If engineers start up a hypersonic engine at the University of Central Florida (UCF) and you’re not around to hear it, does it make a sound?

Hypersonic travel is anything that travels by at least 5x more than the speed of sound. A team of aerospace engineers at UCF have created the first stable hypersonic engine, and it can have you travelling across the world at 13,000 miles per hour!

Compared to the 575 mph a typical jet flies, commercial hypersonic travel is a first-class trade-off anybody would be willing to make.

In fact, a flight from Tampa, FL to California would take nearly 5 hours on a typical commercial jet; whereas, with a commercial hypersonic aircraft, it will only take 10 minutes.

So here’s the question: When can we expect commercial hypersonic air flights?

When we stop combusting engines and start detonating them! With a little background information, you’ll be shocked to know why.

Challenges and Limitations of Commercial Hypersonic Travel

The challenge with commercial hypersonic air travel is that maintaining combustion to keep the movement of an aircraft going in a stable way becomes difficult. The difficulty comes from both the combustion and aerodynamics that happens in such high speeds.

What Engineering Challenges Arise in Controlling and Stabilizing Hypersonic Aircraft at Such High Speeds?

Combustion is the process of burning fuel. It happens when fuel mixes with air, creating a reaction that releases energy in the form of heat. This mixture of air and fuel create combustion, and combustion is what generates the thrust needed for the movement of most vehicles.

But hypersonic vehicles are quite different. A combustion engine is not very efficient for vehicles to achieve stable hypersonic speeds. For a hypersonic aircraft to fly commercially, a detonation engine is needed.

Detonation can thrust vehicles into much higher speeds than combustion, so creating a detonation engine is important for commercial hypersonic air travel. Detonation engines were thought of as impossible for a very long time, not because you couldn’t create them, but because stabilizing them is difficult.

On one hand, detonation can greatly speed up a vehicle or aircraft, but on the other hand, both the power and the speed it creates makes stabilizing the engine even harder.

How Do Aerodynamic Forces Impact the Design and Operation of Hypersonic Vehicles?

Aerodynamics relates to the motion of air around an object—in this case, an aircraft. As you can imagine, friction between an aircraft and the air it travels through generates a tremendous amount of heat. The faster the vehicle, the more heat created.

Commercial hypersonic vehicles must be able to manage the heat created at hypersonic speeds to keep from being damaged altogether.

Hypersonic aircraft do exist, but only in experimental forms such as in military application. NASA’s Hyper-X program develops some of these vehicles, one of which is the X-43A which could handle hypersonic speeds of Mach 6.8 (6.8x faster than the speed of sound).

Mach Number Range	Name
1.0 Mach	Sonic	Exactly the seed of sound.
1.2-5 Mach	Supersonic	Faster than the speed of sound, characterized by shock waves.
>5.0	Hypersonic	More than 5x speed of sound, with extreme aerodynamic heating.

But vehicles for commercial hypersonic air travel is still a work in progress

Engineers say that we will have these vehicles by 2050, but it may even be sooner that that. Here’s why.

Future Prospects and Developments in Hypersonic Travel

The worlds first stable hypersonic engine was created back in 2020 by a team of aerospace engineers at UCF, and they have continued to refine the technology since. This work is revolutionizing hypersonic technology in a way that had been thought of as impossible just a few years ago.

To create a stable engine for commercial hypersonic air travel, an engine must first be created that can handle detonation, but not only that, this engine must actually create more detonations while controlling.

This is because in order to achieve hypersonic speeds and then keep it at that level, there needs to be repeated detonations thrusting the vehicle forward.

The development at UCF did just that. They created a Rotating Detonation Engine (RDE) called the HyperReact.

What Technological Advancements are Driving the Development of Commercial Hypersonic Travel?

When combustion happens, a large amount of energy creates a high-pressure wave known as a shockwave. This compression creates higher pressure and temperatures which inject fuel into the air stream. This mixture of air and fuel create combustion, and combustion is what generates the thrust needed for a vehicles movement.

Rotating Detonation Engines (RDEs) are quite different. The shockwave generated from the detonation are carried to the “test” section of the HyperReact where the wave repeatedly triggers detonations faster than the speed of sound (picture Wile E. Coyote lighting up his rocket to catch up to Road Runner).

Theoretically, this engine can allow for hypersonic air travel at speeds of up to 17 Mach (17x the speed of sound).

