The problems with US presidential candidate Biden


This 4 February 2020 video from the USA says about itself:

The Case Against Joe Biden: Former VP’s Long Career Shows a Recurring Theme of “Appeasing the Right”

Following his Super Tuesday wins, we look closely at the record of former Vice President Joe Biden, from his central role in supporting the Iraq War to expanding the so-called war on drugs. We speak with Branko Marcetic, the author of “Yesterday’s Man: The Case Against Joe Biden.” Biden’s approach to politics is based on “appeasing the right” and “taking the platform of his Republican opponent and trying to make it his own”, Marcetic says.

United States billionaire Bloomberg ends presidential campaign


This 4 March 2020 video from the USA says about itself:

Panel Reacts to Bloomberg suspending his 2020 campaign, endorsing Biden

So, Bloomberg‘s bad Super Tuesday election results mean that he threw hundreds of millions of dollars propaganda money down the drain.

This 4 March 2020 video from the USA is called The Empire Strikes Back On Super Tuesday & Bloomberg Drops Out.

Establishment scared of Sanders victory as Bloomberg drops out of race: here.

AIDES: BLOOMBERG CAMPAIGN ISN’T KEEPING PROMISES Staffers for Mike Bloomberg’s failed presidential campaign say they were laid off despite promises that they would be employed through the November election. Hundreds of the aides received emails Monday saying they were terminated, but could reapply for positions in battleground states where some campaign offices would remain open. [HuffPost]

Shrimps’, insects’ brains are similar


This 9 October 2017 video says about itself:

Insect like Brain Region Found in Crustacean Brain

Mushroom bodies are the iconic learning and memory centers of insects. No previously described crustacean possesses a mushroom body as defined by strict morphological criteria although crustacean centers called hemiellipsoid bodies, which serve functions in sensory integration, have been viewed as evolutionarily convergent with mushroom bodies. Here, using key identifiers to characterize neural arrangements, we demonstrate insect-like mushroom bodies in stomatopod crustaceans (mantis shrimps).

More than any other crustacean taxon, mantis shrimps display sophisticated behaviors relating to predation, spatial memory, and visual recognition comparable to those of insects. However, neuroanatomy-based cladistics suggesting close phylogenetic proximity of insects and stomatopod crustaceans conflicts with genomic evidence showing hexapods closely related to simple crustaceans called remipedes. We discuss whether corresponding anatomical phenotypes described here reflect the cerebral morphology of a common ancestor of Pancrustacea or an extraordinary example of convergent evolution.

From the University of Arizona in the USA:

The brains of shrimps and insects are more alike than we thought

March 3, 2020

New research shows that crustaceans such as shrimps, lobsters and crabs have more in common with their insect relatives than previously thought — when it comes to the structure of their brains.

Both insects and crustaceans possess mushroom-shaped brain structures known in insects to be required for learning, memory and possibly negotiating complex, three-dimensional environments, according to the study, led by University of Arizona neuroscientist Nicholas Strausfeld.

The research, published in the open-access journal eLife, challenges a widely held belief in the scientific community that these brain structures — called “mushroom bodies” — are conspicuously absent from crustacean brains.

In 2017, Strausfeld’s team reported a detailed analysis of mushroom bodies discovered in the brain of the mantis shrimp, Squilla mantis. In the current paper, the group provides evidence that neuro-anatomical features that define mushroom bodies — at one time thought to be an evolutionary feature proprietary to insects — are present across crustaceans, a group that includes more than 50,000 species.

Crustaceans and insects are known to descend from a common ancestor that lived about a half billion years ago and has long been extinct.

“The mushroom body is an incredibly ancient, fundamental brain structure,” said Strausfeld, Regents Professor of neuroscience and director of the University of Arizona’s Center for Insect Science. “When you look across the arthropods as a group, it’s everywhere.”

In addition to insects and crustaceans, other arthropods include arachnids, such as scorpions and spiders, and myriapods, such as millipedes and centipedes.

