbit the outer edges of Saturn.
00:08:01And many more could be hiding in plain sight.
00:08:04We're actually tracking more moons.
00:08:07And a lot of these moons are just on the edge of our detection.
00:08:09We can just barely see them.
00:08:12Saturn really is the moon king.
00:08:17On February 1, 2019, members of the Mars exploration team gathered at NASA's JPL Headquarters to say their final goodbye to one of space exploration's greatest pioneers, the Opportunity Rover.
00:08:31I wanted to say, with the completion of tonight's commanding, this concludes operations for MER1, spacecraft ID 253.
00:08:41And on behalf of the entire MER project, we'd like to thank the DSN for over 15 and a half years of outstanding support from launch until tonight.
00:08:49Thank you for your comments.
00:08:51Thank you for your comments.
00:08:53It's a tie for all of us.
00:08:5714, you are released.
00:09:02It all began 15 years ago.
00:09:05The control room had a much different feel to it.
00:09:08One of excitement and, shall we say, opportunity.
00:09:11Opportunity.
00:09:13And it all started with one photo.
00:09:17When Opportunity sent back that first picture from Eagle Crater, that night is like burned in my brain, I will never forget it.
00:09:24It was such a dramatic image of Mars and it was so different than any images we've seen before.
00:09:29Opportunity, packed with tools and instruments, was a wandering geologist, probing the planet for information and searching for signs of liquid water.
00:09:50Opportunity lands right from the get-go discovery of water-formed rocks, right?
00:09:54You know, it came easy.
00:09:55Here, she found little so-called blueberries that contained hematite and iron ore.
00:10:01It's an iron mineral that forms in areas with a lot of water.
00:10:06By the end, Opportunity traversed more than 28 miles of Martian landscape, sharing more than 225,000 images of its surroundings with researchers back on Earth.
00:10:20Perseverance Valley, believed to be a water-formed gully, was Opportunity's final destination.
00:10:31It was here, on June 10th, 2018, Seoul 5,111, that Opportunity sent its last message.
00:10:45Creatively and poetically translated by media outlets as,
00:10:48My battery is low, and it's getting dark.
00:10:54This, as a massive and devastatingly dense dust storm approached.
00:11:00And so the rover couldn't generate any energy with that.
00:11:04And so we saw the rover just shut down.
00:11:05And there was nothing we could do at that point, because it didn't have power to keep going.
00:11:12And we just had to wait.
00:11:14And that's what we did do, is wait and wait and wait.
00:11:19This is its last panoramic view.
00:11:22Eight months later, NASA would designate Opportunity lost.
00:11:27Its mission complete.
00:11:29It taught us how to do surface operations.
00:11:35It taught us how to read the terrain and navigate and plot a safe path from one point to another.
00:11:42We did not know how to do those.
00:11:44It was all speculative.
00:11:46But new rovers are on the way.
00:11:522019 was a very big year for Mars exploration.
00:11:54We've sent unmanned spacecraft to the fourth planet from the sun since the 1970s.
00:12:03But NASA's InSight is the first to probe into the heart of the red planet.
00:12:10InSight uses cutting edge instruments to investigate internal processes
00:12:15that likely formed all of our terrestrial planets.
00:12:19Taking Mars daily temperature and planetary pulse.
00:12:24The basic idea of InSight is to map out the deep structure of Mars for the very first time.
00:12:32We're going to map out the thickness of the crust, the size of the core,
00:12:36sort of get the first map of the inside of Mars.
00:12:40We don't know very much about what goes on 2,000 miles below the surface.
00:12:45And this will be the first mission to investigate the huge extent of Mars below the surface.
00:12:50But brand new technology doesn't come trouble free.
00:12:56InSight's HP-3, the mechanical mold designed to burrow 16 feet down into Martian soil,
00:13:03got stuck at just 12 inches down soon after landing.
00:13:06Stuck on Earth, 140 million miles from Mars, engineers are working to determine if the stumbling block is a rock,
00:13:17or if the problem lies with the unusual composition of the Martian soil.
00:13:21The lander has detected several small Mars quakes.
00:13:31The tremors are much weaker than medium-sized earthquakes,
00:13:35confirming their suspicions that Mars is much more placid than tectonically active Earth.
00:13:40NASA's family of fearless Martian rovers have unlocked many of the Red Planet's secrets.
00:13:54From Little Sojourner's first trip 22 years ago,
00:13:58to Twins, Spirit and Opportunity,
00:14:01and finally, the Curiosity rover.
00:14:04But it's time for a new generation of explorers.
00:14:06NASA plans to fly the first heavier-than-air spacecraft on another world,
00:14:12the Mars helicopter.
00:14:16The Superbird is being tested right now.
00:14:23We've built the helicopter that will go to Mars,
00:14:27and at this time, we've shown that it can fly.
00:14:30We've done the flight test in the chamber with the thin atmosphere representative of Mars.
00:14:37In JPL's 25-foot-wide vacuum chamber,
00:14:41the helicopter team recreated the gravity and flying conditions of the Red Planet
00:14:46to test the Mars helicopter.
00:14:48The vehicle's good to go for a July 2020 launch.
00:14:51But really, our job isn't done until we see the same test flight being performed at Mars.
00:14:59So next time we fly, it'll be at Mars.
00:15:02But that's our ultimate goal.
00:15:04That's when we'll go, yes.
00:15:08Drones are the perfect way to investigate far-away worlds,
00:15:11especially in the search for extraterrestrial life.
