Tuesday, July 31, 2018

Normal bees and killer bees



turning normal bees into killer bees
Africanized bees, commonly known as "killer bees", are much more aggressive than their European counterparts. Now, a team of researchers have examined the changes in neuropeptides that take place in the brains of these bees during their aggressive behavior and have shown that they can turn normal bees into 'killer' by injecting certain peptides.

Only a few neuropeptides make the difference between a honey bee and another that has an irritable need to wipe out everything that moves.

To discover what it is that makes Africanized "killer bees" so hostile, the State scientists at the University of São Paulo (Brazil) compared their neurochemistry with that of their more docile relatives and found that it is mostly due to a surprisingly simple chemical change.

The reputation of killer bees is well deserved. Its venom is no more lethal than average honey bees and they are even a little smaller, but they are incredibly aggressive, and it does not take much provocation to incite a swarm of these bees to become a furious and poignant pain machine.



The more hostile an animal is, the more caution you have to have

These bad-tempered striped insects appeared in the late 1950s, after Brazilian beekeepers imported an African variety of Apis mellifera scutellata in order to increase honey production. It seems that the bees did not understand the fine print very well and ended up paying for the honey bees.

Since then, these aggressive hybrids have spread to northern California and remain a legitimate threat. Several hundred people have lost their lives due to their implacable twinge. And is that this subspecies is also extremely sensitive to the presence of humans. They usually attack the eyes and the face, and the only thing that can be done before them is to run away.

But what happens in your brain to act in this way?

To get to the bottom of the mystery, the researchers of this last study had to collect a sample of killer bees (something not without danger). Using a rather curious trick they managed to catch them to observe their tiny brains.

The comparison of the full range of brain proteins from two bee samples using mass spectral imaging revealed a clear, but simple difference.

One of the suspected proteins was called Apis mellifera Allatostatins A, a neuroprotein that is already known to play a key role in the learning and memory of bees, as well as in their overall development.

The other group of proteins, described as tachykinin-related peptides, seems to influence sensory processing.

In aggressive hybrids, these two groups of neuropeptides had been cut into shorter proteins, and found in different groups of brain tissue called neuropiles.

To verify that these proteins were significant in the transformation of the behavior of the bee, the scientists injected in the brain of a group of non-aggressive bees truncated forms of these neuropeptides.

As expected, the bees did not seem very happy when they woke up, because having modified their brain chemistry they had also become killer bees.

However, it is still unknown why the size and distribution of these neuropeptides lead to such aggressive behavior. Learning more about the cascade of effects that these proteins have on the nervous system of a bee could tell us more about the development of the nervous systems of bees, as well as those of insects in general.


Saturday, July 21, 2018

Curiosities about polar bears



The lion is par excellence the king of the jungle, but if we change the scenery and drastically lower temperatures, the polar bear becomes, without any doubt, the new and legitimate monarch.

These amazing creatures inhabit the waters covered by the Arctic ice, extending from Canada, Norway or Denmark, to some areas of Russia and even, to a lesser extent, in Iceland. This causes that the idea that the polar bears unfold with great ease in adverse conditions and extremely dangerous for any other type of living being is reaffirmed.

It is estimated that there are currently between 22,000 and 32,000 copies worldwide, indices that, due to their progressive decline, have awakened for years the concern of biologists and scientists. In fact, this species has become the reference for the health status of ecosystems. Unfortunately, the extreme situation of polar bears is a powerful indicator of the lack of effective environmental policies worldwide.

For more than twenty years, polar bears have been forced (and increasingly) to travel long distances during the summer periods in search of frozen areas. Precisely, it is the ice that depends on obtaining food from these animals, because it is what allows them to hunt. The rise of temperatures delays the solidification of the water and therefore, delay (and shorten) the feeding period of the bears. Unfortunately, it is increasingly common to find these animals in a serious state of malnutrition. The most prone to this are the females with puppies that inhabit the areas further south of their range.

Organizations such as the Oceanic Administration of the USA have carried out different research on the environmental impact of the melting of the Arctic plates. The latest results have been alarming, since 2016 recorded the smallest sea ice surface in the last 37 years.

Despite the difficulties, the polar bear is still one of the most impressive creatures on the planet, as its characteristics make it an icon of the animal kingdom. In the next gallery we show you everything you need to know about this vulnerable, but powerful species.


Evolution

The polar bear (Ursus maritimus) evolved from a population of brown bears during the Pleistocene. Some research suggests that this process began about 38 million years ago, when a large group of bears separated and adapted to new living conditions.