Hypersonic technology with the development of the Rotating Detonating Engine will pave the way for commercial hypersonic air travel. But even before that happens, RED engines will be used for space launches and eventually space exploration.

NASA has already begun testing 3D-printed Rotating Detonating Rocket Engines (RDRE) in 2024.

How Soon Can We Expect Commercial Hypersonic Travel to Become a Reality?

Since we now have the worlds first stable hypersonic engine, the worlds first commercial hypersonic flight won’t be far off. Professor Kareem Ahmed, UCF professor and team lead of the experimental HyperReact prototype, say’s its very likely we will have commercial hypersonic travel by 2050.

Its important to note that hypersonic air flight has happened before, but only in experimental form. NASA’s X-43A aircraft flew for nearly 8,000 miles at Mach 10 levels. The difference is that the X-43A flew on scramjets and not Rotating Detonation Engines (RDEs).

Scramjets are combustion engines also capable of hypersonic speeds but, which are less efficient than Rotating Detonation Engines (RDEs) because they rely on combustion, not continuous detonation.

This makes RDE’s the better choice for commercial hypersonic travel, and it explains why NASA has been testing them for space launches.

One thing is certain:

We can shoot for the stars but that shot needs to be made here on Earth… If we can land on the moon, we’ll probably have commercial hypersonic travel soon.

A Great Advancement for 3D Printed Organs

3D printing in hospitals is nothing new, but for the first time in history, a woman received a 3D printed windpipe that became a fully functional without the need for immunosuppressants.

Immunosuppressants are used during organ transplants to keep the body from attacking the organ that it see’s as foreign. This means that the organ the woman received was organic and personalized for her, as if she had it her entire life.

This mind-blowing news shows that we are now closer than ever to being able to create full-scale, functional, and complicated 3D printed organs like a heart or lung.

But what about creating a brain?

3D Printing and Organoid Intelligence

Organoid Intelligence, or OI, is an emerging field of study that is focused on creating bio-computers by merging AI with real brain cells called organoids. Organoids are miniature and simplified versions of organs grown in a lab dish. They mimic some of the functions of fully grown organs, like brains. The idea behind OI is that by increase the cells organoids contain, they may begin to function like fully grown brains, and can then be used alongside computers to enhance Artificial Intelligence.

It turns out that the world’s first 3D printed windpipe was so successful that we are now closer than ever to creating the world first organoid intelligent bio-computer.

Here’s why.

The World’s First 3D Printed Windpipe

Transplant patients usually have to take a long course of immunosuppressants that help the body accept the organ. The body see’s the organ as foreign, and so the immune system begins to attack the new organ, which can lead to more complicated health problems.

The woman in her 50’s who received the 3D printed windpipe did so without any immunosuppressants. In just 6 months after the operation, the windpipe healed and began to form blood vessels, and of course, more cells.

The current goal of scientists in the field of Organoid Intelligence is to increase organoids from 100,000 cells to 10 million, and this begs the question:

Can 3D printing help build bio-computers by creating better organoids?

Can 3D Printing Help Build Bio-Computers?

The worlds first 3D printed windpipe shows that advances in 3D printing can create better functioning organs, and this implies that we can also create more intricate organoids to help in the field of Organoid Intelligence and eventually create bio-computers.

Its important to understand the distinction between 3D printing an organ and printing something like a tool or musical instrument.

The difference between printing an organ and printing a non-biological structure depends on the ink being used in the 3D printer.

3D printing non-organic structures will require ink that can be made from plastic, plastic alternatives like PLA, metal, and ceramics. On the other hand, 3D printed organs are made from ink called “bio-inks” that are a mixture of living cells and biocompatible substances like the ones mentioned above.

In the case of the 3D printed windpipe, the ink used was partly formed from the stem and cartilage cells collected from the woman’s own nose and ear. It was because of this bio-ink that the woman’s body did not reject the organ.

The Problem With 3D Printed Organs

Organs created with bioprinting need to function like real organs for the body to safely use them, and this does not happen right away.

The 3D printed organs need to go beyond just a printed structure and become living. They need to form tissues and cells that help create biological functionality, and forming these cells take time.

The problem with 3D bioprinting is that the ink used for the printer needs to be effective at doing this, and if it is not, the organ may not stay functional.