00:15:16Titan, Saturn's largest moon, tantalizes scientists
00:15:21because it seems to hold all the ingredients for life that were present on early Earth.
00:15:28And this year, a new mission has been approved to explore this alien world.
00:15:33NASA's Dragonfly drone is part of a New Frontiers mission.
00:15:37The eight-rotor drone, expected to be the same size as the Curiosity rover on Mars,
00:15:43will also carry many of the same instruments and will launch in 2026.
00:15:48Because Dragonfly will fly over instead of rolling on,
00:15:53it has the potential to cover far more territory.
00:15:56With speeds reaching 22 miles per hour, who knows what it will find?
00:16:01Dragonfly was designed to be a rotorcraft to explore Titan
00:16:04because it's the right way to explore the Titan environment.
00:16:07It's the right way to make the measurements we need to
00:16:10to understand the chemistry of this ocean world.
00:16:13There are sand dunes, there are clouds,
00:16:15you even have methane rain, there are methane rivers and lakes and seas.
00:16:19The organic chemistry in Titan's atmosphere and on its surface
00:16:23may replicate the type of organic chemistry we had here on Earth before life developed.
00:16:28We want to be able to understand how life took the step from chemistry to biology.
00:16:34While NASA and other agencies pioneer flight through space,
00:16:3878 years ago the first operational jet fighter plane was the engineering masterpiece of its time.
00:16:44The German Messerschmitt Me 262 set the course for the future of aviation history.
00:16:50If the Nazis had been able to access more refined metals for the jets' engines,
00:16:54if they'd had more fuel reserves and more time, then things might have played out very differently toward the end of World War II.
00:17:03Bomber crews had to have been terrified. The German airplane is almost 100 miles an hour faster.
00:17:09No one has flown a genuine example of this revolutionary machine since the 1950s,
00:17:14but it's now nearly ready to take to the skies once again.
00:17:21It's been a 19-year effort to realize the dream of the late Vulcan founder and pioneer of Microsoft,
00:17:27Paul Allen, to restore the plane to precise historical accuracy.
00:17:32During the war, because of extreme pressure to win, that really accelerates the progress of technology
00:17:37and these engines are an example of the amazing leaps that happened because of that pressure.
00:17:42In 2000, the plane traveled across the world, where engineers have stripped the plane down to its component parts.
00:17:49Basically, it came in a big wooden crate, pretty much a rust bucket.
00:17:54Then painstakingly rebuilt it, piece by piece.
00:17:57Up until the last year, we didn't know where the light at the end of the tunnel was.
00:18:06And with the success of the first engine tests, the ME-262 will attempt to take flight before year's end.
00:18:12A grim legacy of the same war has been discovered at a site of much earlier, but legendary tragedy.
00:18:32Over the years, archaeologists working in Pompeii, the famous archaeological site, have discovered unexploded bombs dropped by the Allies in World War II.
00:18:50Another surfaced and was deactivated at the beginning of the first large-scale excavation in Pompeii in 70 years.
00:18:57Nearly 2,000 years after the site was engulfed in ash by the eruption of Mount Vesuvius.
00:19:08New finds at the famous site are rewriting everything we thought we knew about the deadly day in AD 79.
00:19:15Italian archaeologists have removed 24 feet of volcanic debris and have discovered brilliant murals and mosaics that remained hidden until now.
00:19:25New skeletons reveal more about the last minutes of aristocrats and slaves that never made it to the gates of the doomed city.
00:19:35But at the edge of the new excavation, archaeologists have discovered that they were not the first on site.
00:19:41In antiquity, and even recent times, looters have dug a series of tunnels under the street, into this stable of a once grand villa.
00:19:54The tunnels, some as long as 60 meters, led to neighboring homes. At night, using lanterns and lamps, the looters broke through the walls looking for precious objects of value.
00:20:07The tunnels, some as long as 60 meters, led to neighboring homes. At night, using lanterns and lamps, the looters broke through the walls looking for precious objects of value.
00:20:19In contrast, archaeologists carefully removed the ash, layer by layer, searching for evidence of what happened here.
00:20:37In contrast, archaeologists carefully removed the ash, layer by layer, searching for evidence of what happened here.
00:20:49The illegal diggers had partially cut through it, damaging the chance for a second mold.
00:21:08A good part of the horse, we see here three of the arms of the horse, there we begin to delineate the back of the horse.
00:21:26The head is probably down here, under the menu, where perhaps the horse had to be attached,
00:21:32so it was impossible to escape because it had to be attached here.
00:21:38As a result, the
00:22:08faster than the flight.
00:22:12Of course, the discovery of the horse was sensational
00:22:16and it was an extraordinary emotion for us.
00:22:20We worked on it because we didn't expect it, frankly.
00:22:38During the fourth surge, gas and pumice traveling at more than 150 miles per hour enveloped the city of Pompeii.
00:22:51It's now known that most victims died instantly from the 600-degree superheated air,
00:22:57but the ash continued to fall at the rate of 6 inches per hour.
00:23:05West of Vesuvius, Herculaneum escaped the first lethal blanketing,
00:23:10but just before midnight, another surge.
00:23:14This one, a burning wall of volcanic mud, engulfed the smaller town.
00:23:21This pyroclastic flow quickly carbonized, encapsulating wood and other fragile materials with a thick black crust.
00:23:30Papyrus scrolls discovered in 1752 were so fragile that every attempt to unwrap them through the centuries
00:23:39immediately caused them to crumble.
