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How have bees domesticated viruses?

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How have bees domesticated viruses? Some insects have turned wild viruses into tiny bioweapons to protect and nurture their young.

How have bees domesticated viruses?

If you pierce the ovary of a species of honeyless bee called Microplitis demolitor, many viruses will come out and shine like iridescent blue toothpaste. This parasitic bee lays its eggs inside the cocoon worm, and the particles in their ovaries are domesticated viruses that have been adjusted to remain harmless in the bees’ bodies and serve their purposes.

The virus particles enter the cocoon worm through the bee sting along with the bee’s own eggs. The viruses then empty their contents into the cocoon’s cells and deliver genes that differ from those of normal viruses. These genes suppress the cocoon’s immune system and control its growth, making it a safe breeding ground for baby bees.

The insect world is full of parasitic wasp species that spend their infancy eating other living insects. For reasons that scientists do not fully understand, bees have repeatedly tamed disease-causing viruses and turned them into biological weapons. Currently, many examples of this have been described and new research has pointed to more examples. Nowadays, researchers are discovering the mechanism of this process by studying viruses in different stages of domestication.

Bee reproductive organs
The blue color of these reproductive organs of bees comes from the high number of viral particles. Microplitis demolitor bees produce domesticated virus particles in their ovaries (pictured above). Diachasmimorpha longicaudata bees may be in the early stages of domesticating a virus from the poxvirus family that replicates in their venom glands (bottom image).

A prominent example of a virus domesticated by honey bees includes a group called bracoviruses, which are thought to be derived from a virus that infected the honey bee or its host, the cocoon worm, about a hundred million years ago. That ancient virus inserted its DNA into the honey bee genome. Since then, this DNA has become part of the bee’s genome and passed on to subsequent generations.

Over time, bees diversified into new species and viruses diversified along with them. Bracoviruses are found in about 50,000 honeyless bee species, including M. demalitor. Other domesticated viruses originated from different wild viruses that entered the bee genome at different times.

Parasitic bees spend their infancy eating other living insects

Researchers are debating whether domesticated viruses should be called viruses at all. In an article published in 2020 in the Annual Review of Entomology, an ecologist from the University of Wageningen in the Netherlands, Marcel Dick, explains how domesticated viruses indirectly affect plants and other organisms. He says some people say they’re still viruses, others say they’ve merged with the bee and are therefore part of the bee.

As the bee-virus combination evolves, the virus genome spreads throughout the bee’s DNA. Some genes are lost, but a certain set of them remain that are essential for making the initial infectious virus particles. These pieces are located in different places in the bee genome, but they can still communicate with each other. “They’re still making products that work together to make virus particles,” says University of Georgia entomologist Michael Strand. “But instead of having a complete viral genome like the wild virus, the domesticated virus particles act as a delivery vehicle for the bee’s weapons.”

The weapons that bees use are very different. Some of them are proteins, while others are genes on small pieces of DNA. Most of them bear little resemblance to what is seen in bees or viruses, so it is not clear where they originated. They are also constantly changing and are in an evolutionary arms race with cocoon defenses or other measures.

In many cases, researchers have yet to discover what the genes and proteins do inside the bee host or prove that they function as weapons. But they have discovered some details. For example, M. demolitor bees use bracoviruses to deliver a gene called glc1.8 to the immune cells of moth larvae, which causes the infected immune cells to produce mucus that prevents them from attaching to the bees’ eggs. Other genes in M. demolitor bee bracoviruses cause immune cells to destroy themselves, while others prevent larvae from suffocating the parasite in melanin sheaths.

Bees maintain their control over viruses

Taming viruses can be dangerous. However, the wild relatives of domesticated viruses can be lethal, causing cells to produce virus particles and then burst them to release their contents. Some of them cause the body of insects to dissolve and turn them into sticky juice. In fact, even under domesticated conditions, sometimes specialized cells inside bees’ ovaries must burst to release viral particles. The bee must find a way to control that virus so that it does not infect and destroy the bee itself.

Parasitic bee larvaeCotesia glomerata wasps lay their eggs along with barcovirus particles in white butterfly larvae. Bracoviruses infect the cells of the cocooning worm so that the worm’s body cannot harm the developing bees. When the bee larva is ready, it leaves the cocoon and turns into a pupa. The cocoon worm makes a protective web over the bee pupa and protects them until they mature. The virus remains in the cocoon’s cells until the bee larvae emerge, so some researchers speculate that they may be responsible for the cocoon’s protective behavior.

How did bees evolve to be able to domesticate bees? More importantly, they have neutralized viruses. Virus particles cannot reproduce because they do not contain the genes that are critical for making new virus particles. They remain in the bee genome.

Bees also control where and when domesticated virus particles are produced. The reason for this is probably to reduce the risk of recalcitrance of the virus. Bracovirus particles are made only in one part of the female reproductive system and only for a limited time, and the key genes of the virus have been completely destroyed so that domesticated viruses cannot replicate their DNA. This loss is seen even in recently domesticated viruses, suggesting that this step is critical.

