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Warming Trends: Katharine Hayhoe Talks About Hope, Potty Training Cows, and Can Woolly Mammoths Really Fight Climate Change?

2024-11-23 12:34:18 My

SCIENCE

A Mammoth Furor

Critics are questioning claims by a start-up biotechnology company that a genetically engineered version of the woolly mammoth could help alleviate climate change and restore Siberia’s grassland ecosystem to its Pleistocene heyday.

Colossal, a company founded by technology entrepreneur Ben Lamm and Harvard geneticist George Church, announced Sept. 13 that it had received $15 million in funding to develop a hybrid mammoth-elephant, using CRISPR technology to introduce mammoth genes into an Asian elephant genome. The first calf, Lamm said, could be born within four to six years. The hybrid creature would have notable features of the extinct proboscidean, like small ears, a domed head, long fur, cold-tolerant blood and optimal fat distribution.

Some scientists have been highly skeptical about the project’s chances of success. But critics are especially dubious about Colossal’s claim that a herd of woolly mammoth-elephants could help save the planet from the climate crisis. And it has not escaped attention that, at a time when global warming is receiving unprecedented attention, many companies are suddenly discovering a climate link for their products. 

The company’s head of biological sciences, Eriona Hysolli, said that a population of giant hybrids could knock down slow-growing, heat-absorbing trees and stomp out shrubs and mosses that have taken over the landscape in the millennia since mammoths went extinct. That would make way for fast-growing grasses that keep the soil cool and store carbon in their deep roots. 

Hysolli points to Pleistocene Park as an example of the role large herbivores can play in ecosystem restoration. The 40,000-acre park in Siberia has used horses, bison, yaks and reindeer to bring back the grassland ecosystem.

Yet Vladimir Romanovsky, head of the Geophysical Institute Permafrost Laboratory at the University of Alaska Fairbanks, said he doubts that the hybrid mammoth-elephants, even if they could be created, would knock down trees in Siberia to save permafrost: The animals, he said, were more likely to stick to grassland and they would be hard-pressed to survive in forested areas. 

“There is no other solution than to stop the warming of the climate,” Romanovsky said of  permafrost melting as a result of climate change. “Because on this scale, you can not do anything artificially to preserve permafrost.”

The reason the grassland ecosystem disappeared, Romanovsky said, wasn’t because the mammoth went extinct. It was because the climate changed. Grasslands dominated Siberia in the late Pleistocene, when temperatures were several degrees cooler and conditions were very dry, he said. But as the Holocene led Siberia into a warmer and wetter era, the landscape shifted to a less productive, mossy and forested ecosystem that couldn’t support large mammals like the mammoth. Romanovsky said the grassland cannot be returned simply by reintroducing large mammals, especially since Siberia is warming at a rate faster than the global average temperature, according to the Intergovernmental Panel on Climate Change.

Romanovsky compared Colossal’s solution to putting fish where there used to be a lake. “What they’re suggesting is bring the fish back, put them in this dry lake and water will come.”

Tori Herridge, an evolutionary biologist at the Natural History Museum in London, also did not find the company’s plan for addressing climate change to be convincing. In a Twitter thread last week, she detailed the many unknowns, including how many animals would be needed to have an impact on the climate and how long it would take to get to this point of impact.

“How long would it take to make several 100,000 mammoths, or even 20?” Herridge said in an interview with Inside Climate News. “That’s a lot of time, and so it just feels implausible. You’ve got to admire the ambition, right, but of all the solutions you could come up with, it seems like the slowest way in.”

CULTURE

A Conversation about Hope and Healing with Katharine Hayhoe

A new book by climate scientist and communicator Katharine Hayhoe argues that there is still hope for our planet amid the climate crisis.

The book, called “Saving Us: A Climate Scientist’s Case for Hope and Healing in a Divided World,” lays out a blueprint for how to talk to others about the daunting challenges posed by global warming, centered around finding out what each person values the most and then connecting it to climate change. Inside Climate News recently talked to Hayhoe about her new book. This conversation has been lightly edited for length and clarity.

Why did you decide to write this book?

I’ve heard so many stories of people and I’ve had so many conversations with people about, ‘How do you talk about [climate change]? How do you not talk about [climate change]? What doesn’t work, what does work?’ And most of all, ‘Where do we find hope?’

And what I found is that when we lack a sense of efficacy, which is just a simple idea like, if I do something, can I make a difference? If we lack efficacy, we don’t act. And even among people who are alarmed about climate change, a lot of people aren’t acting. So why aren’t we acting? 

What’s holding us back often is, we’re sort of waiting for hope. We’re waiting for hope to knock at the door of our minds, but the way the world works today, hope does not knock at the door of our minds. To find hope we have to go look for it. We have to take action, we have to use our voice to connect with other people. We have to band together with others and act together, and that is where we find that hope.

You often draw on your experiences as a scientist and a Christian. How has your faith informed your perspective on climate change?

Climate change is not only an environmental issue. It’s also a health issue, and who doesn’t care about their health? It’s an economic issue. A lot of people care about the economy. It’s a resource scarcity issue, and most of all it’s a poverty issue, it’s a hunger issue and it’s a humanitarian issue. Climate change is a human issue. 

It says in the beginning of the Bible that God gave humans responsibility over every living thing. And then all through the Bible it talks about how important the most seemingly insignificant aspects of nature are, and then all through the New Testament, it talks about how, as Christians, we’re supposed to be recognized by our love for others. 

You have this entire arc that I think can be characterized by one word, which is love. Loving others, loving every living thing, caring for others. And so that’s what made me decide to become a climate scientist, and that’s what motivates me. 