The ink used for the 3D-printed windpipe was made from part bio-ink and part polycaprolactone (PCL), a synthetic polyester material.

PCL is a used in the 3D ink for the purposes of maintain the structure of the windpipe, while the bio-ink is used to help the 3D printed organ to become fully biological in time so that the body can use it.

The PCL maintains the structure while the bio-ink does it’s thing.

The problem with PCL is that it is biodegradable and won’t last forever. In fact, doctors don’t expect the 3D-printed windpipe to last more than five years.

The Solution is Better Bio-ink

The 3D printed windpipe was not just made using PCL, but it contained bio-ink made from living cells too. The hope is that the living cells in the 3D printed organ—which came from the bio-ink—will assist the patient’s body in creating a fully functional windpipe to replace the PCL’s function.

If the organ begins to form cells and tissue by itself, then the function of PCL will be replaced by the biological function of the organ that is growing.

The organ becomes real!

Bio-Ink helps the 3D printed organ mimic it’s natural environment of cells and eventually become a real organ.

3D Printing Organs Will Save Lives

Every year, thousands of people need a lifesaving organ transplant. These transplants cost hundreds of thousand of dollars, and many people who need them don’t make it passed the waiting list.

3D Printing organs could give people the incredible opportunity to receive the help they need when they need it, saving thousands of lives annually, and millions of lives in the long run.

As advances are made in 3D Bioprinting, they will also be made in areas of Organoid and Artificial Intelligence, which shows that the progress being made in one place will once again shine its way to another.

The Extinction Problem

The diversity of the species on this planet is standing at a history-breaking climax that has never been equaled. More species are disappearing than ever before in recorded history. In the last 500 years alone, 869 species have been driven to extinction by human beings. Right now, as many as 16,928 species of plants and animals are known to be threatened with extinction.

The De-extinction Solution

Yet, at the same time, thanks to recent scientific advances in genetic engineering, we might be able to bring back once extinct species.

One company, Colossal Biosciences is doing just that with what can be called a potential “de-extinction solution”. They say they are getting closer to bringing back the dodo Bird, the Thylacine, and even the Woolly Mammoth.

These were a keystone species, and Colossal Biosciences says that using genetic engineering to bring them back could restore entire ecosystems.

What is Colossal Biosciences?

Colossal Biosciences is a biotechnology and genetic engineering company that is focused on de-extinction projects to bring back extinct species. Many extinct species have had a beneficial impact on ecosystems. Colossal claims that bringing them back could greatly help the Earth by curbing extinction and helping strengthen ecosystems.

According to their website, “Through technological and engineering breakthroughs in biosciences and genetics, Colossal is accepting humanity’s duty to restore Earth to a healthier state, while also solving for the future economies and biological necessities of the human condition.”

According to Business Wire, Colossal Biosciences has raised $225 million in funding to put towards their efforts.

Who Founded Colossal Biosciences

Colossal Biosciences was founded by Scientist Dr. George Church and entrepreneur Ben Lamm.

Dr. George Church is a leading scientist in synthetic biology at Harvard University. He is best known for developing the first genomic sequencing method and helping initiate the Human Genome Project—an undertaking to study and map human DNA.

Ben Lamm is a dynamic entrepreneur who has served as CEO of multiple companies that focused on everything from AI in space to marketing and video games.

When Was Colossal Biosciences Founded?

Colossal Biosciences officially opened its doors in 2021 after Dr. George Church and Ben Lamm started discussing the possibility of a de-extinction project.

Two years prior, Dr. Church and Ben Lamm got together for the first time. At that time, Lamm had been the CEO of another company he had founded called Hypergiant. This company’s focus was on aerospace and the military. As part of his work there, he’d been working on a small device that develops algae that can clean as much air as an acre of trees.

It was during this conversation that Dr. Church and Ben started discussing a colossal undertaking.

Where is Colossal Biosciences Located?

Colossal Biosciences has four main locations: Melbourne, Boston, Massachusetts, and Dallas. The company has a lab in Harvard University and another across the globe at the University of Melbourne in Australia.

The Colossal De-extinction Project

De-extinction is a process of creating a hybrid animal using genes from an animal that is similar to the extinct one. The traits these animals display are similar to the extinct species, and are specifically selected by scientists.

In other words, a de-extinct animal will be neither the living species nor the lost one. It will be a scientifically designed combination of the two.

