Tuesday, March 21, 2023

New eyes discovered in trilobites

by University of Cologne

New eyes discovered in trilobites
Compound and median eyes of trilobites. (a) Aulacopleura koninckii (Barrande, 1846), 
Silurian, Czech Republik, partly with shell preserved. (b) Holochroal compound eyes of 
(a). (c) Compound eye of Gerastos cuvieri (Steininger, 1831), Middle Devonian, Germany.
 (d) Schizochroal eye of Eldredgeops (Phacops) rana crassituberculata Stumm, 1953, 
Middle Devonian, USA. (e) A. koninckii, two larval stages. f) Upper specimen with location
 of the median eyes indicated. (g) Median eyes. (h, g) enlarged). (i) Cyclopyge sibilla 
Šnajdr, 1982, Ordovician, Morocco; 2 specimens, the lower larval. (j) Relevant specimen
 of (i). (k, j) Position of the median eyes indicated. (l) Median eyes in (j, k) indicated by 
white arrows. Yellow arrow: dorsal organ, comp. (h, i). Insert: dark structure in the fossil,
 which is not a median eye. m) Fully shelled glabella of A. koninckii (insert), no median 
eyes visible. (n1–4) Left median eye of C. sibilla (l), different contrasts. (o1–4) Median 
median eye of C. sibilla (l), different contrasts. (p1–4) right median eye of C. sibilla (l),
 different contrasts. 
Credit: Scientific Reports (2023). DOI: 10.1038/s41598-023-31089-7

Trilobites, prehistoric sea creatures, had so-called median eyes, single eyes on their foreheads, in addition to their compound eyes, research conducted by Dr. Brigitte Schoenemann at the University of Cologne's Institute of Zoology and Professor Dr. Euan Clarkson at the University of Edinburgh has now found out.

Such single eyes are found in all  and also in many relatives of the extinct . They are usually small cup eyes (ocelli), sometimes even equipped with lenses, and not unlike human eyes. These so-called median eyes are typical for all arthropods, but had not yet been discovered in trilobites despite 150 years of research.

The scientists assume that these eyes were characteristic of the larval stage of the animals. The single eyes were located under a transparent layer of the carapace, which became opaque during the fossilization process. Both circumstances contributed to the ocelli not being discovered until now. The researchers also detected median eyes in other, approximately 500-million-year-old arthropods.

Depending on their evolutionary status, these arthropods had different numbers of median eyes. In future, the number and shape of the single eyes will help to classify the evolutionary status of individual  species. The researchers have published their findings in Scientific Reports.

Arthropods usually have two types of eyes:  and the so-called 'median eyes' or middle eyes. The latter are located in the middle of the forehead between the compound eyes. Only trilobites, an important group of arthropods in the Paleozoic, did not seem to have had median eyes.

This was the assumption until Schoenemann and Clarkson examined a specimen of the  Aulacopleura koninckii in which part of the head had been scraped off. They found three almost identically shaped dark, inconspicuous and tiny oval spots of the same size at the front of the head. These three structures are parallel to each other and fan out slightly on the underside. All three spots are characterized by a smooth, clear outline and a uniform, dark brownish color.

"This clear, regular appearance distinguishes this structure from random formations produced by decay or fossilization, and corresponds to the expected relics of simple median eyes equipped with a pigment layer. Even if it is a single find, it supports the assumption that trilobites originally had median eyes," Schoenemann explained.

In the trilobite Cyclopyge sibilla, which lived in the free ocean, the researchers also found three cup-shaped median eyes on the so-called glabella, the region in the middle of the forehead between the large compound eyes, which even apparently had a lens not unsimilar to , and were thus clearly more differentiated and probably much more efficient than those of the bottom-dwelling trilobite Aulacopleura.

In their article, the researchers also consider why the median eyes of trilobites have escaped detection until now: "These eyes are present in trilobites at the larval stage, but lie beneath what is probably a thin, transparent carapace (cuticle), which becomes opaque during fossilization. Both explain why they have remained undiscovered until now," she added.

