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Life on Earth May Have Been Made Possible by an Ancient, Violent Collision





An artist’s rendering shows a planetary collision near the star Vega. The Moon may have formed from the debris of such an impact between Earth and a Mars-sized body. Credit: NASA

This artistic visualization shows a planetary collision near the star Vega. One new study suggests that the Earth obtained the elements that sparked life from a collision between the proto-Earth and a Mars-sized body that also created the moon. (Credit: NASA)

Life on Earth

Did the violent, cosmic collision that created the moon make life on Earth possible? One new study suggests so.

There are a number of theories for how life originated on Earth, many of which try to explain how our planet got the ingredients for life: elements like carbon and nitrogen.

Previously, scientists have suggested that meteorites delivered life-giving elements to Earth. While the isotopic signatures of these elements on Earth match up with these objects, the ratio of carbon to nitrogen isn’t quite right. While the meteorites thought to have delivered elements crucial to life to Earth (known as carbonaceous chondrites) have 20 parts carbon for each part nitrogen, that ratio is about 40-1 on Earth.

Instead, these crucial elements may have been delivered in a staggering collision, says a group of petrologists at Rice University. Scientists know that a long-ago collision between the proto-Earth and a Mars-sized object created the moon — that same impactor may have also given us the elements for sparking life, they say.

To come to this conclusion, the research team created a simulation of the event based on a series of experiments that tested the behavior of carbon, nitrogen, and sulfur during the process of core formation on a rocky planet. The team then simulated the high pressures and temperatures during core formation and estimated how much carbon or nitrogen might be in a Mars-sized planet with a sulfur-rich core. They ended up with a geochemical simulation that accurately modeled observations of carbon, nitrogen and sulfur on Earth.

A Probable Scenario

With their simulation, along with the known ratios and concentrations of elements on Earth, the team found that instead of a rain of meteorites delivering crucial elements, a more likely explanation is that they came all at once.

“Our simulation results suggested that the most probable scenario of the origin of carbon, nitrogen, and sulfur on the silicate portion of Earth is where these elements are brought by a Mars-sized (8-10 percent by mass of the present-day Earth) planet merging with the proto-Earth,” says Rajdeep Dasgupta, co-author of the paper in an email. Additionally, such a planet would probably have had a core rich in sulfur.

The work doesn’t solve the question of how life originated on Earth, but it does begin to answer the question of how the ingredients for life might have gotten here. “There are many unanswered questions about how life truly originated. Our study, however, provides a mechanism to bring the raw materials needed for life’s recipe,” Dasgupta said.

This work is published in the journal Science Advances. 


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Globe Climate: Canada’s resource reckoning is coming





Good afternoon, and welcome to Globe Climate, a newsletter about climate change, environment and resources in Canada.

This afternoon, the Alberta government announced that it is restoring a coal mining policy it revoked last spring. At the time, the move provoked a widespread public backlash detailed by The Globe. The original decision, which opened up more than 1.4 million hectares to exploration, was made without public consultation. Premier Jason Kenney previously defended the changes.

Lots more on coal and Canada’s resources industry in this week’s newsletter edition.

Now, let’s catch you up on other news.

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‘Incredibly destructive’: Canada’s Prairies to see devastating impact of climate change





As the climate continues to warm at an alarming rate, experts warn if dramatic steps to mitigate global warming are not taken, the effects in Canada’s Prairie region will be devastating to the country’s agriculture sector.

According to Environment and Climate Change Canada, the country is warming, on average, about double the global rate.

Scientists with the National Oceanic and Atmospheric Administration in the U.S. recently found 2020 was earth’s second-hottest year on record, with the average land and ocean surface temperature across the globe at 0.98 of a degree C above the 20th-century average.

However, the agency found the northern hemisphere saw its hottest year on record, at 1.28 degrees C above the average.

“(In Canada) we are looking at about 6.4C degrees of warming this century, which isn’t much less than one degree per decade, which is just a terrifying rate of warming,” Darrin Qualman, the director of climate crisis policy and action at the National Farmer’s Union said.