This is a pretty startling thing to think about. It could be incredible to see something like a Woolly Mammoth walking around.

However, Colossal Biosciences has a much more profound reason for their huge undertaking.

Why De-Extinction?

Colossal Biosciences is using de-extinction to fill gaps in ecosystems long vacated by lost species to heal the world.

Every species plays a distinct role in its ecosystem. The natural world is very intertwined in a never-ending series of food chains and cycles. Everything impacts everything else.

When a species is removed from its environment, the impact can be very profound. So much so that people are creating shoes that help play the role that many of these important species fill—like the rewilding shoes.

Plants and animals that relied on the lost species can experience many problems. Overpopulation, a decrease in numbers, or even extinction can result from the loss. The quality of soil, air, and water can be impacted and even downgraded.

Colossal Biosciences believes they can reverse the damage. All they have to do is reintroduce these lost creatures to the ecosystems they left behind. The right animals can restart processes and habits long neglected. Habitats can be returned to an earlier and healthier state, and entire ecosystems formed.

The Process of De-extinction

De-extinction has made some real progress, but some challenges still remain. This makes de-extinction mostly conceptual. Regardless, the process of de-extinction is something that can be broken down into steps.

• Finding Well-Preserved Specimens of the Extinct Animal: The longer a species has been dead, the more degraded its DNA. Frozen tundra and museum samples are often the best sources of DNA for many animals.
• Sequence the Genes from the Extinct Species: Scientists use gene sequencing to compare the DNA of an extinct species to its closest living relative. This identifies the key differences that need to be altered to potentially bring the extinct animal back.
• Find the Closest Living Relative and Sequence its Genes: The genes of the lost animals are then combined with those of a living species to create offspring.
• Gene Editing: Once both sets of DNA have been sequenced, they must be combined or edited. Scientists will take the traits they need from the extinct species and insert them into the DNA of the living species. They will handpick the traits they need in order for the species to help regenerate the ecosystem.
• Create the Embryos: In the case of a mammal, the nucleus containing the DNA will be inserted into the egg, or ova. The egg will then be united with a sperm and implanted into the surrogate mother’s womb. For the bird, edited DNA will be injected directly into the surrogate mother so it can be transferred into the eggs that she lays.
• Birth or Hatching: The surrogate mother will be cared for until the baby is born, or the egg is laid and hatched. What emerges will be an animal that looks and behaves like its ancestors, but which is actually a combination of the extinct and the living species. It will contain all the traits necessary to replenish the earth.

The animals selected for De-extinction by Colossal Biosciences are the Woolly Mammoth, the Thylacine, and the Dodo Bird.

Colossal Woolly Mammoth

Height	6 to 12 Feet
Weight	Up to 6 tons
Extinction Date	Approximately 4000 years ago
Appearance	Resembles elephant with smaller ears. Two layers of fur, humpback, long truck, and stocky build.

There are a few good reasons that Colossal Biosciences has chosen the Woolly Mammoth as one of its first projects.

Woolly Mammoths frozen in the Siberian tundra have often been so well-preserved that they almost looked like they were ready to get up and walk away. For this long gone species, surviving DNA is plentiful.

They also have a living relative that is already their exact clone. The Asian elephant’s DNA sequence is a 99.6% match to that of the Woolly Mammoth. That remaining 4% is still a pretty big hurdle for the scientists at Colossal Biosciences. However, the huge percentage still in place puts them way ahead of the game.

Why Bring Back the Woolly Mammoth?

The Woolly Mammoth lived in an ancient ecosystem called the Mammoth Steppe. Nearly 1600 billion metric tons of carbon are stored in the permafrost that comprises what’s left of the Steppe. Bringing back the Woolly Mammoth would bring back the Steppe, and this could help reduce global warming.

The Mammoth kept these ecosystems alive by trampling down bushes and pushing back trees. They also fertilized the grass with their droppings.

Colossal Biosciences lists 10 goals they expect will be achieved by bringing back the Woolly Mammoth.

·       Slow down the melting of the permafrost.

·       Prevent the escape of carbon trapped in the permafrost.

·       Restore the lost grasslands of the Mammoth Steppe.

·       Restore the Mammoth Steppe to its former, healthier condition.

·       Return the Mammoth Steppe to an ecosystem to defend the Earth against climate change.