Any gene that is not useful for the bee gradually accumulates mutations. In bracoviruses, so much time has passed that unused genes are detectable. In recently domesticated viruses, residues are still detectable.

Discovery of mechanisms

It is not unusual to have a genome full of dead viruses. Viruses always jump into animal genomes. Even our DNA is full of remnants of viruses. However, only parasitic bees are known to have the ability to maintain a complete set of genes that work together to make viral particles.

Virus particles within the bee genome do not replicate because they do not contain the genes that are critical for making new virus particles.

Researchers are eager to understand how these relationships begin. For clues, some have turned to the tiny orange honey bee Diachasmimorpha longicaudata , which may be a poxvirus in the early stages of domestication. This poxvirus is not a true domesticated virus because its DNA was not introduced into the bee genome. Instead, the virus replicates inside the bee’s venom glands.

Like other virus-harvesting bees, the D. longicaudata bee injects virus particles into its host, which in this case is a fruit fly larva. Kaufman and Burke, along with Taylor Harrell, have shown that without poxviruses, most bee larvae die. But unlike fully domesticated viruses, this poxvirus replicates outside the bee and produces new virus particles in larval cells. The bee takes advantage of the poxvirus but does not completely control it.

Kelsey Kaufman, an entomologist at the University of Tennessee, says this poor control could be an indication of the type of virus the bees are starting with. Most domesticated viruses originate from a type of virus called nodiviruses, which can integrate into the bee genome more easily than poxviruses. But it is also possible that the bees have not had enough time yet. In fact, the association between bees and poxviruses is so new that it appears to exist in only one species of bee.

The virus is only found in certain tissues and only reproduces when the eggs are developing, which could mean that the bee has already developed defenses. Viruses also seem to be losing their ability to transmit without the help of bees. Kaufman has tried feeding flies many viruses and they didn’t seem to get infected that way.

parasitic beeDiachasmimorpha longicaudata wasps dig their stingers into the web to reach their host, the larva on that side. When they inject their eggs, they also introduce a type of poxvirus with the eggs into the larvae, which may be in the early stages of domestication.

Kaufman calls the poxvirus system exciting because little is known about how the domestication process of viruses begins. We cannot go back and see how this process begins. However, the new system can provide us with an insight into the beginning of this process. Although no one knows for sure why parasitic bees continue to domesticate viruses, researchers speculate that it has something to do with their lifestyle.

Internal parasites live inside their hosts, which are dangerous environments that they actively try to kill. From the bee’s point of view, viruses are like packages full of tools to solve this most catastrophic problem.

A study published in 2023 supports this idea. This research examined the genome of more than 120 species of honey bees, ants, and honey bees. The researchers examined these genomes for signs of the types of viruses that are susceptible to domestication. They inferred the presence of domesticated viruses by identifying viral genes that were functionally conserved over evolutionary time. Such conservation is expected if the genes help bees to survive or reproduce.

As expected, non-parasitic insects showed little evidence of having these domesticated viruses. The same was true for parasites that grow outside their hosts’ bodies where the host’s immune system cannot attack them. But in parasites that grow inside other insects, domesticated viruses seem to be much more common.

Julien Varaldi, a biologist at Claude Bernard Lyon 1 University in France and one of the authors of the study, says that there is a special connection between viruses and these internal parasites. This shows that viruses play an important role in the evolution of this lifestyle. With hundreds of thousands of bee species and countless strains of viruses, it’s highly likely that the two creatures could mate. In this situation, there are many opportunities for development.

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Do animals have an understanding of the concept of death?

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Some believe that animals may have a rudimentary understanding of death, but others think that humans are the only creatures that understand the concept of death.

Do animals have an understanding of the concept of death?

A chimpanzee named Muni had just been brought to a zoo in the Netherlands when she lost her child. The zookeepers did not know that she was pregnant. Zoe Goldsborough, a student who spent months studying and recording social interaction among chimpanzees, did not know this either.

One cold winter morning, Goldsborough saw Mooney sitting alone on a tree trunk in the center of the compound, holding something in her arms. It wasn’t unusual for Muni to be alone, as she had trouble bonding with the zoo’s 14 other chimpanzees. But when Goldsborough approached him, he knew something was wrong. Muni was holding a baby in her arms and the baby was not moving.

Goldsborough rushed to the room where the zookeepers were preparing food for the chimpanzees and told them what he had seen. At first, they didn’t believe Goldsboro’s words and said that Mooney was probably playing some tricks. But after the guards saw the baby with their own eyes, they entered the compound and tried to take it from Muni. Mooney wouldn’t let go and the guards decided to wait for a while and then try again.

At this moment, another female chimpanzee named Toshi was roaming around Muni. Toshi was one of Goldsboro’s favorite chimps. A few years ago, he became world-famous for a planned attack on a drone that was filming chimpanzees. Toshi had experienced a miscarriage long before. Maybe for Toshi, seeing Muni and her baby was a reminder of that old memory or similar feelings. Over the next two days, she stayed close to Mooney, while Mooney still held her baby’s body in her arms.

