The birds that live around Lake Constance are disappearing

According to a new study, the number of birds living around Lake Constance is in sharp decline. The results of the study show that the lake region has lost 120,000 breeding copies over the past 30 years.

Six of the most common bird species living around the lake have declined dramatically in number and only two of these species have increased. For example, the population of domestic sparrows has decreased by 50% since 1980 while swallows have decreased by 70%.

The partridge, which was once a very common bird in the land around the lake region, has instead completely disappeared as has the owl. They are also suffering from species that usually survive almost everywhere, such as finches, robins and blackbirds.

These are “really shocking figures,” as Hans-Günther Bauer, a researcher at the Max Planck Institute for Animal Behaviour, says, and they would have been even stronger if the count had started before 1980 as the decline began decades earlier. If we were to make a projection into the future, the decline would therefore have to be even greater.

The problem of habitat is the biggest one: bird populations are shrinking rapidly in those areas and are being used intensively by humans, especially in agriculture. Another reason is the scarcity of food: insects are also decreasing around the region and even the latter are disappearing by human hand.

Links/Sources:

https://www.mpg.de/13849147/dramatic-decline-of-birds-at-lake-constance

Australian birds are losing much of their habitat

Hundreds of Australian bird species are losing their habitat, especially in South-East Australia. A new study published in Conservation Biology has analyzed various threatened and unthreatened bird species and found that they have lost almost two-thirds of their natural habitats.

The same study differs from the others because it also takes into account non-threatened species. Jeremy Simmonds, the study’s head, himself, specifies how all too often only threatened birds are highlighted or researched.

In fact, even the most common and most widespread species can be endangered and can be important for the environment, as the researcher himself specifies: “Common species play a vital role in controlling pests and pollination of insects and their decline through loss of habitat has implications for the health of ecosystems.”

Researchers analyzed changes in the habitats of 447 different Australian bird species since 1750. Needless to say, the greatest negative changes have occurred in those areas where there has been greater deforestation.

The same researcher calculates that for every hectare of forest felled 180 different species of birds are affected in terms of habitat loss.

Links/Sources:

https://conbio.onlinelibrary.wiley.com/doi/abs/10.1111/cobi.13331

Fossil worm from 550 million years ago discovered

A team of researchers from Virginia Tech analyzed ancient fossils of a small animal species. A discovery that is considered, as defined in the press release, “the most convincing sign of ancient animal mobility.”

Yilingia spiciformis

The researchers classified Yilingia spiciformis (Yiling is the name of the Chinese city where the discovery of the fossil was made). Fossil remains were found in various layers of rock by researchers from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences.

The study, published in Nature, describes this animal that dates back to the period of ediacaran. We are talking about a period prior to the age of the dinosaurs. The Yilingia spiciformis was a sort of worm about 10 cm long and about 1.3 cm wide. It could drag its body from the muddy bottom of the ocean to make its way to the mainland. It rested along the road and left long traces. It had 50 body segments, a back and a stomach, and a head and a tail.

Important discovery

This discovery is especially important because, as Shuhai Xiao, professor of Geosciences at Virginia Tech, states, it shows that mobile animals evolved at least 550 million years ago.

The characteristic of mobility that is considered fundamental also for the colonization of the mainland by life, is found in the group of animals called “bilaterans,” a vast group of which we humans are also part and which basically indicates the animals symmetrical bilaterally.

“Their ability to shape the face of the planet is ultimately linked to the origin of animal motility,” says the same researcher in the press release.

The very ability of animals to move intentionally probably marks one of the first decision-making processes among the animals themselves: the paths they took suggest an effort to move to or away from something, a characteristic perhaps dictated by a central nervous system that was beginning to become as sophisticated as that of today’s animals.

“When and how it evolved, animal locomotion defines an important geological and evolutionary context of anthropogenic impact on the Earth’s surface,” Xiao reports.

The research was published in Nature.

Links/Sources:

https://vtnews.vt.edu/articles/2019/09/Science-Shuhai_Xiao_half_billion_animal_trail.html

https://www.nature.com/articles/s41586-019-1522-7

Snake uses top of head to breathe underwater

A group of researchers found that the blue bandaged sea snake (Hydrophis cyanocinctus) uses a complex blood vessel system placed on top of the head to absorb oxygen from the surrounding water when it is immersed. That is a discovery that surprised the researchers themselves.

It is a modified cephalic vascular network (MCVN) that provides an amount of oxygen to the brain that can be considered as complementary during the dive, as Alessandro Palci, an evolutionary researcher at the University of Flinders visiting the University of Alberta, Canada, specifies.