·       Better understand the genetic traits of cold-resistant animals.

·       Save modern elephants from extinction.

·       Prove a link between genetics and climate change.

·       Equip Nature to resist the damaging impact of human activity.

·       Drive advancements in genetic editing.

Final Result: The Mammophant

The resulting hybrid creature is already being called a Mammophant. It will be part elephant, but it will also have the traits that made the mammoth the king of the frozen tundra. This will include the thick fur and extra layers of fat tissue.

It will also be big and powerful enough to carry on the work the mammoths left behind. This includes clearing the grasslands and, hopefully, returning them to their original healthy state. The grasslands, in turn, should provide a much-needed opportunity to manage the global warming problem.

Colossal Thylacine:

The Thylacine is an animal of many names. It has been known also as a Tasmanian Wolf or a Tasmanian Tiger, although it’s neither canine nor feline. It’s a marsupial that once lived on Tasmania, an Island off the Southern Coast of Australia.

Height	20” to 27”
Weight	35 to 65 lbs.
Date of Extinction	1936
General Appearance	looks like a cross between a coyote and a tiger. Brown with stripes. Narrow, pointed face and long tail.

How did the Thylacine Go Extinct?

Their story is a tragic one. Through exaggeration and wild tales, the Thylacine developed a reputation for being a fierce predator. It was mistakenly regarded as a huge threat to local sheep farmers on the Island. None of this was true. They mostly ate rodents, lizards, and birds.

The Islanders became determined to defend themselves against this falsely accused menace. At one time, the government even offered a bounty of one pound for each Thylacine killed. Farmers and hunters were more than happy to collect.

The last thylacine died in a zoo in 1936 having lived its last years in solitude and neglect.

Why Bring Back the Thylacine?

The Thylacine was an apex species. This means it was at the top of the food chain in its ecosystem. It played a key role in keeping the populations of other species balanced. When the thylacine went extinct, every animal beneath it on the food chain was impacted, which created a cascading effect called trophic downgrading. Scientists at Colossal Biosciences believe that a reintroduced the Thylacine can end trophic downgrading. Tropic downgrading causes a variety of negative consequence:

·       Increased occurrences of devastating diseases.

·       Increase in the number of wildfires.

·       Decrease in the amount of carbon stored.

·       Introduction of more potentially damaging invasive species.

·       Interruption of the cycles which distribute chemicals and compounds throughout the ecosystem.

Of the three species being brought back first, the Thylacine is the one that’s been gone for the least amount of time. Plenty of embryos and young Thylacines were preserved before they disappeared. So, there’s plenty of intact DNA at hand.

The closest living relative to the Thylacine is a little mouse-like critter called the Fat-Tailed Dunnart. Its DNA is 95% identical to that of the Thylacine. This animal has a strong population and a conservation status of “least concern”. That means there are plenty of specimens and a large supply of living DNA for Colossal Biosciences to work with.

Final Result: The Thylanart

This hybrid doesn’t have an official name, yet. In the tradition of mixing parental names, it could be called a “Thylanart”. This animal, although it will be made from a creature the size of a mouse, will still grow to be as big as a small dog. It will also bear the traits that allowed its ancestor to be an apex animal and can rebalance the Tasmanian ecosystem to its former, natural state.

Colossal: Dodo Bird

The dodo, the only bird in Colossal Biosciences’ initial species index, is something of an iconic symbol for extinct species. It was a large, flightless bird that lived on tiny Mauritius Island which lies off the east coast of Madagascar, the famous Island of Africa.

Height	32” to 38”
Weight	20 to 50 lbs.
Date of Extinction	Approximately 1662 – 1690
Appearance	Thick, curved beak. Course, brownish-gray feathers, and feet.

How did the Dodo Bird Go Extinct?

When humans started to colonize Mauritius Island in the 1500s, the dodo’s future changed forever. Settlers brought with them new species of animals such as rats, pigs, goats, deer, and birds. These creatures threatened the supply of naturally existing plant species, and they developed a taste for Dodo bird eggs. This is not good news for a bird that only lays eggs once a year.

One of the most devastating problems the dodo faced, however, came in the form of hunting rifles. Local settlers developed a liking for dodo bird meat and, fast as the dodo was, it couldn’t outrun a bullet.

Why Bring Back the Dodo Bird?