00:23:42These papyri are the only original literature to have survived from the classical world,
00:23:48so researchers are desperate to unwrap and read them.
00:23:52They are the canonical example of material from antiquity that is both too fragile to open,
00:24:02and also so valuable and mysterious that it has captured the attention of scholars for many years.
00:24:09Now, by applying subatomic physics, originally designed for medicine, they might have found a way.
00:24:16And then how many slices do you have to make up the whole run of the scroll?
00:24:20I mean, maybe 12,000?
00:24:22Right.
00:24:23That's a lot of data, right?
00:24:25Coupled with a sure-fire confidence in methodology,
00:24:29which drives seals to his most ambitious projects and ultimate successes,
00:24:35including the 2016 virtual unwrapping of a third-century Hebrew scroll known as the En Gedi scroll.
00:24:46Using x-ray to peer inside the badly damaged rolled-up animal skin,
00:24:50seals and his team laid out the artifact's geometric volume without ever opening it,
00:24:56highlighting the text within.
00:25:05The complex scanning of the Herculaneum scrolls took place over multiple days this summer in California,
00:25:10as a team of international researchers held their breath as they unraveled history.
00:25:17Well, you know, my expectations are always different from everyone else's.
00:25:23I expect things to happen quickly, but what's probably going to happen is that we will not see the complete text right away
00:25:31because there are too many computational steps involved in being really deliberate and systematic about our work.
00:25:37But when dealing with 2,000-year-old documents, what's a few months mean to learn the secrets held within?
00:25:44The prospect of non-invasively, virtually, unwrapping these scrolls and reading their texts is a very exciting breakthrough,
00:25:55and scholars will potentially have access to a text that's complete, that's whole and undamaged.
00:26:02The scrolls are immensely valuable in the sense that it's the only library from antiquity that has ever been discovered in place.
00:26:27All libraries from antiquity have been lost.
00:26:32Throughout history, fire has been one of the most spontaneous and unstoppable forces of destruction.
00:26:392019 saw a massive increase in wildfires around the globe.
00:26:45Siberia, Alaska, the Amazon, are all going up in smoke.
00:26:56Fast-moving fires can burn millions of acres of land and consume everything, trees, homes, even humans, in their paths.
00:27:07Ongoing research in 2019 is revealing new and aggressive ways to combat wildfires.
00:27:14So this vehicle is called the M-Star, Mobile Special Technology and Aerial Response.
00:27:20Typically we will carry one, two, three, four primary drones.
00:27:27You want to get on scene and get a drone in the air quickly.
00:27:30The next phase in wildfire technology is integrating drone usage and most likely it's used to map fires.
00:27:39Because you can put cameras on these and you can put infrared cameras and you can fly in very complex terrain, smoky conditions.
00:27:46So that's a new tool that firefighters will be utilizing.
00:27:49Drone pilots go out and fly to do mapping.
00:27:52They come back with an SD card that has all the pictures they've taken.
00:27:56I put it in my card reader.
00:27:58I'm using the software I have on here to go and stitch those things together, create an image,
00:28:02and maybe display that image outside to the commanders.
00:28:12Meanwhile, this vehicle actually is equipped with mini cameras.
00:28:15There's a camera on the front, the rear, and both sides, as well as on top of the mast.
00:28:20So I can see to maintain situational awareness of what's going on in the incident command post.
00:28:25But I can also at the same time see what the firefighters are doing on the inside of the fire.
00:28:29So this could be my firefighters on the inside, walking around.
00:28:34I think there's a lot of room for technology to improve the way that we fight wildland fires
00:28:41and the way that we prepare for wildland fires.
00:28:44Fire management agencies should be utilizing the current state of the science and technology.
00:28:51It takes a high-speed thermal camera, and then inside there's an optical frame.
00:28:56And if your vision is occluded by smoke, the thermal camera just puts a green line around what you would be seeing.
00:29:03It's the small changes that make a big difference. Then your firefighters have a chance.
00:29:08If you look at the number of firefighters in the United States 30 years ago, it was about a million firefighters across the United States.
00:29:15Today, 30 years later, it's about a million one, million two.
00:29:18Almost the same number of firefighters, but the number of fires, number of incidents, number of calls have gone up.
00:29:24So how do you get to the point of doing more with less or more with the same?
00:29:29And the answer, of course, is technology.
00:29:32And no one could have used these advancements more than the brave souls combating this year's raging fires in South America.
00:29:39The Amazon rainforest lost almost 4,000 square miles to fires in the first 26 days of August 2019 alone, according to data from the Brazilian government's satellite monitoring agency.
00:29:55There is nobody here. There is nobody to stop it. And it just goes on for mile after mile.
00:30:02The Amazon rainforest is over 2 million square miles of jungle in South America. Billions of trees.
00:30:14But its health is important to the whole world. Without it, carbon dioxide would warm the atmosphere and oceans faster, changing weather patterns.
00:30:25The trees absorb and store carbon dioxide through their leaves.
00:30:29One tree can absorb the equivalent of a car burning eight liters of gasoline, or 48 pounds per year.
00:30:37But when there's a mega drought, coupled with fires, it stresses the forest and releases tons of carbon dioxide, contributing to the greenhouse effect.
00:30:48The canopy, of course, is where the plant is taking in carbon dioxide from the atmosphere,
00:30:53where the leaves are absorbing carbon dioxide and being stored up in the branches and the trunks and the roots.
00:30:59The plants take out carbon and carbon dioxide, and they release oxygen.