Finally, in a struggle with the guards, the body falls from Mooney’s hands, Toshi takes it and refuses to give it back. Muni was very angry. The guards put Toshi in a separate room and Muni angrily bangs on the door. Goldsborough was not sure about the cause of this behavior. Mooney seemed to be under the influence of intense maternal attachment, and Toshi was perhaps reacting to a repetition of feelings she had experienced in the past.

It is unclear whether any of the chimps actually understood what had happened to the child. Maybe they mistakenly thought the child would come back to life. Even though chimpanzees are our closest relatives in the tree of life and one of the most well-studied animals, we still cannot interpret their behavior with certainty.

An old question

chimpanzee

Last June, more than 20 scientists gathered at Kyoto University in Japan for the largest-ever conference on comparative morphology (the study of animals’ experience of death). Although this scientific field is small, its works date back to the time of Aristotle. In 350 BC, Aristotle wrote about a pair of dolphins he saw coming to the surface of the Aegean Sea supporting a dead baby, “out of compassion trying to prevent it from being eaten.”

Much of the scientific literature on comparative mortology contains similar stories. Some of them are short, like Aristotle’s story, and some, like the story of Muni and her baby, published in 2019 in the journal Primates, contain much more social detail.

Scientists want to find out what emotions animals experience when they lose loved ones. They are trying to understand if animals fear death like we do. However, there are many obstacles in the way of studying this issue. Researchers cannot interview animals. While hormonal changes can be observed (cortisol levels rise in bereaved baboons), these changes may be caused by other stressors.

So far, the best comparative mortality data have come from observing animals in the wild or captive animals in zoos, but even here there are problems.

Species with more interesting responses to death (such as nonhuman primates, whales, and elephants) have long lifespans and low mortality rates in their societies. Obtaining systematic data on their response to death usually requires years or even decades of study.

Alecia Carter, an evolutionary anthropologist at University College London, says she has identified a group of about 1,000 rhesus monkeys on Cayo Santiago Island, off Puerto Rico, that would be ideal for such studies. Rhesus monkeys are very social and usually live 15 to 20 years, which is enough time to establish deep relationships; But it is not so long that deaths among them are very rare.

Understanding of death

the monkey

Humans have spent months in hot, humid forests or zoo enclosures and overcome difficult obstacles to study animals’ reactions to death. Anyway, we humans have been sensitive to death, if not very much, at least since the beginning of written history. The oldest work of epic literature tells the story of King Gilgamesh and his struggle with death. “Death is sitting in my bedroom and everywhere I turn, I feel death,” he says, searching for a plant that promises immortality.

Between the ages of 4 and 7, human children learn that death is an irreversible situation

Human cultures have devised symbol-laden rituals for the pre-death and post-death periods. For more than 10,000 years, we have buried our lost children in the ground and planted flowers around them. We are the species of faithful guardians of tombs, builders of pyramids, and inventors of various funeral ceremonies. We have envisioned the afterlife both in heaven above and here on earth on the wheel of reincarnation. Our philosophers have also dealt with the issue of death in a very subtle way, and their definitions of death currently exceed 10,000 words.

We humans have even extended our finitude to the universe itself. Scientists tell us that trillions of years from now, after the last galaxies have collapsed and the black holes have vaporized bit by bit, the entire universe will be destroyed.

As humans, our complex ideas about death are not passed on to future generations through our genes. They are formed in people’s minds over time and gradually accumulate in our culture. Human children usually learn between the ages of 4 and 7 that death is not temporary or irreversible, and if they lose a family member or pet, they may understand this a little earlier.

In a new book, ” Pretending to Die: How Animals Understand Death, ” Spanish philosopher Susana Monceau argues that many other animals probably understand the same simple concept of death (i.e., loss of agency). Of course, without access to their minds, we cannot be sure about this.

Mammals, fish, birds, reptiles, and insects are all aware of agency in the natural world. They monitor their environments for movement and differentiate between stationary objects and things that move in some way to achieve their goal. Some of them behave in ways that show they understand that other animals may lose this ability forever. But we don’t know whether these behaviors are caused by the understanding of death or simply by instinct.

Pay attention to the termites. At the June meeting in Kyoto, an entomologist from Louisiana State University presented a paper on carcass management methods in eastern groundhogs. More than a million of these insects may congregate in nested subterranean colonies tens of meters wide. When worker ants encounter a dead mate in one of the colony’s tunnels, they react differently depending on the condition of the corpse. When the corpse is fresh, they eat it; But they bury old and rotten bodies. Other social insects that live in similar environments behave in similar ways. Bees remove dead bodies from the hive, but these behaviors do not appear to be caused by an understanding of the concept of death.

Termite corpses produce oleic acid, which apparently stimulates burial behavior. When the American biologist Edward Wilson smeared a live ant with this substance, the members of the colony immediately assumed him dead and took him out of the colony, even as he moved his legs in protest.

Death is a complicated concept for us

giraffe

Chimpanzees are not like termites. Their large and complex brains are better able to understand concepts such as death, and there is evidence that they experience an emotion similar to grief.