“Almost a third of Mauritius’ native fruits are no longer being dispersed as no animals are big enough to swallow their seeds.”

These startling words from the Natural History Museum’s website encompass the pressing need many scientists have to bring back the dodo bird. The loss of the dodo and other species is bringing this tropical ecosystem to its knees. Little by little, it’s disappearing simply because of the lack of a Dodo bird.

Final Result: The Docobar

This hybrid bird could be called a “Docobar” because of the mixture of dodo bird and Nicobar Pigeon DNA that it will have. The Nicobar pigeon, a brightly colored bird from India, is the Dodo bird’s closest living relative.

Colossal Biosciences aims to design the Hybrid to thrive on the dodo bird’s old stomping grounds, Mauritius Island. More than that, it should resume the activities of its ancestors such as swallowing and fertilizing seeds.

When Will the Animals Become De-extinct?

How long until the world can expect to see “Mammophants” thundering across the Arctic or to watch the first “Docobar” push its way out of its shell?

Of course, Colossal Biosciences can’t provide a precise birthdate for the world’s first resurrected hybrid animals. However, they’ve given their best estimates.

Woolly Mammoth – 2027-2028: Colossal is pushing hard for the Woolly Mammoth Hybrid to be the first revived. In early 2023, Colossal Biosciences raised an additional $60 million in funding specifically for this project.

Thylacine – 2028: Scientists believe the Hybrid Thylacine won’t be far behind the Woolly Mammoth. They’ve given it a projected birth date of as early as 2028. Marsupials have a much faster gestation rate than most other mammals. This could mean we see them sooner than the Mammoth.

Dodo Bird – Unknown: The dodo bird’s revival is very complicated and challenging due to a lower selection of viable DNA samples. As well, their closest living relative isn’t a closely related as scientists would like. Although new techniques are being developed, it’s not known when there might be a fertilized egg.

De-extinction is becoming a more popular topic of conversation, especially with Colossal Biosciences gaining popularity. It’s a new and strange idea once only possible in the realm of fantasy, and the world is still trying to make sense of it. It could be the miracle the environment needs, or it could be a big mistake.

The Pros of De-Extinction:

There are plenty of arguments as to why de-extinction could be a welcome new phase in our natural history.

• Knowledge: Continued work on the de-extinction project brings new knowledge of DNA and genetics. This new understanding could help us in ways we can’t imagine.
• Environmental Health: The resurrected animals could help us bring the planet back to a state of health not seen in a long time.
• Justice: Humans created the mess that the planet currently finds itself in. It’s only fair and right that humans figure out how to fix it.
• Curiosity: There’s just a certain awe that comes with the prospect of seeing a species never before seen alive.

The Cons of De-Extinction:

At the same time, there are lots of reasons for scientists to proceed with plenty of caution. Colossal biosciences will have to consider the following:

• Animal Rights: The simple fact is, that animals can’t tell us if this is something they want or not. Injury or illness could be caused by inevitable trials and errors.
• Viruses: There is a risk that resurrected genes could also bring back viruses and diseases the world is not prepared for.
• Environmental Health: Scientists can’t be 100% sure how these hybrids will impact the ecosystems they inhabit.
• Political Focus: The introduction of de-extinct species could take attention and resources away from other issues. Current endangered species could be neglected.

The biggest question being asked, however, and the one that needs the most attention is the question of ethics.

The Ethical Debate About De-Extinction:

With all the talk of de-extinction, many people are reminded of a movie that came out in the 1990s. It involved de-extinct dinosaurs running around a tropical Island terrorizing scientists and children.

Over and over again, a thought from that movie has been resurfacing. In a nutshell, we know we can do it. The question is whether we should do it.

A big concern is that, if de-extinction became a reality, people might think there is now an infinite supply of any given species. They might become lax about conserving and protecting wildlife. Money that could be used to solve world hunger or clean up plastics pollution might, instead, go into the next hybrid animal.

Paul and Anne Erlich from the Yale School of the Environment argue in their publication that de-extinction projects— like the one Colossal Biosciences is undertaking—are a terrible idea. If scientists don’t first address problems like destructive mining practices or creating a clean energy future, questions of de-extinction won’t even matter.

The environments these extinct animals left behind have changed vastly while they’ve been away. It’s not even certain that they could survive in the world that exists today.