Thus, the researchers have solved the mystery of missing middle eyes in trilobites. Schoenemann said, "These cup eyes are derived from those of the primitive stump-footed animals, so-called velvet worms, small worm-like animals with legs. The original number of median eyes is 2, which present-day, very conservative arachnids still have. In phylogenetic, very primitive arthropods (e.g. Cindarella eucalla from the lower Cambrian of China) there are 4, modern animals, such as insects and crustaceans, have only 3. With the help of the number of median eyes in an arthropod, we now have an important tool to determine its position in the evolutionary tree."

More information: Brigitte Schoenemann et al, The median eyes of trilobites, Scientific Reports (2023). DOI: 10.1038/s41598-023-31089-7

Journal information: Scientific Reports 


Provided by University of Cologne 

Primordial 'hyper-eye' discovered

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Calls for ban on light-polluting mass satellite groups like Elon Musk’s Starlink

Astronomers urge people to stand up to ‘big light’ industry amid unchecked brightening of night sky

Nicola Davis
@NicolaKSDavis
Mon 20 Mar 2023 

A ban on megaconstellations of low-altitude satellites – arrays such as Elon Musk’s Starlink – should be considered, astronomers have said, in an effort to reduce light pollution and preserve our ability to study the skies.

In a series of papers and opinion pieces published in the journal Nature Astronomy, scientists have raised the alarm about the brightening night sky, with one team of experts calling for scientists to stand up to “big light” as they have to other fields, such as big tobacco and big oil, and bring in regulation.

For megaconstellations of low-altitude satellites, they write, this could mean a veto.

“On the scales of immediate or long-term benefits and harm to society, and despite the popularity of satellite megaconstellations, we must not reject the possibility of banning them. On the contrary, we believe that the impacts and risks are too high for this possibility to be ruled out,” they write.

The team say that it is unlikely that bodies contributing to light pollution – be it from ground-based LEDs or other lamps, or low-altitude satellites – will regulate themselves.

“Every time some health or environmental issue arises and starts to be addressed in the scientific literature, the ‘machine of doubt’ is put into action by the polluters to stop, or at least delay by years or decades, the adoption of countermeasures and rules to protect human health and the environment,” write Fabio Falchi, from the Light Pollution Science and Technology Institute in Italy, and co-authors in a comment piece.


Light pollution rapidly reducing number of stars visible to naked eye, study finds

As a result, the team have called for action.

“In my opinion there should be a cap limit on the total number of satellites in low orbits, and their number is probably already too high,” Falchi said, with the team writing that caps should also be introduced for artificial light at night.

According to an accompanying perspective piece, megaconstellations have more than doubled the number of functional satellites in low Earth orbit since early 2019, with a vast number of launches planned in the coming years.

But experts say this has come at a cost: the illumination of the artificial satellites and associated space junk by the sun has increased night sky brightness.


“We are witnessing a dramatic, fundamental and perhaps semi-permanent transformation of the night sky without historical precedent and with limited oversight,” writes John Barentine of Dark Sky Consulting and colleagues.

According the authors, one concern is that faint astrophysical signals will become increasingly hard to detect due to increasing night sky brightness.


End ‘colonial’ approach to space exploration, scientists urge


“An example with distinct and potentially severe social consequences is the detection of near-Earth objects that represent a high risk of colliding with our planet,” they write. In addition, the team note that an increase in “noise” can lead to a loss of efficiency and hence a greater financial burden for research facilities due to an increase in the time needed to collect and combine data.

Satellites trails in astronomical images are another problem, while there is also a concern about the impact of increasing night sky brightness on biological systems.

Then there is the impact on the public, who may find it harder to see the Milky Way, familiar constellations, weak aurorae and faint meteors.

Overall, the scientists suggest the stakes are too high for inaction.

“For the general public there is the possibility to lose the natural sight of a perfect natural starry sky, everywhere on Earth,” said Falchi.
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Calgary·Analysis

Why Canada likely won't need any more big new oil pipelines after Trans Mountain

With slowing oil production growth, developers would be hesitant to pitch projects

Kyle Bakx · CBC News · 

The long saga over the Trans Mountain pipeline expansion is nearing an end as the project enters its final phase. With oil production growth slowing in western Canada, some industry experts believe this could be Canada’s last big oil pipeline project.

Construction of the Trans Mountain expansion project is set to wrap up later this year, and it's likely the last new oil export pipeline the country will ever need.