Several species of non-human primates will gather around a recently deceased member of the community and in many cases gently touch the lifeless body. The population usually disperses slowly and regularly: those who were closest to the dead animal stay longer. Jane Goodall observed that an eight-year-old chimpanzee stayed with its mother’s corpse so long that it died.

Other mammals also usually gather around their dead. While doing this, the giraffes shake their necks at the scavengers to keep them away. In India, the bodies of five young elephants were found covered in twigs and leaves, leading some scientists to believe they were buried by other members of the group.

Andre Gonsalvez, a comparative morologist at Kyoto University, cautions against paying too much attention to this story. According to him, the elephants were found in the pit; This means that they could have fallen inside them, and leaves and dirt could have accidentally piled up on the bodies as their families tried to pull them out.

Monceau reminds his readers that animals live in a violent and bloody world where predators attack in the dark of night or appear from unseen heights with sharp claws.

The violent environment of animal life provides rich conditions for understanding death. Monceau gives the example of a young stag watching a battle between two older stags for power. After their antlers clash several times and the weaker rival fails to rise, the young deer begins to understand the basics of death. If he does not remember this lesson, he will probably have many opportunities to learn it again.

Even if chimpanzees understand the concept of death, it is not as complicated for them as it is for us

Gonsalves isn’t sure if animals learn the meaning of death in their communities and says many animals eat other animals while they’re still alive. It is not clear if they are trying to cause their death or if they perceive it as a separate state of existence. They might just be trying to get a moving food source into their mouths, like frogs, who stick out their sticky tongues at anything that looks like a moth simply as an instinctive reaction.

Among chimpanzees, acts of brutal violence, including murder, indicate a deeper understanding of death. Chimpanzees, like wolves and lions (and humans), sometimes cooperate to kill rival group members. These attacks may be planned in advance. Two or three males enter an area occupied by another group. They move quickly and cautiously, and even when they pass food sources, they don’t stop to eat. They choose single targets and coordinate their attacks so that they don’t get hurt themselves. In some cases, the attacking chimpanzees will continue their attacks even after the victim has surrendered, only stopping when the victim stops breathing.

Obviously, even if chimpanzees understand the concept of death, it is not as complex for them as it is for us. Humans know what death is and they know that one day it will come to them.

James Anderson, professor emeritus of Kyoto University and known as the father of comparative mortology, says chimpanzees feel about their own death in a different way than we humans do. Despite thousands of hours of observation, he says, no one has ever seen a chimpanzee attempt suicide. According to Anderson, only an animal that knows it can die tries to bring about its own death. He says that the lack of reliable reports of suicidal behavior in chimpanzees or any other animal suggests that the existential burden of death is uniquely ours.

Of course, Anderson, as well as other scientists specializing in the field of comparative mortality, still cannot provide the final answer. They can tell us that chimpanzees understand death better than termites, but the rest is unknown and may never be revealed. We can only hope that as we continue to study chimpanzees, we will see new behaviors from them that will reveal more of their inner world.

The story of Muni and her baby may be one of these cases. After the zookeepers left Toshi alone, they decided to calm things down. They kept him away from others until the next day. Meanwhile, everything had changed for Mooney.

Muni used to have trouble interacting with other chimps and used to pull the hair of other female chimps tightly during grooming. He often sat too close to them and stared at them inappropriately. The day Toshi returned to the group, Mooney was surrounded by other chimpanzees. When he saw Toshi, he quickly got up and slapped him.

Toshi did not react, and over the next 30 days, she and the other chimps interacted more with Moony. No other chimpanzee experienced such an increase in attention, and almost all chimpanzees participated in this display of attention. They hugged Moony and petted her more, but they didn’t share the attention equally. Some took care of Muni more than others and Toshi took care of him most of all. It seemed that an important topic had been exchanged between these two chimpanzees. A few months later, things in the compound were largely back to normal. Muni was no longer being petted and the males started harassing her again. But Toshi and Muni often sat together and this close relationship continues to this day.

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Mammoth and dodo return to nature

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mammothNoun: Any species of the extinct genus , of large, usually hairy, elephant-like mammals with long curved tusks and an inclined back, which became extinct with the last retreat of ice age glaciers during the late Pleistocene period, and are known from fossils, frozen carcasses, and Paleolithic cave paintings found in North America and Eurasia.

Noun: A mastodon.

Noun: Something very large of its kind.

Noun: A kind of large donkey.

Adjective: Comparable to a mammoth in its size; very large, huge, gigantic.

Noun: Any species of the extinct genus , of large, usually hairy, elephant-like mammals with long curved tusks and an inclined back, which became extinct with the last retreat of ice age glaciers during the late Pleistocene period, and are known from fossils, frozen carcasses, and Paleolithic cave paintings found in North America and Eurasia.

Noun: A mastodon.

Noun: Something very large of its kind.

Noun: A kind of large donkey.

Adjective: Comparable to a mammoth in its size; very large, huge, gigantic.

Scientists are now on the verge of restoring several iconic species, such as the woolly mammoth and the dodo, from extinction. But the consequences of de-extinction may not be in our favor.

Mammoth and dodo return to nature: will de-extinction save the environment?

