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The Secret of the Hummingbird’s Amazing Adaptation

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Hummingbird
With its ability to fly upside down, consume a lot of sugar, and migrate for a long time, the hummingbird has biological wonders and high adaptability that surprises researchers.

The Secret of the Hummingbird’s Amazing Adaptation: From Digestive System to High-Altitude Flight

Summary of the article:

  • The hummingbird is a small bird with amazing abilities. This bird can fly forward, backward, and even upside down. They feed on nectar and enter a state similar to a human coma at night to save energy.
  • Hummingbirds have a special digestive system that quickly absorbs sugar without causing complications such as diabetes. These birds are also adapted to life at high altitudes and cope with thin air and lack of oxygen with their own adaptations.
  • Some species of hummingbirds migrate a long distance of up to 8 thousand kilometers. In these paths, they not only face environmental challenges but also adapt their bodies to harsh conditions.
  • Researchers are now studying the specific characteristics of hummingbirds. Using new technologies, they plan to gain a greater understanding of the specific adaptations of these birds and their applications in the treatment of diabetes and energy optimization in humans.

The hummingbird is one of the most amazing birds known for its fast flight and ability to hover in the air. With their special diet consisting mainly of nectar, in addition to non-stop flight, these small birds also have other unique abilities such as upside-down flight and backward flight. These birds with a very high metabolism consume nectar as much as 80% of their body weight daily and have a special digestive system to prevent problems such as diabetes.

The hummingbird’s digestive system absorbs sugar quickly. To conserve energy during cold nights or when there is a lack of food, they fall into a state similar to a human coma and reduce their body temperature to near the ambient temperature. Despite many biological challenges, such as tolerating high blood sugar levels and long migrations, hummingbirds continue to live in harsh conditions with their critical and exceptional adaptations.

Most people enjoy watching the beautiful little hummingbirds. Native to the Americas, these colorful creatures fly fast, hover among flowers, and tenaciously defend their territory and food sources.

But to the scientists who study these birds, hummingbirds are much more than an entertaining show. Their small size and high metabolism mean that these birds live on the edge. Sometimes they have to completely shut down their bodies or even migrate thousands of kilometers to save the energy needed to survive during the night. The migration route also sometimes passes through the oceans.

A diet rich in hummingbird nectar leads to blood sugar levels that can cause a person to fall into a coma. A hummingbird’s high-speed flight produces such intense G-forces that it can even knock a fighter pilot unconscious. Researchers say that the more they study these birds, the more hidden surprises they find in their small bodies; The body is one of the smallest in the world of birds.

“They are the only birds in the world that can fly upside down and backward,” says Holly Ernst, a conservation ecologist at the University of Wyoming. “They drink pure sugar and they don’t get diabetes.”

Ernst is one of the few researchers who researches how hummingbirds adapt to the extreme pressures of their lifestyle. In the following, we will review some things that scientists have discovered about the unique adaptation of hummingbirds.

Continuous effort

For years, most researchers believed that hummingbirds spent only about 30 percent of their day engaged in energetic activities such as flying from flower to flower and drinking nectar, and spent most of their time resting. But physiological ecologist Anusha Shankar observed these birds closely and found that they often work much harder than previously thought.

The life conditions of hummingbirds are much more difficult than our imaginations

Shankar, who now works at the Tata Institute of Fundamental Research in Hyderabad, India, tried to understand how the broad-billed hummingbird, native to southern Arizona, lived its life. Using different experimental methods, he measured the metabolic rate of these birds in different activities and estimated their total daily energy consumption. By adding previously published data, Shankar was able to calculate the amount of energy consumed by these birds for each minute of sitting, flying, and hovering, i.e. the three main ways a bird spends time.

Shankar then deduced how much time the hummingbirds spent feeding and sitting during the day. Hummingbirds spend most of their time feeding on nectar but hardly feed when flowers are scarce.

“We found it to be very variable,” says Shankar. In early summer, when flowers were plentiful, birds could meet their daily energy needs with just a few hours of feeding and spend up to 70 percent of the day resting. But with the onset of summer monsoons, flowers became scarcer. In one of the areas, the birds spent only 20% of their waking hours sitting and spent the rest of the day feeding.

Shankar says: “That means 13 hours a day! I can never spend 13 hours a day running. “I don’t know how they do it.”

Ruby hummingbird sitting on green plantsRuby hummingbird.
Photographer: Juan Jose Arango / Universal Images Group

Cool birds

Hummingbirds use a special trick to make the most of their energy reserves: when the bird is in danger of running out of energy, it goes into hibernation or false death at night. In this dormant state, the bird’s body temperature drops to about the same temperature as the surrounding air, sometimes only a few degrees above freezing. When the bird is asleep, it is almost comatose, unable to react quickly to stimuli around it, and breathing only intermittently.

According to Shankar’s calculations, the hibernation strategy can reduce up to 95% of the energy required for hourly metabolism on cold nights. Positioning in this position is critical after days when the bird has fed less than usual, such as days after a storm. Also, it helps the birds to store energy and increase their body fat before migration.