800 kilos

It is the largest terrestrial animal. It measures up to 3 meters from the snout at the end of the tail, and weighs up to 800 kilograms (the male). However, they have relatively small heads.


Family of 3

The polar bears have two young per litter after a gestation period of 6.5 to 9 months. The young remain with the mother for 2 or 3 years. The rest of the time, they are solitary animals.


Tireless travelers

The polar bear can travel up to 1000 kilometers in the changing seasons, when the ice melts or freezes, either walking on the ice or swimming. His nose is so sharp that he can smell a seal 32 kilometers away.


Black under a white coat

Under the white fur, the polar bear's skin is black, which helps him absorb the sun's rays. In addition, it has a thick layer of grease to withstand polar temperatures. Its double fur coat repels water and, thanks to its white color, helps it to camouflage itself.


At 37 degrees

The polar bears, in addition, maintain an average temperature of 37 degrees. The reason why they endure extreme temperatures is that in addition to their thick and hard skin layer, these animals have a thick layer of extra fat. This is the cause of its thermoregulation. However, that same layer is what causes them to have a rapid overheating and can not withstand high temperatures.


Lazy

Polar bears are inactive most of the time (66.6% of their lives). Overheating is one of the main factors by which this species moves at a low speed and usually lie down to rest.


Playing live more

The polar bears that play live longer, enjoy better health and have more offspring, according to a recent study by the ethologist Robert Fagan of the University of Alaska.


A great smell

One of the most developed senses of the polar bear is its smell. It is so sharp that you can smell the seal of a seal more than 30 kilometers away, something very useful considering the difficulties to find food. In addition, it is very important to identify any type of danger that may lurk around you.



Feeding

They can eat up to 30 kilos of food in the same day. Its main source of food are seals. They have 42 sharp teeth, which allow them to easily devour their prey. These pieces are longer than those that the brown bear has in its mouth.


They dive

Sometimes, when stalking their prey, the polar bears are submerged in the water thanks to the adaptations of their legs. This activity is also performed to find algae, cleanse or reduce body temperature. It is estimated that they can remain submerged for 2 minutes at depths between 3 and 5 meters.


Always clean

This species is extremely clean, because after hunting and devour their prey, always spend time to remove with water and snow the remains of the animal in your body. Researchers suggest that, because they are so sensitive to smell, they are uncomfortable with the smell and need to remove it immediately.


Satellite tracking

WWF and Canon have developed the online tool (Polar Bear Tracker) that allows us to follow their migratory movements in the archipelago of Svalbard, Norway, the Sea of ​​Beaufort, Alaska, the Bay of Hudson and Canada. The use of collars with satellite devices helps to closely monitor their movements, expand knowledge of their habits and know how they are affecting the impacts of climate change.


In danger

The polar bear is listed as a vulnerable species in the Red List of Endangered Species of the International Union for Conservation of Nature. According to reports from the World Wildlife Fund, these creatures could disappear during the next century if the destruction of their ecosystem is not stopped.

Monday, July 16, 2018

Giraffes surprise scientists again



So far, the theory that the size of groups of wild animals is larger when the risk of them being attacked by their direct enemies, the predators, is generally accepted. This is basically due to the fact that the more members that make up the collective, the more protected they will be and the more easily they will be able to detect and warn of a danger. However, a new study (the first to investigate this group tendency) of the University of Bristol (England) has shown that this assumption was not entirely true, or at least not in the case of giraffes.

This study has been based on observing how the grouping of these animals differs from the rest in factors such as the risk of predation, the type of habitat and the characteristics of the individuals that haunt. The type of habitat had remarkable effects on the size of the group. However, the main change was reflected in the behavior of adult females, who tended to be in smaller groups when they were in procreation and had offspring. This last data belies another popular belief that giraffes were thought to form large groups for the community care of their offspring.

The researcher and doctoral student Zoe Muller says that "these data are surprising and reflect how little we know about giraffes, even in the most basic aspects of life. This research adds another important piece to the puzzle of understanding how giraffes live in nature. "


Extraordinary animals in danger of extinction

It is estimated that giraffe populations have decreased by approximately 40% in the last three decades. Among the survivors, it is thought that there are just under 98,000 individuals left in freedom. These figures have led to the inclusion of the species in the Red List of Endangered Species of the International Union for Conservation in Nature and has been classified as 'vulnerable'. Experts see this as a valuable step in recognizing the seriousness of their extinction, and understanding the threats and challenges they face in nature.