Summary of the article:

  • In 2003, scientists were able to bring an extinct species back to life for the first time. The experiment resulted in the successful cloning of a Pyrenean ibex, but the clone died minutes after birth. The project ultimately failed, but this achievement became the foundation of a new field called “de-extinction”, which has made significant progress in the last two decades.
  • Companies such as Classel Biosciences are advancing projects to recover iconic extinct species such as the woolly mammoth, the dodo, and the Tasmanian wolf. The aim of such projects is to increase biodiversity and restore the vital roles of these species in the environment. However, some experts are skeptical about the possible consequences of species recovery.
  • The most important challenges include genetic limitations, the possibility of disease in restored species, and unforeseen effects on natural ecosystems. Critics say that it is better to invest in the protection of existing and endangered species.
  • In contrast, proponents of de-extinction believe that such new technologies can also lead to the conservation of existing species and scientific innovation. But the question remains, will the de-extinction of extinct species be an effective solution to the environmental crises of today?

In 2003, scientists managed to bring an extinct creature back to this world for about seven minutes. The restored species was the Pyrenean ibex ( Capra pyrenaica pyrenaica ) and the last known member of the subspecies was a female named Celia. Celia had died three years before recovery.

Before Celia’s death, scientists took a DNA sample from her ear and injected her genetic material into an egg with the nucleus removed from a domestic goat. The result of this effort was the birth of a clone. The born clone became the first and only creature to return from extinction but died soon after his birth due to a lung defect.

Although the efforts of scientists to create a healthy animal were not successful in the end, it became the foundation of the science of ” de-extinction “, which has experienced a lot of progress in the last two decades. Technology no longer stands in the way of reviving recently extinct species and, in many cases, provides access to enough DNA to create efficient genomes and clones. The question is not whether we can restore lost species, but whether we need to.

The disastrous results of recovering extinct species should not be ignored

Some companies have not waited to answer such questions. For example, Classel Biosciences, a biotechnology and genetic engineering company based in Texas, plans to revive three iconic extinct species: the dodo ( Raphus cucullatus ), the Tasmanian wolf or Tasmanian tiger ( Thylacinus cynocephalus ), and the woolly mammoth ( Mammuthus primigenius ). According to Classel’s website, the ultimate goal of de-extinction efforts for such species is to “enrich biodiversity, restore vital ecological roles, and strengthen ecosystems’ resilience.”

However, according to some experts, the disastrous results of recovering extinct species cannot be ignored. Oswald Schmitz, a professor of population and community ecology at Yale University, told LiveScience: “Our pride as humans makes us think we have the ability to control our technology. But I’m not so sure.”

Even at best, environmentalists face skepticism; Is reviving organisms that have been extinct for centuries or thousands of years as beneficial as preserving those that are still alive? “What’s gone is gone,” says Schmitz.

Two extinct birds on a white backgroundThe last Dodo died out in the 1600s. But Klaasel is planning to bring the flightless bird back and reintroduce it to the island of Mauritius.
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Recovery of extinct species, is closer than we imagine

Ben Lam, co-founder and CEO of Classel, says recent advances have brought scientists closer to recovering extinct species than people realize. Referring to other de-extinction projects of the Klaasel company, he added: “The company plans to produce the first mammoth-like calves by 2028, and it is very likely that we will see the recovery of another species before then.”

Woolly mammoths lived in the Arctic between 300,000 and 10,000 years ago. To produce mammoth calves, Klassel scientists will first identify the genes encoding the woolly mammoth’s iconic physical characteristics, such as woolly hair, curved tusks, fat deposits and a dome-shaped skull. Then, they will insert these genes into the genome of Asian elephants ( Elephas maximus ), which are genetically more similar to mammoths than other species.

The first mammoth-like calves will be produced by 2028

Love Dalen, a paleontologist and professor of evolutionary genomics at Stockholm University, says that de-extinction can have many different meanings, and our ability to do so depends on how we define it. De-extinction, which means “creating a hybrid species that resembles an extinct species by replacing a limited number of key genes,” is only possible if the DNA of the extinct species is available, adds Dahlen, who is on Klaasel’s advisory board. For example, dinosaur DNA doesn’t exist, so making Jurassic Park is just a dream right now.

Creating an animal that is genetically identical to an extinct species is more complicated and depends on the species. Recovery is likely to be possible for recently extinct species for which higher-quality DNA samples are available, such as Celia, Dahlen says. But this does not apply to mammoths.

Dahlen and his colleagues are close to sequencing the entire woolly mammoth genome, but a few regions of the DNA, such as some strands of the repetitive code, remain challenging.

So far, Klaasel has obtained more than 60 incomplete woolly mammoth genomes, which he will use to edit elephant genomes in the lab. Once the scientists have the final DNA sequence, Lam says, they will place the elephant-mammoth hybrid embryo in the womb of an Asian or African elephant ( Loxodonta ).

Classel also has plans to restore the Tasmanian dodo and wolf. “For Project Dodo, we have a genome that is almost complete,” says Lam. “But for Tasmania, which became extinct in the last century, we had much better genetic data from the beginning.”