The pipeline has faced many obstacles over the years, including protests, court challenges and massive cost overruns. Last week, the cost of the federally owned project was updated to more than $30 billion.

Over the last decade, several other high-profile pipeline proposals have faltered, but the Trans Mountain expansion is more than 80 per cent built, and oil is expected to start moving in early 2024.

As oil production growth slows in Alberta, some in the industry suspect there won't be a need for any more new oil export pipelines.

"I think we'll be good," Alex Pourbaix, president and CEO of Cenovus Energy, said in an interview.

"I don't think we're going to see another large-scale liquid pipeline coming forward, certainly in the next decade."

.
Cenovus Energy CEO Alex Pourbaix, right, shown at the Global Energy Show in Calgary in June 2022, says there is less need for new oil pipelines as production growth slows. (Jeff McIntosh/The Canadian Press)

Protests, political battles, court challenges

When the Trans Mountain expansion was first pitched more than a decade ago, the proposal seemed relatively straightforward, since the project would twin an existing pipeline largely along the same route. In addition, the pipeline wouldn't cross multiple borders, running from Alberta to British Columbia.

For the first few years after the project was announced in 2012, it received very little attention — especially as the spotlight was on other pipeline proposals, such as Northern Gateway, Energy East and Keystone XL.

Protesters hold a black banner with orange letters that reads: 'Climate Leaders Don't Build Pipelines.'
Protesters opposed to the Trans Mountain pipeline expansion project arrive at a park just below a construction site in Burnaby, B.C., in March 2021. (Darryl Dyck/The Canadian Press)

Still, as those projects faltered and the Trans Mountain expansion neared construction, the scrutiny quickly followed.

There were protests from Indigenous communities and environmental advocates; political battles between Alberta and B.C.; regulator and court challenges; and many other obstacles that caused more delays, uncertainty and expenses.

The Trans Mountain project was bought by the federal government for $4.5 billion in 2018, after previous owner Kinder Morgan Canada Ltd. — which was acquired by Pembina Pipeline Corp. in December 2019 — threatened to scrap the pipeline's planned expansion project in the face of environmental opposition, legal challenges and political risk.

The cost of the project has escalated over the years because of several factors, including global inflation and supply chain challenges, severe floods in British Columbia, route changes, challenging terrain and security expenses.

Pipelines close to capacity

Despite all of the problems, experts say the economic case for the pipeline remains, since it will allow Canadian oil to reach the coast and fetch a better price than shipping it to the United States, where the majority of Canadian oil flows.

The industry also needs another export channel, since existing pipelines are running out of space.

"We're pretty close," said, Kevin Birn, a vice-president with S&P Global Commodity Insights in Calgary, who expects the Trans Mountain expansion to be full of oil when it's up and running.

A worker wearing a yellow hard hat and a safety vest stands on a pile of dirt at a construction site near a crane.
A worker looks on as construction continues on the Trans Mountain pipeline expansion project in Burnaby, B.C., in March 2021. The project was purchased by the federal government for $4.5 billion in 2018, in the face of environmental opposition, legal challenges and political risk. (Darryl Dyck/The Canadian Press)

"Overall, through the back end of this decade, we see the entire western Canadian system — even including some expansions and optimizations that haven't happened — running north of 90 per cent utilization. And that's well into the 2030s with the completion of TMX."

Birn said he also doubts that the country will see the construction of any more large oil pipelines — not only because there won't be enough oil production to justify the need, but because all of the problems with the Trans Mountain expansion would make a pipeline developer cautious and hesitant to build a big project in Canada.

Meanwhile, for the main opponents of Trans Mountain, there is some solace, considering how much has changed in Canada over the last decade in terms of natural resources development, environmental policy and Indigenous rights.

"They kind of lost the battle but won the war," said George Hoberg, a professor at the School of Public Policy and Global Affairs at the University of British Columbia in Vancouver.

He documented the pipeline and several other projects in his book The Resistance Dilemma: Place-Based Movements and the Climate Crisis.

The federal government was able to leverage its support for Trans Mountain to get Alberta to join the Pan-Canadian Framework on Clean Growth and Climate Change, Hoberg said, while Indigenous groups have gained more rights after Ottawa adopted the United Nations Declaration on the Rights of Indigenous Peoples.