00:31:05All forests actually provide oxygen for the rest of life on Earth.
00:31:11This giant forest stores vast quantities of carbon dioxide.
00:31:17CO2 emissions are rising faster than models predict.
00:31:23Of the carbon dioxide we pump out every year, from factories, cars, power stations, and agricultural burn offs,
00:31:2940% is absorbed by the atmosphere, 30% is absorbed by the oceans, and 30% is absorbed and stored by forest ecosystems.
00:31:41The Amazon absorbs the largest amount of carbon of any rainforest in the world.
00:31:47With this mega-fire that's occurring in the landscape, it's really a dark scenario, I would say, for the future of the Amazon.
00:32:01Hundreds of billions of trees are going up in flames.
00:32:05And all these trees that once absorbed CO2 are now dead and releasing it into the atmosphere.
00:32:12The question is, will more fires push the Amazon rainforest to the point of no return?
00:32:22And how close are we already?
00:32:26Climate scientists say, if temperatures do rise by 3 or 4 degrees this century,
00:32:31the Amazon rainforest won't absorb the great volumes of CO2 it currently does.
00:32:37Or worse, it'll begin to produce more CO2 than it absorbs.
00:32:42And our planet as we know it will change forever.
00:32:47Already, climate change is having a grim effect on our fragile planet.
00:32:53July 2019 was the hottest month in recorded history for our planet.
00:32:58July 2019 was the hottest month in recorded history for our planet.
00:33:01According to NOAA, polar ice melted to record lows,
00:33:04while worldwide summer temperatures soared to new heights.
00:33:07Earth has experienced global warming in the past,
00:33:12but never at this speed and with this intensity.
00:33:15It begs the question, what life forms will be left on Earth?
00:33:21Possibly, parasites?
00:33:24Groundbreaking research reveals that creatures that live on other organisms,
00:33:29at the expense of their hosts, make up half of all known species on Earth.
00:33:35Being a parasitologist, it's sort of like every day is your birthday.
00:33:39You have this present in front of you and you open it up.
00:33:42You don't know what's going to be inside it, but usually it's something cool.
00:33:45There's a jar of raccoon rat worms.
00:33:47Sometimes it's something you've never seen before.
00:33:49Sometimes it might be something that nobody has ever seen before.
00:33:53Parasites can be deadly.
00:33:56In 2017, malaria caused an estimated 435,000 deaths globally,
00:34:02almost 85% occurring in Africa and India.
00:34:06However, parasites in the salt marshes of Southern California
00:34:11may help paint a broader picture of how they fit into our ecosystem.
00:34:16One of the things that we've learned is that parasites are really everywhere.
00:34:21There are so many parasites around us all the time that we just don't see.
00:34:26You've got this species of snail that's basically hundreds per square meter sometimes, like this.
00:34:33And then the trematodes that are in most of these guys, we think, they castrate the snail for life.
00:34:40They're sitting in the gonads and they multiply asexually and they fill up the gonads and they just munch away as the new gonads produce.
00:34:46And then if you open up an infected one, it's just this mass of worms in place of where the gonads should be.
00:34:52And as far as we know, the snail doesn't notice the difference.
00:34:55And instead of making snail babies, it makes parasite babies.
00:34:59Most of the parasite's extreme adaptations are ultimately about reproduction.
00:35:05The larvae in the snails grow into a trematode worm that keeps moving from one host to another as it develops.
00:35:15Since it can reproduce only in the gut of shorebirds, it makes the transition through an unusual route, the brain of a fish.
00:35:24What we think is that this parasite has had this adaptation to basically sit on the brain of the fish, control its behavior, mind control in a way.
00:35:34And that puts the parasite in the driver's seat because when they're infected, they'll do things like they'll roll over and show that bright white belly up in the air so a predatory bird is more likely to see them.
00:35:48The parasite's not using a sledgehammer to do this, it's using finely tuned chemical manipulation.
00:35:58The unlikely odyssey of the trematode parasites doesn't come to an end when they reach the bellies of birds.
00:36:04The cycle begins all over again as the birds spread millions of parasite eggs in their droppings.
00:36:10You know, the birds are really the top of the food chain here, and of course, in doing that, they're also the final host for so many of the parasites that are out here.
00:36:20There's just as much parasite biomass in this salt marsh as there is bird biomass.
00:36:25So the extent that we think that the birds are important players in this salt marsh, then I think we also have to think of the parasites as being important players too.
00:36:33It may take us some time to get used to the idea that parasites are a vital part of every ecosystem.
00:36:43252 million years ago, humans weren't around to impact which species failed and which thrived.
00:36:52Paleontologists in Norway just discovered that after the Permian-Triassic mass extinction, life recovered twice as fast in the polar regions than elsewhere on Earth.
00:37:02How quickly can life recover after a global catastrophe?
00:37:09Answers may lie in the fossil record, at the top of the world.
00:37:14Scientists are looking at the world's biggest extinction event for clues about which species survived.
00:37:21When we're talking about an extinction in paleontology, it means total extinction.
00:37:27And it almost wiped the whole blackboard completely.
00:37:32It happened 252 million years ago.
00:37:36It was not only a regional disaster, but it was really the biggest disaster in Earth's history.
00:37:45And of course there were life on land, there were life in the ocean at that time, and most of it got extinct.
00:37:51About 252 million years ago, on the border between what we call the Permian and the Triassic time periods, the biggest volcanic eruptions in Earth's history happened.
00:38:10And an area was covered in Siberia that was between the size of India and Australia.