The title of the book makes a big promise: a case for hope. How do you maintain hope knowing what you know and doing the work that you do?

Hope often starts in a very dark place. Hope starts from recognizing it’s bad. And it’s going to get worse. And it’s going to take a lot of work to end up in a better place, and it’s not guaranteed that we’re going to get there. But hope follows from action. 

So what the book tries to do is to share so many stories of individual people—not important people, not big people, not CEOs or celebrities or presidents or politicians—but just really ordinary people, like every single one of us reading the book, who use their voices to advocate for change. Because the only way the world has ever changed before is when ordinary, average people decide, you know what, the world can and must be different. 

SCIENCE

A ‘Grim Outlook’ for Norwegian Polar Bears 

As melting sea ice fragments polar bear habitats, the Svalbard population of the species is rapidly losing its genetic diversity, a new study has found, making the bears susceptible to disease, genetic disorders and environmental changes.

Researchers in Norway examined genetic data from polar bears in the Svalbard Archipelago in the Arctic Ocean from 1995 to 2016. They found that the Svalbard population lost 3 to 10 percent of its genetic diversity over the study period, almost certainly because of the loss of sea ice in the archipelago.

“It was quite shocking over such a relatively short time span of 20 years,” said study co-author Simo Maduna, a postdoctoral researcher at the Norwegian Institute of Bioeconomy Research.

Sea ice loss has gradually isolated the Svalbard bears from the larger polar bear population, Maduna said. Without outside bears coming into the area to mate, the polar bears breed within their own population, leading to more matings between closely related animals. 

Genetic diversity is not only important for protecting against disease and avoiding unhealthy genetic traits, Maduna said, but also for resilience and readiness to evolve in the face of a changing climate. 

“If there is no genetic variation or there is limited genetic variation, then of course, how would the population evolve?” he said. 

There is not much that conservation scientists can do to improve the genetic diversity of the Svalbard polar bears, Maduna said. They cannot simply build ice bridges to connect isolated populations. And although the population could recover in ways that scientists can’t see right now, Maduna said, future projections of genetic diversity show substantial losses in the generations to come. 

“The outlook is very grim, to be honest,” he said.

SCIENCE

Potty Training for Cows

Can cows be potty trained? About as easily as children can, a new study suggests. Researchers in Germany showed that calves can be trained to urinate in a designated area. In their experiment, 11 of 16 calves successfully entered a fenced-in “latrine” area to urinate about 75 percent of the time. The calves learned through a reward and punishment method: when a calf urinated in the latrine, it received molasses or barley. When a calf urinated in the alleyway leading into the latrine, it was sprayed with an unpleasant blast of water.

The finding is important because waste from cattle operations emits greenhouse gases that contribute to climate change. And when urine and feces combine in a space such as a barn, they form ammonia, a compound that can pollute nearby soils and waterways. But if cows can be trained to urinate and defecate in a single place, where the waste could be collected and treated, the environmental consequences could be reduced without confining the cows to a single small space. 

Neele Dirksen, a Ph.D. student at the University of Rostock in Germany and a co-author on the study, said, “We have shown that the calves are able to receive internal signals. So they think, ‘Well, I have to urinate in a few minutes, seconds, whatever,’ and they enter the latrine.”

The next step in this research is to figure out the optimal age to train the calves, and potentially to automate the training process, Dirksen said. 

“With our procedure, it’s not practical for the farmers because it takes a lot of labor and time,” she said. “But if we can automate the training procedure, then it could be possible.”

SOLUTIONS

The Power of a Foot on the Floor

Could the lamps in your home one day be powered by pacing around on the wood floor in your kitchen? Possibly, say researchers in Switzerland, who have found a way to harness the energy from stepping on a wood floor to create sustainable power. 

The process is detailed in a new study in the journal Matter, published earlier this month. It relies on the triboelectric effect, in which two different materials exchange electrons when rubbed together, the same effect that makes your hair stand up after brushing it. 

Wood is a common material used in buildings but it is triboneutral, meaning it does not easily accept or give up electrons. But the researchers wanted to find a way to modify the wood to increase its triboelectric effect. 

Co-author Guido Panzarasa, a group leader in wood materials science at the Institute for Building Materials at the public university ETH Zürich, noted that wood is a sustainable, renewable building material that sequesters carbon, and technology that allows wood to harvest energy could become a clean and efficient power source in future sustainable buildings. 

“These kinds of devices could improve the energy efficiency of buildings in many ways,” Panzarasa said. “They are able to extract the energy from sources which otherwise would just get wasted.” 

Panzarasa and his team constructed a floor with two layers of wood. On one layer, the researchers grew a nanocrystalline layer of metal ions that attached to the organic molecules on the wood, which created a tribo-positive surface that would give away electrons. On the other wood floor layer, they applied a silicone coating that formed a tribo-negative surface that would accept electrons. The two modified surfaces made contact with each other when the floor was stepped on, allowing the electron exchange to occur and electricity to be generated. 

In their experiment, the researchers were able to power a lamp and a calculator with footsteps on a wooden floor. Panzarasa said he imagines that this technology could generate much more power in a place like a ballroom or a hotel hallway, where many people are walking around. But much more research is needed to get the technology to the point where it could go on the market, he said.

“Wood is a really amazing material,” Panzarasa said. “It is possible to modify it in a variety of ways, enabling it with completely unexpected properties. And so it is, at the same time, challenging, and extremely rewarding, because it’s a kind of approach that really could result in huge benefits for the environment.”

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