Heavy machinery moves pipelines during the night.
Construction on the Trans Mountain expansion project is shown near Hope, B.C., in October 2021. The existing pipeline, which runs for 1,150 kilometres, carries 300,000 barrels of oil per day. The expansion will raise the daily output to 890,000 barrels. (Jonathan Hayward/The Canadian Press)

Even without new oil export pipelines proposed again in the country, experts say there will still be conflict over the continued operation of existing oil infrastructure, as well as the development of new natural gas, carbon dioxide and hydrogen pipelines. The construction of new electricity transmission lines will cause similar controversy, Hoberg said.

"They are pipelines for electrons, and they have the same features as a pipeline in the sense that they are long, linear infrastructure," he said.

Ownership comes next

As construction of the Trans Mountain expansion nears the finish line, the focus will soon turn to the project's ownership. The federal Liberal government has said it would sell the pipeline but only after it's certain the project will be completed.

For a few years, some Indigenous-led groups have been preparing to make bids.

"TMX is very polarizing because of the protection of the environment," Stephen Buffalo, president and CEO of the Indian Resource Council, said, noting the risk of a spill.

If Indigenous groups have an ownership stake in the project, there is more accountability and involvement by local communities to ensure environmental protection, he said.

The existing Trans Mountain pipeline, which runs for 1,150 kilometres, carries 300,000 barrels of oil per day and is the only pipeline system transporting oil from Alberta to the West Coast.

The expansion will raise the daily output to 890,000 barrels.

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 Why do some men dislike Justin Trudeau so much?

Men who strongly dislike Justin Trudeau say it's because they think he's fake, arrogant, divisive, and feminine.
DELIBERATELY CONFUSING FEMINISM WITH FEMININE

David Coletto
20 hr ago

A few weeks ago, Susan Delacourt of the Toronto Star asked if I had any data that might help explain why men disliked Justin Trudeau so much. My firm Abacus Data and the Toronto Star recently announced a polling partnership and this was the sort of assignment - digging deeper into topics - that we wanted to do together.

So I set out to try and answer this question through a nationally representative online survey of 4,000 Canadian adults conducted from February 9 to 18, 2023. I asked several questions I hoped would provide some evidence to explain this phenomenon.

inFocus with David Coletto is a reader-supported publication. To receive new posts and support my work, consider becoming a free or paid subscriber.

Susan wrote a smart piece about the results, but I wanted to ensure the full results and my thoughts were here, on the record.

It also follows up with some commentary I shared with Jennifer Ditchburn in a story she wrote for the Canadian Press back in 2013.

“I think there is a subtle attempt not necessarily to question Justin Trudeau’s masculinity but to at least make him appear less masculine,” said David Coletto, a Canadian market researcher and CEO of Abacus Data.

Coletto says recent polling shows Trudeau does just as well with men as with women, something that would worry the Conservatives.

“I think (the ads) are meant to weaken his standing, particularly among middle-aged men, who are really the core of the Conservative government’s coalition, so they’re trying to shore that up ... the idea that this guy’s not a man’s man, and maybe therefore not worthy of our vote,” said Coletto.

So here’s what I’m seeing in the public opinion data:

Men do have a more negative impression of the Prime Minister than women, and the dislike is much more intense.

Men are 10 points more likely than women to have a “very negative” impression of Justin Trudeau. 36% of men have a very negative impression compared with 26% of women. Overall, 52% of men have a negative view compared with 44% of women.




Since Justin Trudeau and the Liberals were elected in 2015, men have always held more negative views than women. And over time while negative impressions have increased, so too has the gender gap in them.

But it is worth noting that a sizeable portion of men didn’t always hate Trudeau. When he was first elected, only 10% had a very negative view. Today, it has more than tripled to 36% (up 26 points). Women’s impressions of Trudeau have also become more negative, but they haven’t risen as much - up 18 points over the same period.




Who are the men who really don’t like Trudeau?

These men tend to be slightly older, more likely to live in Alberta and Saskatchewan, less likely to have a university education, more likely to be white, and more rural.

 They also tend to be less happy and much less trusting of news organizations. Household incomes are the same as others and they are as likely to be fathers as those who aren’t as unhappy with Trudeau as they are.



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