00:38:17And not only it was this big, but it was also thick.
00:38:21The thickness of this volcanic eruption, all the things that came up with the volcanoes, was about 2,000 meters if we average it.
00:38:29That's over one mile thick.
00:38:34Molten lava continued to spew for several million years.
00:38:38But it wasn't just the inferno that was deadly.
00:38:42The volcanics came in contact with evaporites.
00:38:46There had been a large sea in the area that completely dried out, like the Dead Sea today.
00:38:53So you have big salt layers.
00:38:55And of course, if you boil salt, you get a lot of nasty things.
00:39:01Because salt is a lot of chlorine.
00:39:04And when you start to boil chlorine, you get a gas.
00:39:07And that's really poisonous.
00:39:09And there's always some sulfur.
00:39:11And if you start to boil the sulfur stuff, you get poisons and you get acids.
00:39:19Sulfuric acids.
00:39:21Everything on land and in the sea was affected.
00:39:28Suddenly, we see in the rock layers, mud.
00:39:35Just dark gray mud.
00:39:38And we can start to dig in it and we can see that there's almost no life.
00:39:48It's just covered with dead mud.
00:39:52The dramatic end of the Permian is known as the Great Dying.
00:39:57And the ocean suffered the most.
00:40:00But something between 82 and 96% of all species in the ocean, everywhere, got extinct.
00:40:09Even hardy, iconic species, like trilobites, vanished forever.
00:40:15The disaster was so nearly complete that in most places it would take 10 million years for life to recover.
00:40:24The period that begins just after the Permian extinction, 252 million years ago, is known as the Mesozoic era.
00:40:34Through some wonderful work done by Chinese and English paleontologists for many years, they see that life slowly appears again.
00:40:43But the complex ecosystems that you see for the rest of the Mesozoic, they only appear after 10 million years.
00:40:52While Chinese and English paleontologists have calculated the recovery at 10 million years, Jorn and his team have searched the shale layers on Svalbard and found that recovery was much faster.
00:41:05We are down to at least half the time.
00:41:11For the scientists, this was a revelation.
00:41:15So in China, 10 million years.
00:41:17In Svalbard, 5 million years to a full ecosystem with top predators.
00:41:22We are trying now to push it down to 4 million years after the extinction.
00:41:27So then it's a 6 million year gap between a large ecosystem close to the equator and one on the northern end of the Pangaea.
00:41:36In Svalbard, we see that things are moving much faster back to a recovery.
00:41:41The scientists don't yet know why this is the case, but they're determined to solve the mystery.
00:41:46Jorn and his team are the first to document this transition in northern Pangaea, 5 million years earlier than researchers thought.
00:41:56It's an extremely fast evolution.
00:42:00We see the disaster taxa.
00:42:03We still see the bony fishes.
00:42:05Then we see the marine amphibians.
00:42:08But then we also have the first marine reptiles in the same layer.
00:42:14And this is something that's quite spectacular for us to see that actually we have the mix.
00:42:19We have the change.
00:42:21This is when we go from an environment that's just extremely strange because it's just after the big extinction into something that starts to hint towards a normal Mesozoic ecosystem.
00:42:36No matter how quickly life bounces back after pushing the reset button, it still takes millions of years before complete ecosystems thrive again.
00:42:45This has striking implications for Earth today.
00:42:49As we confront the climate crisis and increasing habitat destruction, we're seeing a pattern that parallels prehistory at warp speed.
00:42:58It's part of the impetus for scientists to decode the genomes of iconic extinct species and make plans to resurrect them within our lifetime.
00:43:08Thylacines once roamed throughout Australia.
00:43:11And a breakthrough in Melbourne may see them hunting in Tasmanian forests again soon.
00:43:17Andrew Pask is an expert in developmental genetics in Australia.
00:43:26His team made a huge breakthrough by sequencing the entire thylacine genome.
00:43:31But where did they get the thylacine DNA?
00:43:34Because people were going out and killing them on such a large scale, museums were really trying to collect specimens.
00:43:40They knew they were disappearing from the wild.
00:43:43And in some rare circumstances, there were females that were shot that still had babies in their pouch.
00:43:48And then those babies made it into museum collections.
00:43:51And that's what really enabled us to start looking into the biology of the thylacine.
00:43:57DNA from the Melbourne specimen had sequences long enough to recreate the entire 3 billion letter genome of the thylacine.
00:44:05But Pask and his team needed to isolate specific genes from the DNA strings for the next phase of their research.
00:44:14De-extinction and trying to bring an animal back to life is very different from animal cloning.
00:44:19Animal cloning is something we're very good at today.
00:44:22And that process, you have to start with a living cell.
00:44:25And you can put that living cell into an embryo.
00:44:28And you can use that living cell then to generate a whole other individual or clone of where that cell originally came from.
00:44:35The key thing for any of these sorts of technologies of bringing an animal back is you have to start with a living cell.
00:44:41So although we have the complete genetic blueprint of a thylacine, this is letters on a computer screen.
00:44:47This is not a living cell.
00:44:49There's a new technology called CRISPR-Cas9 technology.
00:44:54It's a DNA editing tool that we now have that enables you to make those edits.
00:45:00The number of edits that you have to make is in the order of millions of edits.
00:45:05The next step in Andrew Pask's journey through Jurassic Park Down Under will be to create a living thylacine genome by modifying the genome of a close living relative.
00:45:16We can start to think about surrogate species that we would use to genome edit to make them look like a thylacine.
