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How Insects’ Ancestors Learned to Fly





insects flying

(Credit: MakroBetz/Shutterstock)

Before they flew, winged insects had to learn to glide. Scientists say they’ve puzzled out the evolutionary path that gave insects wings, settling what had been a longstanding debate in the field. Using genetic techniques to peer back in time, researchers found that the winged insects of today once had stiff, fixed forewings used for descending.

“Winged insects… were the first group of animals to conquer the air and the evolution of insect wings can be considered as one of the most important events in the history of animals,” said Benjamin Wipfler, an evolutionary biologist at Friedrich-Schiller University in Jena, Germany, who led the new research.  

The discovery means insect wings did not evolve in an aquatic environment as scientists once thought.

Enduring Debate

Whether winged insects evolved on land or in the water is a “major unresolved question,” according to Wipfler and his colleagues. Many researchers assert the ancestors of modern winged insect species lived in the water because immature mayflies and dragonflies —  two early diverging groups of winged bugs — have an aquatic lifestyle. But the fossil record doesn’t provide any clear answers and until now no one had put together the kind of analysis necessary to settle the dispute.

Wipfler and an international team of scientists wanted to close the debate. Using the largest dataset ever constructed for this purpose, the researchers scrutinized the protein-coding sequences of more than 3,000 genes from over 100 living insect species. The analysis allowed the scientists to create a family tree for winged insects that identifies which groups are most closely related to each other. This allowed them to work backwards in time to see what the common ancestors of these species were. The team also traced the evolution of over 100 traits related to insects’ body structures, habitats, diets and social behaviors.

Flight Control

Together, the analyses revealed the last common ancestor of winged insects today was terrestrial, Wipfler and his collaborators report today in the journal The Proceedings of the National Academy of Sciences. Based on the analysis the team built a virtual model of what this land-dwelling forebearer to flying insects looked like.

“Our study now shows [the evolution of insect wings] did not happen in an aquatic habitat,” Wipfler said. Previous theories that posited wings grew from sails or underwater buoyancy organs can be excluded based on their work, he continued.

Although contemporary winged insects use their wings for flying, that probably wasn’t the case for this terrestrial ancestor, the scientists say. While it had something resembling wings, they were likely much shorter, and critically, immobile, meaning the appendages would be useless for powering flight. Instead, Wipfler and colleagues think the ancestor used its wings to make controlled, gliding descents from high points. It’s similar to some theories of how flight developed among mammals and other creatures — appendages that allowed for short glides eventually morphed into wings.

Little by little, insects gained the ability to take to the skies under their own power — likely the first time any creature on Earth did so.


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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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