“Basically we have discovered that this sea snake uses the top of its head as a gill to breathe underwater,” reports the researcher to be even clearer. The Hydrophis cyanocinctus is a poisonous snake that lives in the warm tropical waters near the coasts of the Southeast Asia region.

It is not a system that allows snakes to breathe completely underwater: sooner or later they must re-emerge to breathe in the amount of oxygen needed by the brain. What they can get from the water is only a complementary part to allow the snakes to stay a little longer immersed.

However, among the vertebrates breathing from the air, this species of snake can be considered as one of the most “aquatic” in absolute.

Links/Sources:

https://royalsocietypublishing.org/doi/10.1098/rsos.191099

https://en.wikipedia.org/wiki/Hydrophis_cyanocinctus

Each Filipino student will have to plant 10 trees if they want to graduate.

This is an idea that can certainly be considered as innovative comes from the Philippines to combat deforestation and therefore also the reduction of carbon dioxide in the air. According to a new law already approved by the legislative council of the Philippine Parliament, each student before graduating will have to prove that they have planted at least 10 trees.

According to calculations provided by experts to the Philippine parliament itself, if this bill is approved by the president who has yet to sign it, there will be an increase in the number of trees of about 172 million units per year. In a single generation, naturally counting the level of reproduction of the plants themselves, experts estimate an increase of 525 billion new trees.

The Philippine Parliament, as well as large sections of the population, is particularly concerned about the environment as the islands are among the most deforested areas in the world. It is thought that the forest-covered territories in the Philippines have decreased from 70% to 20% in just a few years. This will not only bring problems in the medium and long term but has already caused several problems such as landslides and floods in areas most prone to geological instability.

Students will not be able to plant trees wherever they want. The authorities will indicate the areas in which the new trees will have to be planted, such as residential areas, industrial zones, spaces in front of schools, hospitals, universities, etc. The authorities will indicate the areas in which the new trees will have to be planted.

Links/Sources:

http://congress.gov.ph/legisdocs/first_17/CR01007.pdf

Alzheimer’s: “hunger hormone” linked to memory according to study

A group of researchers found links between ghrelin, defined as “hunger hormone,” in the brain and memory loss associated with Alzheimer’s disease.

Researchers analyzed brain tissue samples from patients with deceased Alzheimer’s and performed experiments on mice. The study was published in Science Translational Medicine.

Grelin is called “hunger hormone” because it has the task of sending signals to the brain to balance the energy supply and thus also the ingestion of new food. It plays a strong role in appetite but, as other studies have shown, it is also linked to learning and memory.

In a healthy hippocampus, the area of the brain crucial for learning and memory, ghrelin binds to certain dopamine receptors to form a protein complex that maintains a balanced level of communication between brain cells and therefore also memory itself.

In this study, researchers found that in the hippocampus beta amyloid binds to ghrelin receptors and this blocks the latter’s ability to bind to dopamine receptors.

Heng Du, associate professor at the University of Texas and one of the authors of the study, comments on the results of the research: “Our hypothesis is that this dissociation between the receptors of ghrelin and dopamine may be what is affecting cognition in Alzheimer’s patients. Since the brain loses the function of ghrelin receptors due to beta amyloid, the body tries to compensate by increasing ghrelin production and the number of ghrelin receptors. But the amyloid prevents the functioning of the receptors.”

The same researcher adds that, based on these results, Alzheimer’s itself could be linked to the resistance of ghrelin.

Links/Sources:

https://www.utdallas.edu/news/research/hunger-hormone-memory-alzheimers-2019/

https://stm.sciencemag.org/content/11/505/eaav6278

Squirrels listen to birds’ verses to understand the presence of predators

An interesting discovery was made by a group of researchers, which concerns the relationship between squirrels and birds. According to the researchers, who published their work on PLOS, the grey squirrels feel reassured by the “chatter” of the nearby singing birds, verses that in a way makes them feel safer.

Birds usually “sing” to communicate various simple basic signals, such as the absence of danger or sharing their position. Obviously squirrels have learned these same lines to understand in turn that there is no imminent threat. Researchers have analyzed in particular 54 oriental grey squirrels (Sciurus carolinensis) present in various green areas of Ohio.

They then alternately reproduced recordings to simulate a threat, specifically the cry of a red-tailed falcon (Buteo jamaicensis) and the verses of the birds themselves. This park is a common predator for both species. At the same time, they monitored the behavior of the squirrels.

When listening to the recorded verse of the hawk, all the squirrels showed the typical behavior they adopt in the presence of predators, such as immobility, the look up or the flight. However, when the researchers also started recording the different birds, the squirrels themselves performed fewer “vigilance” behaviors, basically showing that they felt a little more “relaxed.”