00:45:24But the really big problem with the thylacine then would be transferring that embryo into another marsupial surrogate mother
00:45:31that would then have to give birth to a thylacine pouch young.
00:45:35Pask thinks that Western Australia's Numbat might provide the best starting DNA blueprint.
00:45:43It's one of the thylacine's closest living relatives, last sharing a common ancestor 30 million years ago.
00:45:51The termite-eating creature also has stripes.
00:45:55But adults are only slightly bigger than a squirrel, where adult thylacines were much bigger.
00:46:02Numbats are the closest living relative to the thylacine.
00:46:07But unfortunately these are insectivores, so they obviously have a very different digestive system.
00:46:14So they obviously have a huge amount of differences between their genomes.
00:46:18And that makes our job a lot harder because you would have to make many, many more of those edits to the blueprint
00:46:24to make our thylacine genome really come back to life.
00:46:29Why go to all this trouble to bring back an animal that's already extinct?
00:46:34It's one of the few animals that we know the exact moment that the last animal died
00:46:39and that species went completely extinct from our planet.
00:46:42And it's got this really sad story of extinction where we aggressively hunted this animal to extinction in the wild.
00:46:48The end goal of this de-extinction effort will be to reintroduce the thylacines to the wild reserves
00:46:55that cover about half of Tasmania today.
00:46:58With the thylacine it's really a great example of a species that you could just pop back into the ecosystem in Tasmania
00:47:05and it certainly has everything it needs there in order to not just survive but also thrive in that environment.
00:47:11Tremendous progress was made in 2019 in the fields of genetic and biomedical engineering.
00:47:19Science can now construct the facial features of suspects who leave DNA at the scene of their crimes.
00:47:27They're decoding what was formerly thought to be junk DNA to reveal more than 10,000 markers for facial recognition.
00:47:34Our DNA is key to so many aspects of our appearances and our health.
00:47:47Heart disease is the number one cause of death for our species worldwide.
00:47:51That's why researchers are trailblazing ways to repair hearts through gene manipulation to 3D printing.
00:47:59All around the world researchers are determined to learn how to fix a broken heart.
00:48:08Exploring multiple paths of inquiry to innovate new bioengineering methods.
00:48:15Even developing the technology to print a new heart.
00:48:20The process of healing occurs very slowly in the heart.
00:48:24It's believed that only 30% of its cells are replaced over 50 years.
00:48:34So once the heart is damaged, it takes a long time for recovery to take place.
00:48:41How can new heart cells be generated?
00:48:44It appears tiny extracellular bubbles called exosomes, some hidden within the heart, play a key role.
00:48:51They contain a message that can rebuild the heart.
00:48:58Renowned researcher Dr. Eduardo Marban tested this theory by giving with mice that had experienced cardiac infarction.
00:49:09The results were dramatic.
00:49:11This is the wall of the heart after cardiac infarction.
00:49:17The cells on the right side have died.
00:49:20And the wall has become thin.
00:49:23But in mice that received these additional messaging molecules,
00:49:29the number of cells had increased and the wall had become thicker.
00:49:33They might be very powerful agents in the treatment of disease in a way that defies all the conventions.
00:49:44Elsewhere, researchers investigate other approaches, including the development of lab cultured tissues and organs.
00:49:52This is Kenneth Chen, a world leading expert in the field of regenerative medicine.
00:50:03Here, the researcher adds a certain signaling molecule to an ES cell.
00:50:09It's called WNT.
00:50:11WNT.
00:50:12WNT molecules are present in large quantities in dividing eggs.
00:50:20After one week, part of the cell is starting to pulse.
00:50:24Two days later, large ripples move across the flattened cell.
00:50:47This is the very beginning of a human heart.
00:50:49You can take an embryonic stem cell that can become any cell and then instruct it to specifically, almost entirely, become human beating ventricular muscle.
00:51:05This is an exciting event.
00:51:09With the same transformative properties of embryonic stem cells, researchers in Israel are using iPS cells to develop startling new innovations.
00:51:19Even printing a miniature heart.
00:51:24This is the first time that the whole cellular heart with blood vessels is printed.
00:51:30How did they do it?
00:51:32Tal Devir and a team of research scientists at Tel Aviv University harvested patients' fatty tissue to produce a personalized biological hydrogel,
00:51:42as well as iPS cells, manipulated to become cardiac and vascular cells.
00:51:49Together, these form what Devir calls bio-inks.
00:51:54We have bio-inks for the heart and bio-inks for the blood vessels.
00:51:58And then we use a 3D printer to print whole hearts with the major blood vessels.
00:52:05The next stage is to mature these hearts in the lab for at least a month to help the cells or teach them how to interact with each other,
00:52:15how to provide electrical signal and to have a synchronous contraction or pumping ability of the heart.
00:52:22And in a year or two, we hope to take these hearts and transplant them in small animal models in rats or rabbits.
00:52:32Astounding, no doubt.
00:52:33Astounding, no doubt.
00:52:34And while much more work must be done to scale up the study, from printing rabbit-sized organs to a truly human-sized heart,
00:52:42its impact may be more immediate.
00:52:45And in a year or two, we hope to take these hearts and transplant them in small animal models in rats or rabbits.
00:52:54The jury's still out as to whether or not we should edit out dangerous genes in a way that would eliminate them entirely from all future generations.
00:53:03But living a full lifetime despite disease or serious injury seems to be the inherent goal of most species,
00:53:11whether human or animal, present or past.