Characterized by their external skeletons and jointed appendages, arthropods make up the most species-rich group of animals known, populating almost every conceivable habitat. About 480 million years ago, the arthropod family tree split, with one lineage producing the arachnids and another the mandibulates. The second group split again to provide the lineage leading to modern crustaceans, including shrimps and lobsters, and six-legged creatures, including insects — the most diverse group of arthropods living today.

Decades of research have untangled arthropods’ evolutionary relationships using morphological, molecular and genetic data, as well as evidence from the structure of their brains.

Mushroom bodies in the brain have been shown to be the central processing units where sensory input converges. Vision, smell, taste and touch all are integrated here, as studies on honeybees have shown. Arranged in pairs, each mushroom body consists of a column-like portion, called the lobe, capped by a dome-like structure, called the calyx, where neurons that relay information sent from the animal’s sensory organs converge. This information is passed to neurons that supply thousands of intersecting nerve fibers in the lobes that are essential for computing and storing memories.

Recent research by other scientists has also shown that those circuits interact with other brain centers in strengthening or reducing the importance of a recollection as the animal gathers experiences from its environment.

“The mushroom bodies contain networks where interesting associations are being made that give rise to memory,” Strausfeld said. “It’s how the animal makes sense of its environment.”

A more evolutionarily “modern” group of crustaceans called Reptantia, which includes many lobsters and crabs, do indeed appear to have brain centers that don’t look at all like the insect mushroom body. This, the authors suggest, helped create the misconception crustaceans lack the structures altogether.

Brain analysis of crustaceans has revealed that while the mushroom bodies found in crustaceans appear more diverse than those of insects, their defining neuroanatomical and molecular elements are all there.

Using crustacean brain samples, the researchers applied tagged antibodies that act like probes, homing in on and highlighting proteins that have been shown to be essential for learning and memory in fruit flies. Sensitive tissue-staining techniques further enabled visualization of mushroom bodies’ intricate architecture.

“We know of several proteins that are necessary for the establishment of learning and memory in fruit flies,” Strausfeld said, “and if you use antibodies that detect those proteins across insect species, the mushroom bodies light up every time.”

Using this method revealed that the same proteins are not unique to insects; they show up in the brains of other arthropods, including centipedes, millipedes and some arachnids. Even vertebrates, including humans, have them in a brain structure called the hippocampus, a known center for memory and learning.

“Corresponding brain centers — the mushroom body in arthropods, marine worms, flatworms and, possibly, the hippocampus of vertebrates — appear to have a very ancient origin in the evolution of animal life,” Strausfeld said.

So why do the most commonly studied crustaceans have mushroom bodies that can appear so drastically different from their insect counterparts? Strausfeld and his co-authors have a theory: Crustacean species that inhabit environments that demand knowledge about elaborate, three-dimensional areas are precisely the ones whose mushroom bodies most closely resemble those in insects, a group that has also mastered the three-dimensional world by evolving to fly.

“We don’t think that’s a coincidence,” Strausfeld says. “We propose that the complexity of inhabiting a three-dimensional world may demand special neural networks that allow a sophisticated level of cognition for negotiating that space in three dimensions.”

Lobsters and crabs, on the other hand, spend their lives confined mostly to the seafloor, which may explain why they’ve historically been said to lack mushroom bodies.

“At the risk of offending colleagues who are partial to crabs and lobsters: I view many of these as flat-world inhabitants,” Strausfeld says. “Future studies will be able to tell us which are smarter: the reef-dwelling mantis shrimp, a top predator, or the reclusive lobster.”

Strausfeld co-authored the paper with two of his former students — Gabriella Wolff, now a post-doctoral fellow at the University of Washington, and Marcel Sayre, now a doctoral student at Lund University in Sweden. They hope that the study of mushroom bodies will further help in resolving how brains may have evolved and what environmental conditions shaped that process.