Klassel plans to transplant the genetic material to domestic chickens ( Gallus domesticus ) to restore the dodo and to small mouse-like marsupials called Sminthopsis crassicaudata to restore the Tasmanian wolf.

Two woolly mammoths fight in the snowUsing DNA extracted from the tusks and skin of woolly mammoths preserved in the frozen soil of the Arctic, scientists succeeded in reconstructing the genome of the woolly mammoth.
Alamy Stock Photo

Filling the empty space of ecosystems

Ronald Gaudry, an ecologist and director of the Tauros Foundation, an offshoot of the Restoring Europe Wilderness project, which is looking for a replacement for the extinct ago ( Bos primigenius ), says de-extinction aims to fill ecological niches left empty since the original species disappeared. . Niagaos were wild ancestors of domestic cattle ( Bos taurus ) that once lived in North Africa, Asia, and almost all of Europe. They probably played a vital role in maintaining the animal and plant biodiversity of ecosystems by grazing and trampling the soil.

Gaudry and his colleagues are now restoring the Niagaos through a method called reintroduction. This practice does not require genetic engineering. Niagaos were exterminated by humans in 1627, but their DNA is still present in the ancient cattle breeds of southern Europe. By selecting and breeding cows with physical, behavioral, and genetic characteristics similar to Niagaos, ecologists are moving towards the revival of this extinct species. “In every generation, we see rapid and dramatic improvements,” Gaudry says.

The Pleistocene era was the heyday of woolly mammoths. They maintained arctic grasslands by trampling snow, preventing the growth of trees and shrubs, and dispersing nutrients over long distances through feces. Without mammoths and other giant herbivores that are now extinct, such as the Mammoth Steppe, the area has become a waterlogged landscape of tundra, bogs, scrub, and forests. Research shows that the new landscape stores less carbon than grasslands.

Permafrost also melts faster, releasing large amounts of carbon into the atmosphere. Some scientists suggest that reintroducing herbivores to the Arctic will help restore ecosystems, increase carbon storage capacity, and mitigate climate change.

Bringing the giants back to the North helps to reduce climate change

The dodo was one of the largest land animals in the ecosystem of the island of Mauritius. The evidence indicates that beetles spread the seeds of plants and as a result, they have affected the growth of vegetation in the area; However, some experts are skeptical about the role of birds in ecosystem formation. Klaasel’s dodo recovery plans will rid Mauritius of invasive species so the birds can thrive, says Lam. The company argues that dodo recovery will benefit other species as well, as a “halo effect”. The company plans to partner with the Mauritius government in collaboration with the Mauritius Wildlife Foundation.

Also, according to the TIGRR laboratory of the University of Melbourne, which is conducting research in the field of de-extinction, the Tasmanian tiger was the only predator at the top of the marsupial pyramid on the island of Tasmania. Thus, the existence of this species is very important for maintaining predator-prey relationships and, as a result, for stabilizing the ecosystem.

Obsonur Basin, a watershed in Mongolia and the Republic of Tuva (in Russia), also known as Lake YusThe Obsonor Basin is a watershed in Mongolia and the Republic of Tuva (in Russia), also known as Lake Yus. This basin is one of the closest ecosystems today to a suitable habitat for the Steppe Mammoth. Scientists say that the recovery of mammoths will restore this lost ecosystem in the Arctic.
Photographer: Alexander Leshenok / Wikimedia Commons

Increase scalability

However the de-extinct species can fulfill their ecological role properly only if they survive in nature and the population grows sufficiently. Gaudry says that achieving this in the recovery of mammoths is a huge and outstanding task.

Researchers recently estimated that the vast area of ​​Alaska’s North Slope could be a good host for 48,000 woolly mammoths.

Vincent Lynch , an evolutionary biologist and assistant professor at the University of Buffalo, says mammoths’ ecological role may also include increasing the albedo effect (the reflection of light by snow into space and cooling the Earth). But for mammoths to do their job properly, they probably need to be restored across the Arctic.

“You can’t just put mammoths in Alaska and solve the permafrost problem,” Lynch adds. You have to spread them everywhere.”

Lynch believes that there would need to be hundreds of thousands of mammoths on Earth to see a significant impact on climate, and this could threaten living and endangered species.

The Asian and African elephants that Klaasel plans to use as hosts for raising mammoth calves are themselves endangered. An elephant carrying a mammoth fetus cannot give birth to its own children. In this way, this issue will reduce the population of elephants.

Another option is to place embryos in artificial wombs. But the technology is still not fully developed, Lynch says: “Imagine having hundreds or thousands of artificial wombs in warehouses producing genetically engineered mammoths; It’s like a horror and anti-utopian story.”

Unintended consequences

In addition to technical challenges, the restoration of extinct species can have serious consequences. One of the problems is that the regenerated animals may be sick because their genetic diversity is very limited.

To maintain a population, a sufficient number of organisms that are genetically different are needed so that the species is resistant to disease and harmful mutations.