Qualman said there is “massive change coming” to Canada’s Prairies, which will be “incredibly destructive.”

“It’s not going too far to say that if we made that happen, parts of the Prairies wouldn’t be farmable anymore,” he said.

According to the federal government, in 2018 Canada’s agriculture and agri-food system generated $143 billion, accounting for 7.4 per cent of the country’s GDP.

The sector employed 2.3 million people in 2018. The majority of the 64.2 million hectares of farmland in Canada is concentrated in the Prairies and in southern Ontario.

The effects of climate change are already being felt on the ground in the Prairies, Qualman said, adding that the NFU has already heard from farmers complaining of “challenging weather.”

“People are sharing pictures of flattened crops and buildings, et cetera, that have been damaged,” he said. “And we’re still at the beginning of this.”

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Insect-based dog food aims to cut your pet’s carbon pawprint





Meat has an enormous carbon footprint, with livestock liable for about 15 per cent of worldwide emissions, as we have beforehand mentioned on this e-newsletter. That is prompted specialists to suggest consuming much less meat for sustainability (and well being) causes.

However what about your pet? One research discovered that the methane and nitrous oxide emissions generated by canine and cat meals within the U.S. alone had been equal to about 64 million tonnes of CO2, or roughly the quantity produced by 13.6 million automobiles. And it might be getting worse, with a development towards feeding pets “human-grade” meat.

That is prompted some pet meals makers to look to lower-carbon protein sources — together with bugs.

Research present that producing insect-based meals requires far much less feed, land and water and generates far fewer greenhouse fuel emissions per kilogram than meats comparable to beef, pork or rooster.

That is one of many causes increasingly more pet meals containing insect protein are hitting the market. Purina, a model owned by multinational Nestlé, launched a line of canine and cat meals containing black soldier fly larvae in Switzerland in November.

In Canada, Montreal-based Wilder Harrier began promoting canine treats made with cricket protein in 2015 and pet food made with black soldier fly larvae in 2019. It plans to broaden to launch a line of insect-based cat treats later this yr and cat meals in 2022 due to “a ton of demand,” mentioned firm co-founder Philippe Poirier.

Wilder Harrier initially labored with animal nutritionists on insect-based merchandise to unravel a unique downside — specifically, the founders’ canines had allergy symptoms to frequent meats utilized in canine meals. Poirier mentioned now about half its prospects hunt down the product due to their pets’ allergy symptoms and about half for environmental causes.

Dr. Cailin Heinze, a U.S.-based veterinary nutritionist licensed by the American School of Veterinary Vitamin, has written concerning the environmental influence of pet meals. She mentioned we’re typically “not as involved as we probably ought to [be]” concerning the environmental footprint of pets.

Alternatively, she famous that the longer-term influence of newer diets, comparable to vegan meals and people containing bugs, hasn’t been nicely examined in comparison with conventional pet meals.

Maria Cattai de Godoy, an assistant professor of animal sciences on the College of Illinois who research novel proteins for pet meals (together with bugs, yeast and plant-based substances), mentioned such substances are rigorously examined to find out their security and diet earlier than being added to pet meals. 

“This can be a very extremely regulated trade,” she mentioned, however admitted it is also evolving.

Relating to bugs, she mentioned constructive information “reveals promise in direction of utilizing them increasingly more in pet meals.” Insect-based proteins have additionally earned the endorsement of the British Veterinary Affiliation, which says some insect-based meals could also be higher for pets than prime steak.

However Godoy famous that there isn’t any one-size-fits-all resolution, and pet homeowners ought to take into consideration the wants of their very own particular person pet and analysis whether or not a specific weight loss plan can be appropriate.

She mentioned that other than the kind of protein, issues like packaging and manufacturing strategies may also make a distinction. For instance, utilizing meat byproducts that may in any other case turn into waste would not drive elevated meat manufacturing the identical approach as utilizing human-grade meat.

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