00:53:14By studying both mortal and serious injuries on fossil bones,
00:53:18scientists in North and South America have redefined the daily lives of one of the most iconic prehistoric predators,
00:53:27Smilodon.
00:53:31Saber-toothed cats, it seems, are both fighters and lovers.
00:53:36Forget tigers, forget lions and leopards.
00:53:49One ferocious feline killed its prey with canines nearly a foot long.
00:53:55But while the beast weighed close to half a ton,
00:53:59walked on paws three times larger than a Bengal tiger's,
00:54:02Smilodon remains one of the most enigmatic predators, past or present.
00:54:14Now, scientists are breaking into Smilodon's secret life through those incredible things.
00:54:22So there's lots of advantages of having these elongated sabers,
00:54:26one of which is the ability to have your prey bleed out very quickly.
00:54:29Dr. Larissa DeSantis is a vertebrate paleontologist at Vanderbilt University.
00:54:36The sabre teeth are actually as long, if not longer, than some T-Rex teeth.
00:54:44Dr. Nicholas Schimento is at the Comparative Anatomy Lab of Vertebrate Evolution in the Natural History Museum, Buenos Aires.
00:54:53This is original material from a saber-toothed cat, a Smilodon Populator.
00:54:58It was found here, in Rio Areco, in the Pampas region.
00:55:03His new discovery in Argentina suggests that knife-tooth used its canines not just to dispatch prey,
00:55:08but to battle with members of its own kind.
00:55:16Here, it had an oval-shaped hole, and the shape coincided with the canine of a saber-toothed cat.
00:55:22So what we did was insert the canine into that hole, and it matched the shape and fit perfectly inside the skull.
00:55:36The punctures in both skulls could only have been inflicted by other Smilodons.
00:55:41So this is a wound that would have undoubtedly caused the animal to die.
00:55:49The Argentine specimen shows a wound that appears to be instantly fatal.
00:55:56It's a huge discovery, as Smilodon fossils are relatively rare in South America.
00:56:02Smilodon kittens didn't sport true fangs until they were about three years old.
00:56:07There is a true evolutionary benefit to having that tooth come completely in before the other tooth, the baby tooth, falls out.
00:56:18And that provides evidence that these animals were potentially provisioned or cared for because the teeth were so critical to their survival.
00:56:26Until their weaponry was fully developed, Smilodon kittens needed to stick close to mom.
00:56:32It was taking a long time for these teeth to develop, and those were that critical for hunting.
00:56:37Then there may have been an extended period of parental care, allowing for these animals to become more mature and able to hunt effectively on the landscape.
00:56:47This suggests that the prehistoric cats may have had expanded family structures, similar to wolves.
00:56:53We're not sure if saber-toothed cats hunted in pairs or in prides, but they worked together.
00:57:03The prehistoric landscape was rich with forests and prairies, with many big beasts.
00:57:16Giant ground sloths, short-faced bears, mammoths and mastodons, and camel-like creatures lived side by side with Smilodon.
00:57:25Saber-toothed cats were the apex predators throughout Pleistocene America.
00:57:33Still, hunting could be dangerous, and injury could make starvation for the predator.
00:57:38We can actually analyze the teeth of fossil animals and get an understanding of what they were eating.
00:57:48By analyzing the chemical signature of a Smilodon's tooth enamel, she can see what it preyed on and where that prey lived.
00:57:55And by studying the microscopic grooves and wear on the surface of the teeth, she can tell whether the owner crunched bone or dined on delicacies.
00:58:08What we actually found was pretty interesting is that the individuals that were injured were actually eating softer foods.
00:58:14And this suggests that potentially they were actually being provisioned foods.
00:58:19So these weren't animals that were sort of just desperately scavenging for whatever food they could find.
00:58:25They were actually able to get access to the flesh, likely, and potentially by other cats.
00:58:32And so that was really, really an exciting find.
00:58:36And that is quite remarkable, because that suggests that these animals were really, you know, caring for each other.
00:58:42Growing those saber teeth was a feat of evolutionary engineering that continues to fascinate everyone who lays eyes on them.
00:58:54Four little foot bones found by accident in 1994 have led South African scientists to discover the most complete paleoanthropological find of its kind.
00:59:04Since revealed, fossil by fossil, over 20 years, the new discovery replaces much guesswork with real answers about our early ancestors.
00:59:16She was an older woman, not much over four feet, and perhaps in her foraging, she'd been disturbed by something.
00:59:28Some predator, a saber tooth or a lion, and had hastily tried to get away.
00:59:34She fell into a cave, now known as the Sturckfontein, and the four little foot bones of hers were discovered here, quite by accident, 3.7 million years later.
00:59:46Usually, scientists only discover small fragments of a skeleton in the deep bedrock of time.
00:59:53These give them clues, but not many answers about our ancestors.
00:59:59That has all changed with little foot.
01:00:02I could see a little white bone that I recognized as a foot bone of a hominid, and then another one, and then another one.
01:00:15I also found part of a tibia, and I found part of a fibula.
01:00:21So I had parts of the foot and lower legs from left and right.
01:00:27From these first little foot fragments, the team, Ron Clark, Stephen Matsumi, and Nekwani Malefi, set out to find and piece together the rest.
01:00:38It was to be a labor of love over decades.
01:00:43Their biggest challenge was to remove soft fossil bone from breccia, a type of natural concrete, while keeping every single fossil fragment undamaged.
01:00:56These are the actual fossils, all assembled from one individual who fell into a cave 3.7 million years ago, and left us a legacy of knowledge beyond measure, including the only complete skull and complete dentition, Littlefoot.