Also, if large-scale mammoth recovery goes awry, who will be responsible? “Biomes have adapted to the absence of mammoths since they went extinct,” Lynch says. What happens if something bad happens?”

Other experts also share such concerns. “To see an impact, there needs to be a large number of animals,” says Sophie Monzara, an ecologist and director of the European Nature Restoration Projects.

Species recovery may lead to conflict between humans and animals

The return of species to nature may also lead to conflicts between humans and wildlife. “In Africa, if you look at elephant conservation and reimportation, you see that there are conflicts,” says Monzara. In Kenya alone, conflicts between humans and elephants killed 200 people between 2010 and 2017. If scientists succeed in producing a viable population of mammoths, they will need to implement nationwide education programs for people to learn how to respond to mammoths.

The composition of regenerated populations is also important. “Brown bears ( Ursus arctos ), which were reintroduced from Slovenia to the Italian Alps in the 2000s, are now thriving, but the original population turned out to be very aggressive,” says Schmitz. “The ecologists did not investigate properly and now these bears are attacking livestock and even humans.”

Schmitz also adds that there is no guarantee that the animals will remain in the same release location. For example, in 1995, gray wolves ( Canis lupus ) were reintroduced to Yellowstone National Park, but they crossed the park boundaries. “If you release the creatures into the wild, they will look for places that are more suitable for them, and those places may not be where you thought they would stay,” he says.

Although herbivores helped store carbon during the last ice age, Love Dallen says, “The recovery of megafauna may have a negative impact on climate change.” For example, mammoths may contribute to global warming by breaking down frozen soil and releasing methane in the warm season. Also, like elephants in the African savannas, by eating plants, they may also reduce the amount of carbon stored in woody plants .”

The last known Tasmanian tiger died in 1936 at Hobart Zoo in TasmaniaThe last known Tasmanian wolf died in 1936 at Hobart Zoo in Tasmania. If this species becomes extinct, it will compete with another animal called the dingo in Australia, which is currently in danger of extinction.
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A pet project for billionaires

While proponents of restoring extinct species cite this as a valuable way to protect the environment, critics argue that investing in conservation programs for existing species is far more effective. Classel has raised at least $225 million so far for its endangered species recovery programs, with a portion of that money going toward conservation and genetics research around the world.

“Instead of using this money to bring back three extinct species with unknown environmental impacts, these funds could be used to save about 100 species that currently face an uncertain future,” says Schmitz.

The best way to support and protect the environment is to invest in proven projects

The goal of species restoration in some cases is organisms that have similar living equivalents that play the same role in ecosystems. For example, one of the reasons for the Tasmanian extinction was that people knew them as livestock hunters. “Right now, we have a similar animal called the dingo or the Australian wild dog ( Canis lupus dingo ) that is facing the same problems as Tasmania,” says Schmitz.

Lynch believes that the best way to support and protect the environment is to invest in existing and proven projects. “Reviving many extinct species with significant environmental impact is likely to be impossible, raising questions about the purpose of de-extinction companies like Klaasel,” he says.

Adam Cyril, a researcher in cultural, historical, and environmental geography at the University of Nottingham, believes that species recovery is unlikely to help solve environmental crises. “The purpose of this project is literally to provide a pet for billionaires,” he says.

In response to Cyril’s criticism, Lam says, “Any species recovery goal requires new technology and techniques that will also benefit closely related species.” He also argues that “technological innovations developed and financed by private companies are very important in this regard.”

Still, aside from Classel’s environmental impact, the return on such a huge investment would be huge, Lynch says. He adds: “I have no doubt that this project will succeed, they will make a lot of money if it succeeds.”

But in the end, says Schmitz, the harms and losses of de-extinction to other people and to nature will far outweigh the benefits.

As a result, the revival of extinct species is technically possible, and with recent advances, it is one step closer to becoming a reality. However, there are serious ethical, environmental, and scientific questions that must be addressed before de-extinction. Critical researchers say that instead of focusing on the recovery of lost species, we should focus on preserving and supporting the species that are still alive and their habitats.

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Environment

If the dinosaurs did not become extinct, what would our world be like today?

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Have you ever wondered what our world would be like if the dinosaurs had not gone extinct? Join us in this article to answer this question.

If the dinosaurs did not become extinct, what would our world be like today?

Sixty-six million years ago, an asteroid with the power of 10 billion atomic bombs hit Earth and changed the course of evolution forever. The sky became dark and the photosynthesis of plants stopped. First, the plants and then the animals that fed on them were destroyed, the food chain collapsed and more than 90% of the species disappeared. As the dust settled in the Earth’s atmosphere, all dinosaurs became extinct except for a group of birds. But this catastrophic event paved the way for human evolution. The surviving mammals, especially the early primates, multiplied, and then humans evolved.

The alien dinosaur Odyssey on the beach
Strangely, Odysseus lived about 66 million years ago and was one of the last dinosaurs on earth.

Now suppose that the said asteroid had not hit the earth and the dinosaurs would have been saved. Imagine evolved raptors flying their flag on the moon. Dinosaur scientists discover relativity or discussing a hypothetical world dominated by mammals.