The hummingbird goes into a state of false death at night to save energy

Shankar is now investigating the hibernation strategy further, to find out which body parts the hummingbirds prioritize during this state and which gene products are essential for them to be present. “If you’re a hummingbird running on 10 percent of your natural metabolism, what’s that 10 percent that keeps you alive?” he asks.

One class of genes that seem to remain intact during hibernation are those responsible for the bird’s internal clock. “It’s important for them to do things at the right time, even when they’re asleep,” says Shankar. For example, in order for a bird to start the day well, it starts to wake up about an hour before sunrise, much earlier than receiving visible light cues.

Dealing with sugar

Hummingbirds consume about 80% of their body weight in nectar every day in order to provide the energy needed for their very high metabolism. This amount of nectar is equivalent to a person weighing about 70 kg drinking approximately 100 half-liter cans of soda daily. Of course, nectar is often much sweeter than soda.

The human intestine cannot absorb sugar at such a speed. According to Ken Welch, a comparative physiologist at the University of Toronto Scarborough, one of the causes of stomach disease in humans comes from overconsumption of soda or candy. Hummingbirds have leaky guts to deal with the onslaught of sugar. That is, the sugar in such an intestine enters the bloodstream not only through the intestinal cells but also through them. In this way, sugar is quickly removed from the intestine before it causes discomfort. Fast sugar transport, and possibly other adaptations, allow hummingbirds to reach blood sugar levels up to six times higher than those found in humans.

Hummingbird gut is leaky

A very high amount of sugar in the blood can lead to serious physical problems in humans. High blood sugar leads to more binding of sugar to proteins in the body; This process is known as glycation. During the glycation process, blood sugar combines with body proteins and changes their structure. In the long term, excessive glycation can cause several complications such as diabetes and nerve damage.

Welch says it’s not yet clear how hummingbirds avoid problems like glycation, but researchers are getting clues. For example, a study shows that avian proteins have fewer glycation-prone amino acids than mammalian proteins, and other amino acids are usually deep in the protein, meaning they are less exposed to circulating sugars.

Other unknown strategies for dealing with hyperglycemia may have practical benefits for the management of diabetes in humans in the future. “There may be a gold mine in the hummingbird genome,” Welch says.

Metabolic change

One of the challenges that hummingbirds face is the change in metabolism at the end of the day. In addition to this challenge, the nectar diet also involves issues such as high water consumption. Now, let’s take a look at the adaptations of these birds in the face of both challenges.

By the end of the overnight fast, hummingbirds almost completely deplete their body’s sugar reserves. This creates the challenge of reverse metabolism. “How does this bird wake up and fly?” asks Welch. There is nothing left but fat to burn.”

Welch found that hummingbirds are remarkably capable of switching their metabolism from burning sugar to burning fat. “This action requires a huge change in the biochemical pathways involved in the process,” he says, and the change occurs within minutes, much faster than in other organisms. He adds: “If we could also have such control over our fuel consumption, we would be very happy.”

Saving water

Sugar isn’t the only challenge of a nectar-rich diet. After all, nectar is mostly water, and birds that drink such large amounts of fluid must excrete a lot of it without losing electrolytes. For this reason, the kidneys of hummingbirds are specially adapted to absorb electrolytes before re-excreting them. “These birds excrete distilled water,” says Carlos Martínez del Río, a retired physiological ecologist from the University of Wyoming.

Hummingbirds also turn off their kidneys at night

But there is another problem: if the hummingbird produced dilute urine at night, it would die of dehydration before morning. To prevent this, hummingbirds turn off their kidneys every night. “They go into a state that, in humans, is similar to acute kidney failure,” says Martínez del Río. “The hummingbirds have to do this, or they will die out.”

High altitude flight

The metabolic needs of hummingbirds at sea level also become tough enough. But many species live at high altitudes. The thin air at high altitudes has less oxygen and provides less resistance to the air when suspended. For example, the giant hummingbird, the world’s largest hummingbird, lives in the Andes mountains at an altitude of more than four kilometers, higher than many helicopters. According to Jesse Williamson, an ornithologist from Cornell University, to cope with such conditions, the hemoglobin in the blood of these birds is richer.

But some hummingbirds face bigger challenges. The giant hummingbirds are so large that researchers can attach satellite tracking tags to them, as well as smaller locators. So Williamson and his colleagues decided to equip these birds with trackers. After thousands of hours of trying to capture the birds using nets, the researchers were able to attach the trackers to 57 birds using custom-made straps made from jewelry-making straps.

Plot of tracker data attached to the giant hummingbird in the AndesTracking data of giant hummingbirds during migration from Chile to the Andes.
Photographer: JL Williamson/PNAS

Although tracking data was recovered from only eight birds, even this small sample yielded a big surprise: some birds live year-round in the Andes, while others, a separate, previously undetected species, migrate from the breeding grounds every year. They migrate to the Andes mountains on the coast of Chile. This means that birds not only face the obvious challenges of a long migration (a round trip of almost eight thousand kilometers) but also have to adapt to thinner air.