01:01:16This was the first time ever that a complete adult skull of an Australopithecus had been found.
01:01:25It had arms that were like ours, relatively short, and I could see that the legs were actually longer than the arms, just like us.
01:01:37This human ancestor had proportions similar to us.
01:01:43The fossils which Littlefoot has offered up quite literally fill the missing gaps in our understanding of our early ancestors.
01:01:52Littlefoot, or Australopithecus Prometheus, stood upright and has waited a long time to pass on her secrets.
01:02:01And there's no doubt, she'll give us more answers in time to come.
01:02:07And now, archaeologists may have finally figured out how the pyramids were built.
01:02:12At the ancient quarry of Hotnup, they unearthed the contraption that would have been used to transport heavy alabaster stones up a very steep ramp, 4,500 years ago.
01:02:26At the foot of the pyramid of Khufu, we can still see the quarries from which the majority, that's about 95% of the blocks, were extracted.
01:02:36By building the pyramids, the ancient Egyptians transformed the landscape, changing the geography of the place.
01:02:43They literally tore off much of the rocky base of the Giza Plateau.
01:02:48The Sphinx itself is a remnant of this hard limestone plateau.
01:02:53And with all the gravel and excess stone this method produced, would have been reused to build the ramps.
01:03:03But what type of ramp did they use 4,500 years ago to transport blocks to a height of 146 meters?
01:03:10The debate is raging between Egyptologists and specialists, and many models have been proposed.
01:03:17A single ramp is either too steep or too long to maintain a realistic slope of no more than 12%.
01:03:24Several ramps seem to be a very costly solution in terms of time and effort.
01:03:31Is it an external wrap-around ramp?
01:03:36Or the kind of internal ramp proposed by architect Jean-Pierre Houdin in the 2000s?
01:03:46For now, there's no definitive evidence that would settle this debate.
01:03:50Again, it may be necessary to distance ourselves from the pyramids to find some answers.
01:03:56300 kilometers south of the Giza pyramids.
01:03:59A Franco-British archaeological mission, with the help of a hundred Egyptian workers,
01:04:03is possibly about to make a major discovery.
01:04:06In no other quarry have these types of elements been found.
01:04:13A ramp, at a 20 to 25% grade, and in some places even more, depending on the location.
01:04:21And on the sides, there are stairs, with holes cut into the rock.
01:04:40What were these holes used for?
01:04:44How did this ramp work?
01:04:46Can it provide new clues about the construction of the pyramids and the ramp system used at the time?
01:04:53Olivier Levine has analyzed all these clues and developed a hypothesis.
01:04:59So here, I have a poteau in front of me.
01:05:06The poteau in front of me is vertical, so the poteau was well installed here.
01:05:10A big poteau circulaire, you can imagine that.
01:05:12It's quite a consequence.
01:05:14So we have an installation here,
01:05:17which allows, when the big blocks come on the road of a halage,
01:05:21to have some teams who come and take the block,
01:05:24and others, with some cordages, who turn around the poteau here,
01:05:28who will descend and who will be able to, like that,
01:05:31to make up again the block.
01:05:33I will be able to take the cordage and take it,
01:05:36and descend to the bottom.
01:05:38And that's what will make up, in fact, the block.
01:05:43And I have another trou, here,
01:05:45which makes a jump of force,
01:05:47and here, in the height,
01:05:49to support the poteau,
01:05:50to prevent the poteau from the Nile.
01:05:53We need a tronc d'arbre,
01:05:56which is very lisse,
01:05:57which is very circular,
01:05:58so that the cordage can be well glissed.
01:06:00They would have used mud,
01:06:02silt from the Nile,
01:06:04to lubricate the ramp and slide the block,
01:06:06eliminating friction as much as possible.
01:06:09Here, along the towpath,
01:06:11large alabaster stones,
01:06:13possibly weighing as much as 58 tons,
01:06:16could be moved this way.
01:06:20So as the block advanced,
01:06:21the teams above would have positioned the ropes ahead of time,
01:06:24on the next set of poles,
01:06:26so that the block would have moved forward
01:06:28as smoothly as possible.
01:06:30According to Olivier Levine,
01:06:42this ramp system could have been adapted to the Pyramid of Khufu.
01:06:51But ramps on the pyramid were not built out of rock.
01:06:54Instead, they were constructed with gravel and bricks.
01:07:00So, to secure and stabilize the space between the poles,
01:07:05they used wooden crossbars inside the ramp,
01:07:09and also above it.
01:07:11But is this system feasible?
01:07:15This hypothesis needs to be tested under real conditions
01:07:18to know for sure.
01:07:30Is it possible to be tested by the way?
01:07:31As of the way,
01:07:33it's safe to ensure that the big goal of doing these movements
01:07:34is not entirely different.
01:07:35It's so fun,
01:07:36that the people whoæ© down the road
01:07:37is not necessarily"!
01:07:39So far,
01:07:40the bisher of the track is not necessary.
01:07:42I think that's something as possible.
01:07:43In a way,
01:07:44the world has changed the way to be tested.
01:07:45It's a natural way
01:07:46to go.
01:07:47I think can be preserved.
01:07:48It's a natural way to make
01:07:49this space for arsehole.
01:07:51But the past the future will have been made
01:07:52to make this round.
01:07:53I think it's fun
01:07:54to make this!
01:07:55There's a natural way to learn
01:07:56to live with the people
01:07:57that have moved on.
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