Stingless bee queens endangered by regicide


This 2014 video says about itself:

Stingless bees fighting over a food source

The first clip shows the Brazilian stingless bee Scaptotrigona aff. depilis driving away four Melipona quadrifasciata foragers by lunging at and biting them. The second clip shows more intense aggression, as a Trigona hyalinata forager flings a M. quadrifasciata forager off the artificial flowers. These artificial flowers provide sugar water to the bees.

This video was filmed by Shawn Kessler at the Fazenda Aretuzina, São Simão-SP, Brazil as part of Elinor Lichtenberg’s PhD research.

From the University of Sussex in England:

Queen bees face increased chance of execution if they mate with two males rather than one

August 20, 2019

Queen stingless bees face an increased risk of being executed by worker bees if they mate with two males rather than one, according to new research by the University of Sussex and the University of São Paulo.

A colony may kill their queen because of the quality of offspring, according to the paper by Professor Francis Ratnieks, from the University of Sussex, along with colleagues Ayrton Vollet-Neto and Vera Imperatriz-Fonseca from the University of São Paulo, published in a leading evolutionary journal, the American Naturalist.

Professor of Apiculture Francis Ratnieks said: “By studying test colonies, we found that queen stingless bees will have an increased chance of being executed by the workers in their colony if they mate with two males instead of the one male they normally mate with.”

“The reasons for this are fairly complex but, in short, it’s due to the genetics of sex determination in bees and the risk of what’s known as ‘matched mating’.”

Queen stingless bees are closely related to honeybees and bumblebees but are only found in tropical countries like Brazil.

While a queen honeybee might mate with ten to twenty males, queen stingless bees normally only mate with one male. According to this new paper, that may be to reduce the chance of execution.

In bees whether an individual egg becomes a male or a female depends on a single genetic locus, known as the sex determination locus. Normal males arise from an unfertilized egg and have only one set of chromosomes, from the mother, and so only one sex allele.

If the egg is fertilized it will have two sets of chromosomes, one from the mother and one from the father. The two sex alleles can be different, in which case it is female, or the same, in which case it will be a diploid male — males who are a genetic dead end as they cannot reproduce and serve no useful function to the colony. What should have become a female worker, who will benefit the colony, is instead a useless diploid male.

When diploid males are produced, the worker bees in the colony can tell that things are not right and they generally execute the queen soon after adult diploid males emerge from their cells.

Diploid males are produced by ‘matched mating’ where the sex allele of a male the queen mates with is the same as one of the queen’s two, different, alleles. In a matched mating, 50% of the fertilized eggs from that male’s sperm will be diploid males.

If a queen bee mates with two males, although her chances of making a matched mating are doubled, the number of diploid males that could be produced decreases from 50% to 25%.

It turns out, however, that worker bees are just as likely to execute a queen who produces 25% diploid males as one who produces 50%.

Professor Ratnieks said: “If a queen mates with two males instead of one, her chance of being executed double. As a result, natural selection favours queens to mate with a single male in stingless bees.”

Interestingly, the researchers found that if a queen were to mate with four males, this would actually reduce her chance of being executed.

If a queen were to mate with four males and there was a matched mating, only 12.5% of the offspring would be diploid males. This low proportion is not enough to cause the workers to execute the queen.

The researchers point out that for stingless bees to evolve from single mating to multiple mating, with 4 or more males, there would need to be an intermediate stage of double mating. As double mating causes higher queen execution, natural selection does not allow this first stage to occur. Stingless bee queens seem to be stuck on single mating.

This study is about Scaptotrigona depilis.

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Belgian right-wingers: ‘Kill pro-climate girls, kill Jews’


This 17 August 2019 Dutch language video shows a reporter of Belgian Knack weekly. She interviews (drunk) far-right visitors of the Pukkelpop music festival. They shout: ‘Leftist rats, fuck off!’

On 15 August 2019, 18-year-old Belgian pro-climate activist Anuna De Wever had been invited to speak at Pukkelpop, one of many music festivals in summer in Belgium, to speak on the 20-27 Sepember global pro-climate strikes.

However, during her speech, a group of far-right men booed and heckled her, made obscene gestures, and threw alcohol at her.

The far-right men had flags depicting the Flemish lion.

The official flag of Flanders depicts a lion with red claws and red tongue. However, the men at the festival had flags with a black lion with black claws and black tongue. Wikipedia writes about that version:

It is not an official symbol. It was, however, used by the Flemish fighting alongside Nazi and SS troops [in World War II], and is as such also known as the collaboration [with Hitler] flag. It is today used by right[-wing] movements.

In this tweet, journalist Jeroen de Preter of Belgian Knack weekly writes about what happened next at Puppelpop. Translated:

About Pukkelpop and Anuna De Wever. Now, my daughter calling on the phone, very upset. After Anuna had been spotted at their tent, young men have stopped them from sleeping with death threats, thrown bottles full of urine at them and destroyed their party tent. Security is protecting them now.