This research moves us closer to answering the ultimate question,” Strausfeld says. “We want to know: What was the earliest brain like?”

What Finnish damselflies eat, new research


This 2018 video from Ferguson, Missouri in the USA is called Damselflies Mating and Laying Eggs.

From the University of Turku in Finland:

Dragonflies are efficient predators

They consume hundreds of thousands of insects in a small area

March 3, 2020

A study led by the University of Turku, Finland, has found that small, fiercely predatory damselflies catch and eat hundreds of thousands of insects during a single summer — in an area surrounding just a single pond. In terms of weight, this equates to a total prey mass of just under a kilo. Dragonflies mostly catch different kinds of midges, but also large numbers of other insects.

Who keeps numbers of insects in check during the summer? This has been debated for some time, but a clear answer has remained elusive, as it has been difficult to monitor the numbers consumed by different insect predators. A new study now sheds light on the role of dragonflies that occur in large numbers.

Even in just a small area, populations of matchstick-sized damselflies that whiz around, consume hundreds and thousands of insects. Although the numbers of prey species individuals hatching in the area is as much as one hundred times the quantities being consumed by the damselflies, the quantity consumed is nevertheless significant because there are many other predators also preying on the same prey species.

The results of the novel study were obtained by combining multiple scientific methods. The prey species of the dragonflies and their relative quantities were assessed by examining prey DNA extracted from the faeces of damselflies, using a method known as metabarcoding. Population estimates of dragonflies were also obtained.

Chironomids are damselflies’ favourite food

Dragonflies are among the apex predators of the insect world and are considered to be responsible for regulating the numbers of many other insect species. During the period studied, the insect species consumed the most by the damselflies were different chironomids.

– In the 12-hectare area we studied, the catch mass for the four species of dragonflies was about 900 grams, equivalent to about 700,000 medium-sized midges. This equated to around 1% of the total mass of the midge populations in the area. This amount should not, however, be disregarded, as damselflies are by no means the only predators of midges and other insects. The area we are studying has an enormous number of other predators, including twenty other species of dragonfly, as well as birds and bats, explains Docent of Molecular Ecology Eero Vesterinen from the Biodiversity Unit of the University of Turku, who was responsible for the project’s DNA analyses.

We investigated the numbers of dragonflies by marking them with a series of numbers on their wings, releasing them and then catching them again. By comparing the numbers of marked and unmarked dragonflies caught, we were able to estimate the total number of individuals in the area. The numbers of insects consumed, meanwhile, were estimated by covering certain areas with tent-like hatching traps and counting how many insects accumulated in them over a particular surface area, explains Senior Researcher Kari Kaunisto from the Biodiversity Unit of the University of Turku, who led the study.

Dragonflies have always fascinated people, as they are impressive insects and effective predators. Dragonflies are also particularly at risk because they are apex predators in natural ecosystems.

– In this study, we focused on four small but locally abundant damselfly species from among the 62 dragonfly species found in Finland, Vesterinen adds.

The species studied were the common blue damselfly (Enallagma cyathigerum), the northern damselfly (Coenagrion hastulatum), the Irish damselfly (Coenagrion lunulatum), and the variable damselfly (Coenagrion pulchellum).

New information on natural food web functions

Understanding the functioning of the food webs is particularly important now, when natural diversity is diminishing at an accelerating rate.

– For the first time, our study examined the intensity of insect hunting in relation to the total number of insects being preyed on. The collapse of insect populations reduces the amount of food available to dragonflies, but it has not been possible to assess the impacts of predation by dragonflies without this accurate information on food chains, says Kaunisto.

Professor Tomas Roslin from the Swedish University of Agricultural Sciences, who participated in the study, is really excited about the new approach and the interesting results of the study.

– By combining several methods, the research reveals the overall impact of predation in nature. We succeeded in revealing both the wide range of insects preyed on by dragonflies and the significance of predation in relation to both individual prey species as well as the community as a whole, Roslin exclaims.