"Giraffes are an endangered species that suffer a constant decline in Africa, and this research highlights how incredibly misunderstood they are, and we can only manage and conserve giraffe populations effectively if we understand their behavior and ecology, which is what we are just beginning to do, "says Muller.

Another of the popular ideas of the society is that giraffes abound in Africa and for that reason, they point to it as an indisputable icon of the continent. However, the figures reveal a very different reality, since its decline is progressive and accelerated.

The next step in this investigation is to expand the project to different areas of Africa, since this study has been carried out only in the eastern part. According to Muller, more research is needed to see if the same effects are observed in other groups of giraffes. The extracted results could be used to understand how the habitat alteration and other environmental and social variables can help the conservation of the populations of this species.

Sunday, July 8, 2018

Good news for mountain gorillas


If Dian Fossey, the popular zoologist author of the book "Gorillas in the Mist" was alive, surely today would have many reasons to be happy. And, according to the data of the last census, the population of mountain gorillas (Gorilla beringei beringei) has doubled in the last three decades.



"This is one of those very rare conservation news," explains Martha Robbins, an expert gorilla researcher at the Max Planck Institute for Evolutionary Anthropology. "Despite the poaching, the degradation of their habitat and the civil war, the population of gorillas in the Virunga mountains has doubled."

To estimate the number of individuals of this endangered species, a field campaign was conducted between 2015 and 2016. The teams kicked more than 2,000 kilometers through the Virunga Mountains looking for tracks and other signs of the presence of gorillas. In addition, genetic analyzes were made that took more than 18 months to complete and studied more than a thousand fecal samples, determining that there are at least 186 gorillas not used to human contact. The researchers estimate that the current total population of mountain gorillas in the Virunga volcanoes surpasses the six hundred specimens that would be distributed in 41 social groups, and 14 of them would be solitary males. To this figure we must add the approximately 400 individuals that live in the Impenetrable National Park of Bwindi, in Uganda, for which we speak of a total of more than 1,000 gorillas.


More accurate census methods

The last census had been made in 2010 and estimated a population of 480 gorillas. The current figure represents an increase of 26% in a period of only six years, which means an annual growth rate of 3.8%. Although it is true that the study methods are now much more precise, so it is possible that in previous censuses had estimated "down", the truth is that there has been real growth in the population, as reported by the Max Institute Planck.

"The genetic analysis of fecal samples allows us to count gorillas without having to observe them," explains Linda Vigilant, director of the genetics laboratory specializing in primatology in Leipzig. "It will also allow us to obtain more information about how social groups are formed and the changes that occur in them over time."



"This result is the result of the efforts made by the governments of Rwanda, Uganda and the Democratic Republic of the Congo to keep the great apes in danger of extinction and, in particular, the hard work of the staff working in the field," says Robbins . "The spectacular increase in the population of gorillas shows that the efforts made in terms of sustainable tourism, veterinary work and community projects can have a positive impact on one of our closest living relatives."

Much remains to be done in the Virunga mountains, for example, to improve the security of forest agents and tourists. Only in the last ten months have twelve workers been killed in the park, and in the last incident two British tourists were abducted. Due to this, the Virunga National Park is currently closed to the public to improve its security protocols and, according to The Guardian, will not open its doors until next year.

Sunday, July 1, 2018

DNA from ancient animals will help trace cultural exchanges in China

Chinese archaeologists plan to use DNA from ancient domestic animals to establish their importance in cultural exchanges along the Silk Road in China.

Experts from Jilin University, located in the city of Changchun, capital of Jilin Province, northeast China, will collect samples of remains of domestic animals that have been discovered at various sites along the Silk Road. , to perform analysis of the entire genome.



Domesticated animals contributed to trade and trade as a stable resource of protein and energy.

Cai Dawei, a professor at the university, said the research would be a new vision of the development of the Silk Road.

The trip of an imperial emissary named Zhang Qian to the western regions around the year 140 a. C. is generally considered to be the beginning of cultural exchanges between East and West, but recent archaeological finds show that such activities actually began in prehistoric times. According to Cai, at the end of the Paleolithic they would already be taking place.

Among the first examples of exchanges are the arrival in the East of bronze smelting and domesticated animals, such as horses and cattle, and the introduction in the West of millet and decorated pottery.



The researchers, who have the support of China's National Social Science Fund and the cooperation of archaeologists from Central Asia and Europe, hope to complete their studies in 2022.