The right-wingers also tore open several other tents as they thought Anuna De Wever might sleep there.

Security later reported they had banned the extreme right version of the Flemish flag at the festival. These flags had been distributed by the racist Vlaams Belang party.

Vlaams Belang youth branch

This photo shows members of the Vlaams Belang youth branch.

Vlaams Belang, like Donald Trump and other right-wingers deny climate change and support Big Oil.

Politicians of Vlaams Belang and also of the ‘moderate Flemish nationalist’ N-VA were very angry that the Pukkelpop organisation had banned the far-right version of the Flemish flag. They talked only about these flags, not what the men of these flags had done to teenage pro-climate girls.

Belgian (‘center-right’) daily De Gazet van Antwerpen, 20 August 2019, interviewed Robert Kaerts about what his 17-year old daughter went through at Pukkelpop. Kaerts is upset that politicians like Peter de Roover (N-VA) do not seem to care about what happened to those 17-year-old girls.

The far-rightists surrounded the girls’ tents all night. They tore open tents to find Anuna de Wever, one of them laid down on top of a girl, they shouted ‘green whores’, ‘kill Anuna’, ‘kill all Jews‘, they threw bottles full of urine, they tore up the party tent.

In spite of security protection, during the next night, there was again an attack on the party tent, and a bucket full of urine was put outside the girls’ tent. Robert Kaerts: ‘I cannot stop racking my brains about what would have happened if they would have succeeded in finding Anuna’.

See also here. And here.

Top Ten dinosaur, other fossil discoveries


This 19 August 2019 video is about what it considers the Top Ten dinosaur and other fossil discoveries.

They are, as it says:

10. T-Rex
In 2005, something that was previously thought to be impossible was found during an archaeological dig in Montana, and it would take 8 years before scientists could explain what had happened. The discovery was a leg fossil of an adolescent T-Rex, but inside it, there was some tissue that was described as being soft, transparent, and flexible.

9. Tail In Amber
With only fossils to go by, it’s difficult to know exactly what species looked like a long time ago, but a discovery in 2015 helped us get a much better idea! Within a lump of amber that was on sale at a market in Myanmar, was a perfectly preserved prehistoric tail- complete with feathers.

8. Homotherium
It had long been thought that Homotherium, a type of saber-toothed cat from Europe, had gone extinct about 300,000 years ago, but analysis of a discovery in 2000 forced researchers to rethink everything.

7. Brachylophosaurus
One of the rarest fossils found in recent times was of a Brachylophosaurus canadensis. It was found in a canyon wall in Montana in the year 2000, and it took a demolition crew to fully remove the 18-foot piece of stone from the cliff. Fossils of the 77 million-year-old duck-billed dinosaur are hardly ever found, but this one was even more special because its skin had also fossilized.

6. Hematite Tubes
The earth is believed to be around 4.55 billion years old, but a recent discovery has found that it wasn’t too long until the first signs of life began to emerge. Very few places on the planet have any rocks that are older than 3 billion years, but the places where some survive are the ideal hunting ground for ancient life.

5. Four-Legged Snake
The evolutionary history of snakes has long been of interest to researchers- specifically whether they emerged from the oceans without limbs or whether this was an adaptation that developed later on. Fossils to prove one way or another were proving to be elusive, but one discovery that was announced in 2015 changed all that.

4. Protoceratops and Velociraptor
One of the most stunning fossils ever to be found was discovered by a team that was looking at white sandstone cliffs in the Gobi desert in southern Mongolia. Dated to around 80 million years ago, it’s of two dinosaurs, a Velociraptor, and a Protoceratops, which were fighting each other when they were suddenly buried by a sand flow.

3. Baleen Whale
After originally having been found in 1978 and dismissed as unimportant, scientists returned to a fossil 30 years later and realized it was far more significant than was first thought. It had been discovered in a canyon in Palos Verdes in LA and is believed to be about 14 to 16 million years old.

2. Ichthyosaur
During the time of the dinosaurs, the oceans were just as dangerous as the land, and one of the most dominant predators to ever swim the seas was the Ichthyosaur. They evolved from land-based lizards who returned to the water around 250 million years ago, and the discovery in China of a fossil has given much clearer details of how they gave birth.

1. Nodosaur
In 2011, as a heavy machine operator dug up the ground at the Millenium mine in Alberta, he hit something that was noticeably harder than the surrounding rock. Strange colored lumps of rock started coming out and he realized he had found something unusual… something that turned out to be a very rare type of fossil.

Green sturgeon and salmon in California, USA


This June 2010 video from the USA says about itself:

Yurok Tribal Fisheries Program biologist Barry McCovey and technician Rocky Erickson capture and surgically implant an acoustic transmitter into a Green Sturgeon at the Klamath River in northern California.