The secret of hummingbirds is gradual adaptation to the conditions

But what is the secret of hummingbirds? They gradually adapt to the conditions. “Their work is similar to the way human climbers climb peaks like Everest, climbing and taking breaks to get used to the conditions,” Williamson says. “The journey takes months.”

As access to lighter and cheaper tracking technology improves, researchers like Williamson hope to be able to track even smaller species of hummingbirds. Tracking, along with other advances in research technology, may hold many surprises about the biology of these amazing little birds.

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Why does Everest get higher every year?

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Everest, the tallest mountain on earth, is getting taller. A nearby river carries the rock and sediments away from the area that made Mount Everest reach its highest height.

Why does Everest get higher every year?

How did Everest become the highest mountain in the world with a difference of more than 200 meters from the next two highest peaks? Geologists say the mountain owes part of its extra height to two ancient rivers that flowed through the Himalayas and merged years ago. The erosion from the new river washed away so much rock and soil that Everest moved up to 50 meters more.

Matt Fox, a geologist at University College London and one of the authors of a new paper that examines the mystery of Everest’s height, says that the outer crust of the Earth responds to the removal of mass by gradually rising, and this is what caused the height of Everest to rise.

Rivers cause erosion, but the effects they have on the land can be unexpected. About 89,000 years ago, a powerful river combined with another river became more erosive. This merging washed away more of the Himalayan land, and the enormous weight of the crust separated the layer of earth we live on.

Mountains may seem static, but they are always moving

At over eight kilometers or 8,848 meters high, Mount Everest is the tallest mountain on Earth and still growing. At almost 250 meters higher than the second-highest peak in the Himalayas, it is unusually tall even for this mountain range. The next three highest peaks differ by only about 120 meters in height.

The large height difference between Everest and other mountains can be partly explained by the uplift force caused by the pressure under the Earth’s crust. The underground pressure started after the erosion of a large amount of rock and river soil, which is a geological phenomenon called isostatic reaction. Revival occurs when a part of the Earth’s crust that loses mass bends and floats upward due to the intense pressure of the liquid mantle beneath it. The upward pressure is greater than the downward gravitational force after the shell loses mass.

Isostatic rebound is a gradual process, moving only a few millimeters per year, but it can significantly affect the Earth’s surface over time.

The isostatic reaction has contributed to the growth of Mount Everest

The lightweight crust was able to float more easily above the lower layer, the mantle, adding 15 to 50 meters of height to Everest, the study says.

“Although mountains may seem static in terms of human life, they are actually constantly moving,” said Jinzhen Dai, a geologist at the China University of Geosciences in Beijing and the author of the paper. Although the paper can only explain part of Everest’s extra height, scientists see it as a step toward calculating how the mountain grew to its current height.

The formation of Mount Everest began about 45 million years ago when the Indian tectonic plate collided with the Eurasian plate. This collision caused a part of the earth’s crust to bend and fold on a huge scale, creating the Himalayas.

Aron River and a bridge over itAron River.
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Although the Earth’s crust appears solid, it is not. When something massive, like an ice sheet or mountain range, weighs down the crust, it bends downward; But the lower mantle is buoyant and pushes the overhanging crust upward.

When the crust neither rises nor sinks, it is in isostatic equilibrium, and Everest must be in that state. As the Indian tectonic plate moves down, it adds new material to the Himalayas, causing the mountains to grow. At the same time, rain, snow, and glaciers wash the surface of the mountain and remove rocks and materials.

The forces of material addition from below and erosion from above must cancel each other out, meaning that Everest does not grow or shrink; But the fact that Everest keeps getting taller suggests that something is upsetting this balance. One possible reason is the erosive river, which strips the surrounding land of material that weighed down the mountain, allowing Everest to rise higher.

In the shadow of Everest is the Aron River, which, like this peak, is more distinct from the surrounding rivers. The Arun takes an unusual course, first flowing along the northern Himalayas and then twisting and turning over the ridge near Everest. This shows that the upper and lower parts of the river were not always connected and that some important event caused the connection.

By simulating the rivers of the region in computer simulations, the researchers found that about 89,000 years ago, another river network gradually eroded and made its way toward the Himalayas until it finally connected to the Arun River. When these two rivers joined together, the first river took the flow of water from Arun and made it part of its network.

The Himalayas could not cope with the erosion power of the river and the crust on top of it was pushed towards the sky by the floating mantle sea, various peaks rose and Everest gained up to 50 meters of additional height.

The tallest mountain on Earth is still growing, growing by the width of a spaghetti strand every year. A combination of factors, including crustal rebound, explains Everest’s height. But Everest’s growth spurt probably won’t last forever. The balance may tip the other way and reduce the height of Everest. Like all mountain ranges, the Himalayas will go up and down.

The findings of the study have been published in the journal Nature Geoscience.

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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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mammoth
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.
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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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