This hypothesis may seem like a science fiction story, but it contains deep philosophical questions about evolution. Did humans evolve purely by chance, or was the evolution of intelligent tool-using creatures inevitable?

Brains, tools, language, and large social groups have made humans the dominant species on the planet. Eight billion wise humans (homosapiens) live on the seven continents of the earth. According to the same weight, the number of humans is more than all the wild animals in the world. Humans have changed half of the earth’s land to feed themselves. In the 1980s, paleontologist Dale Russell proposed a thought experiment in which a carnivorous dinosaur evolved into an intelligent, tool-using creature. This dinosauroid has a big brain and walks on two legs.

Dinosauroid model
Dinosauroid model

This hypothesis is not impossible but unlikely. The biology of an animal limits its evolutionary path. Your starting point determines your ending point. If you get kicked out of college, you can’t become a brain surgeon, a lawyer, or a NASA rocket scientist; But you may become an artist, actor, or entrepreneur. The paths we take in life open doors and close others. This also applies to evolution.

For example, consider the dimensions of dinosaurs. Sauropod dinosaurs, such as Brontosaurus and its relatives, weighed 30-50 tons and grew up to 30 meters in length during the Jurassic period. Their weight was ten times the weight of current elephants and their length was as long as a blue whale. This evolution has been seen in several groups such as Diplodocidae, Brachiosaurdiea, Turiasaurdiea, Mamenchisaurdiae, and Titanosauria.

Giant dinosaurs
Giant dinosaurs and mammals through time

This evolutionary process was also repeated in different continents at different times and in diverse climates from deserts to rainforests, But the other dinosaurs that lived in these environments did not become gigantic giants. The common point of all the above dinosaurs was that they were all sauropods. Anatomical features of sauropods, such as lungs, hollow bones with a high strength-to-weight ratio, metabolism, or all of these, enhanced their evolutionary potential. In this way, these dinosaurs grew in an unprecedented way.

On the other hand, carnivorous dinosaurs evolved into multi-ton hunters with huge ten-meter bodies. During more than 100 million years, megalosaurids, allosaurids, carcharodontosaurids, neovenatorids, and finally tyrannosaurs evolved into giant apex predators.

Brain size relative to body mass

Brain size relative to body mass in dinosaurs, mammals, and birds

Dinosaurs had huge bodies, But they did not have a big brains. In fact, dinosaur brains rarely grew over time. Jurassic dinosaurs such as Allosaurus, Stegosaurus, and Brachiosaurus had small brains. 80 million years later, in the late Cretaceous period, tyrannosaurus and duck-billed dinosaurs evolved with larger brains; But the weight of the T-Rex brain, despite its gigantic body, was only 400 grams. The brain of Volareceptor was only 15 grams. Meanwhile, the average weight of the human brain reaches 1.3 kg.

Dinosaurs entered a new era over time. Small herbivores became more common and bird biodiversity increased. Later long-legged species evolved. It also seems that dinosaurs had a complex social life. They began a herd life and evolved with heavy horns for fighting. However, dinosaurs seem to have replicated themselves, usually evolving into giant herbivores and small-brained carnivores.

In the span of 100 million years of the history of dinosaurs, no trace of progress can be seen in them. Giant long-necked herbivores and massive tyrannosaur-like predators recurred during this interval. Maybe dinosaurs’ brains got a little bigger over time, but there is little evidence for their evolution into geniuses. It is even unlikely that mammals would have banished them. Dinosaurs were one of the dominant species in their environment until the asteroid hit.

However, mammals had different limitations. They never evolved into giant herbivores and carnivores. Rather, they repeatedly evolved with larger brains. Examples of large brains (human brain size or larger) are seen in orcas, sperm whales, baleen whales, elephants, leopards, and monkeys.

Tamarin, South American monkey
Golden lion tamarin, South American monkey

Today, few descendants of dinosaurs (birds such as crows and parrots) have complex brains. They can use tools, talk, and count; But mammals such as monkeys, elephants, and dolphins evolved with larger brains and more complex behaviors; So can we say that the elimination of dinosaurs ensured the evolution of mammalian intelligence? maybe not

The starting point can determine the ending point, but it cannot guarantee it. Steve Jobs, Bill Gates, and Mark Zuckerberg were all expelled from the university; But not every expulsion from the university leads to this fate. Even if you start at the right point, you need opportunity and luck to continue. The evolutionary history of primates shows that our evolution was not inevitable. African primates evolved in the form of monkeys with big brains in a span of seven million years and ended up with modern humans, But the evolution of primates took a different path in other places.

When monkeys arrived in the Americas about 35 million years ago, they evolved into other monkey species, and primates arrived in North America at least three separate times, 55 million, 50 million, and 20 million years ago. However, they did not become the species that made weapons and smartphones. Rather, they became extinct for reasons we do not know.

Only in Africa did evolution take a unique path. Perhaps something special about the fauna and flora or the geography of Africa caused apes to take a different evolutionary path and become tool-using primates with large bodies and brains. Even with the extinction of the dinosaurs, human evolution required the right combination of opportunity and luck.

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