From the University of California – Santa Cruz in the USA:

Shasta dam releases can be managed to benefit both salmon and sturgeon

August 20, 2019

Cold water released from Lake Shasta into the Sacramento River to benefit endangered salmon can be detrimental to young green sturgeon, a threatened species adapted to warmer water. But scientists at UC Santa Cruz and the National Marine Fisheries Service have found a way to minimize this apparent conflict through a water management strategy that benefits both species, while also meeting the needs of agricultural water users downstream.

Releases of cold water during the spring and summer create favorable spawning conditions in the Sacramento River for the endangered winter-run chinook salmon, which were cut off from their historical spawning grounds at higher elevations by the construction of Shasta Dam. Salmon eggs require cold water temperatures to survive, but juvenile green sturgeon need the lower flows and warmer temperatures typical of the main stem of the Sacramento River to grow and thrive.

The researchers used statistical modeling to see if there is an optimal management scenario that can meet the needs of both species along with those of downstream water users. Their results, published August 20 in the Journal of Applied Ecology, show that dam releases can be managed to achieve all three objectives in all but the most severe drought years.

“It’s a win-win-win here in the sense that we’re not giving up anything to get an improvement for the green sturgeon,” said Eric Palkovacs, associate professor of ecology and evolutionary biology at UC Santa Cruz and senior author of the paper. “Currently, the primary management objectives are keeping it cold for the salmon eggs and delivering enough water downstream. As a result, we’ve been refrigerating the river in regions where historically the green sturgeon have been spawning.”

First author Liam Zarri conducted the study for his UCSC master’s thesis, working with Palkovacs and coauthors Eric Danner and Miles Daniels at the National Marine Fisheries Service laboratory in Santa Cruz. Zarri found that discharge rates and water temperatures strongly influence the body condition of larval green sturgeon. In years with high discharges of cold water, egg survival for winter-run chinook salmon was high but the condition of juvenile green sturgeon was poor. In drought years, however, with low flows and warmer water, green sturgeon did well while salmon egg survival was low. The sturgeon larvae seem to be especially sensitive to high discharges, which affect their swimming ability and availability of prey.

The key to meeting the needs of both species, Zarri said, is that they spawn at slightly different times of the year. “We’re able to suggest a management scenario which uses the differential timing of spawning in these two species. When they overlap, our model gives us the ideal temperature and flow for when both species are present,” he said.

Zarri noted that the dam releases can draw either cold water from the bottom of the lake or warmer water from closer to the surface. Under the optimal management scenario proposed in the paper, low flows of warmer water can be released early in the season (April and May) when only green sturgeon are spawning and demand for water for agriculture has not yet ramped up. Late in the season (July to November), high flows of cold water can be released to benefit salmon and meet agricultural water needs.

The overlap period in June and early July, when both salmon and sturgeon are present in the part of the river most affected by the dam releases, is more complicated. That’s where the statistical modeling approach, which takes into account the needs of both species, provides the ideal conditions of temperature and water flow that dam managers can aim for to ensure that the river is not too warm for salmon or too cold and fast for sturgeon.

“Under the current management, there is quite a long period of cold water releases starting very early in the season before the chinook salmon have really started showing up in earnest. We’re saying that you can wait until the green sturgeon have matured and moved out of the system,” Palkovacs said. “That has a side benefit in drought years, when limiting those early releases saves water for later in the year when it’s more valuable, both for salmon and for downstream water demand.”

Palkovacs noted that other native species in the river, including spring and fall runs of salmon, are probably also being affected by the cold water releases. At this point, however, the researchers did not have enough information about other species to include them in their analysis.

This work was funded by NOAA and the U.S. Bureau of Reclamation.

Dragonflies and young house martins


Naardermeer marsh plants, 19 August 2019

On 19 August 2019, we went to the Naardermeer nature reserve.

Near the entrance, barn swallows flying. A great crested grebe swimming.

We see construction activity. Wildlife corridors are built underneath the railway; to save lives of grass snakes, moor frogs, otters, pine martens, etc.

On the footpath to the Muggenbult viewpoint, a male black-tailed skimmer dragonfly.

A grey heron.

Naardermeer marsh plants, near dragonfly, 19 August 2019

Along this bit of marsh, a beautiful green and blue dragonfly flies. An emperor dragonfly?

Naardermeer, on 19 August 2019

Naardermeer, 19 August 2019

Rowan berries.

On the footpath, a smallish red dragonfly.

A great cormorant flying.

Naardermeer, Muggenbult, 19 August 2019

As we arrive at the Muggenbult viewpoint, a coot couple and their chick swimming.

A male gadwall duck.

White and yellow water-lily flowers.

Two adult mute swans swimming with one youngster.

Naardermeer mute swan, 19 August 2019

A great crested grebe with two youngsters.

We walk back. On the visitors’ centre buildings, house martin nests, both artificial and built by the birds themselves. To both, parent house martins fly to feed their chicks.

Naardermeer, sundew, 19 August 2019

Close to entrance/exit of the nature reserve is a patch with carnivorous plants: sundew.