This is the demonstration that squirrels themselves use the birds’ verses to understand the presence and imminence of danger.

The research was carried out by Marie V. Lilly, Emma C. Lucore and Keith A. Tarvin.

Links/Sources:

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0221279

Super monosex shrimps created in the laboratory to prevent the spread of parasites

Super monosex shrimps created in the laboratory that could reduce the spread of an important parasite as well as increase the results of aquaculture: this is the purpose that is being carried out by a group of researchers from the Ben-Gurion University of Negev (BGU).

In a study published in Scientific Reports, the group talks about a “super shrimp” that produces only female offspring. This is precisely the reason for the increase in results in terms of aquaculture.
This is an interesting biotechnological result that could have important implications also in the economic field.

The researchers, by transplanting androgenic gland cells, were able to cause complete sex reversal in females of Macrobrachium rosenbergii shrimps that have become functional males. Through the latter, an all-female progeny without the Z chromosome can be produced.

Tom Levy is one of the researchers involved in the project together with Professor Amir Sagi. Levy himself speaks of the usefulness of this research also with regard to the fight against parasites: “Shrimps serve as effective biocontrol agents against parasite-carrying snails. And because we can now use monosex shrimps, which do not reproduce, it reduces the risk of the shrimp becoming an invasive species.”

The snails that shrimp feed on, in fact, can carry parasites that cause schistosomiasis, a disease that can have bad effects on the human urogenital system.

The results have also been achieved without the use of hormones or genetic modifications.

Links/Sources:

https://in.bgu.ac.il/en/pages/news/super_shrimp.aspx

https://www.nature.com/articles/s41598-019-47509-6

New study solves an old mystery of the tyrannosaurus

A new study, produced by researchers from various American universities, has analyzed the two large holes in the skull of Tyrannosaurus Rex and comes to unexpected conclusions.

This area of the head of these ravenous dinosaurs, called the back of time window, has been a mystery for a long time. According to the main theory developed by paleontologists, these holes were full of muscles that helped the movement of the jaw.

However, Casey Holliday, professor of anatomy at the School of Medicine at the University of Missuori, had some doubts and decided to analyze again this strange anatomical conformation that characterizes the tyrannosaurs many other species of dinosaurs and arcosaurs. It all started when the researcher found strange the anatomical conformation proposed by the theory: the muscle would rise from the jaw, turn a 90° and then pass along the top of the skull.

Using the thermal imaging technique and examining alligators from a Florida zoo, Holliday and colleagues believe they have solved the mystery: the holes in the head serve as a “cross-current circulatory system,” as Kent Vliet, a researcher at the Department of Biology at the University of Florida, also employed in the study, says. This area of the skull was used to keep the temperatures of the skull lower, a sort of “internal thermostat” made by a particular vascular structure combined with adipose tissue.

Studying alligators, in fact, the researchers noted that when there were periods with lower temperatures, the thermography analysis showed large hot spots in the area of these holes and this indicated an increase in temperature. However, during the same day the holes appeared darker, as if they had been closed to keep the area cooler.

“Using the anatomy and physiology of today’s animals, we can show that we can reverse the first assumptions about the anatomy of this part of the skull of Tyrannosaurus Rex,” says Larry Witmer, professor of anatomy at the University of Ohio, another author of the study.

Links/Sources:

https://onlinelibrary.wiley.com/doi/abs/10.1002/ar.24218

Researchers analyze walnut shells under a microscope and discover a new cell

A group of researchers discovered the secret of nuts and their shells, which are sometimes very difficult to break. The study appeared in Advanced Science.

Walnuts have an extremely strong shell made from layers of cells that in turn have very hard walls and separation fibers that form a polygonal pattern. The researchers have in particular analyzed the shells of classic walnuts, those produced by plants of the genus Juglans, whose shell is made of very dense tissue in which the same forms that the cells create are difficult to recognize even with a high degree of magnification.

The researchers isolated the single cells of these shells thanks to a particular organic polymer and examined them with the microscopes. They identified a new type of cell, never classified before, which they called the polylobate sclereid cell (polylobate sclereid).

It is a particular cell that has irregular lobes and contours sometimes concave, sometimes convex. The result is a scheme in which each cell has 14 other cells close together in a very complex scheme which, however, makes the shell very strong, almost woody, and resistant to traction.

The results obtained could be of help in creating an equally light and resistant material based on the same type of structure.

Links/Sources:

https://www.sciencemag.org/news/2019/09/why-walnuts-are-such-tough-nuts-crack