5 myths it's a shame to believe in in 2017
Scientific myths that scientists and popularizers are already tired of talking about
There are several scientific myths that scientists and popularizers of science are tired of commenting on. Hundreds of hours have been spent exposing these beliefs, but they still live. We have selected five that occur frighteningly often in media, cinema or social networks. Of course, if you are our regular reader, you already know everything, but there are materials on the topic in the collection that you might have missed.
"Our brain only works at 10%"
Or by 4%, or by 5%. That's not true.
Olga Svarnik, neurophysiologist:
When we register brain activity, in particular the activity of nerve cells, we can calculate how many neurons we can meet when registering with a separate electrode. Knowing the sensitivity of the electrode, at what distance it "hears" neurons and that this electrode can sense neurons in a certain volume, we can determine from morphological sections that there are, for example, 1000 cells in this volume of the brain. But at the same time, when the electrode is in the brain, we hear that there are very few active neurons, just in the region of 5-10% or even less.
But such an understanding of the work of the brain is erroneous, because the registration of these neurons occurs at moments when an animal or a person performs some behavior, is engaged in some activity. If we are talking about a free-moving animal that is conscious and performs some kind of activity, it turns out that not all neurons take part in each separately performed type of activity, namely some percentage of their total number. A person cannot drive a car, read a book, play the piano and ski at the same time. Accordingly, at a particular moment in time, when a certain type of activity is performed, the activity of some neurons is recorded, at another moment — the activity of other neurons, and so on. Thus, the registration of a very small percentage of neurons involved in a certain type of activity does not mean that the brain does not work at 100%, but only works at 10% (in the sense of "poorly" working).
"HIV does not exist, it is a conspiracy of pharmaceutical companies"
That's not true.
Greg Towers, virologist:
HIV is the first human retrovirus. It stands for "human immunodeficiency virus". A retrovirus is a special type of virus. It has been known to exist in other species, but HIV is the first example of such a virus in humans. There are several types of it, the most common is called HIV-1. AIDS – acquired immunodeficiency syndrome is a disease caused by HIV.
HIV was first discovered in the early 1980s. Francoise Barre-Sinoussi and Luc Montagnier worked at the Pasteur Institute to describe a previously unknown viral infection. They received the Nobel Prize for this work.
Researchers learned to diagnose the presence of this virus, and it turned out that a large number of people were infected with it, but there was no treatment then. The virus spreads through sexual contact, that is, it is a sexually transmitted disease, as well as through blood preparations. You can also get infected, for example, through contact with blood.
By 2016, it is already possible to treat HIV with a cocktail of antiviral drugs, which in theory should prevent infection of new body cells. The patient can live a long enough life if he takes antiretroviral drugs. In the West, everything may be fine with treatment, but in resource-poor regions, such as Tropical Africa, where there is less money and it is more difficult to buy quite expensive antiretroviral drugs, this is a big problem. There are programs for the distribution of antiretroviral therapy so that every patient can get access to the necessary drugs.
"GMO foods are dangerous"
All transgenic plants undergo biosafety tests.
Dmitry Dorokhov, biologist:
One of the main reasons for the stratification of society and the protest movement against GMOs is that few people know what a transgenic plant is. There are still arguments at the level of "transgenic potatoes are harmful", "transgenic corn is harmful", but only transgenic corn has about 100 different lines with different signs.
Geneticists have the concept of a "transformational event" – a set of random events during which a genetic engineering design is introduced into the genome of a plant. As a result, a set of independent transformants is obtained – this is about 10,000 unique transgenic plants. Among these 10,000, only one genotype is selected that corresponds to the task, that is, it contains the trait that needs to be introduced, and the remaining signs practically do not differ from the original organism.
Each time, the genetically engineered DNA is embedded in different places of the genome, causing the uniqueness of the transformational event. If the site (site – any structural fragment of the genome) responsible for a particular function was disrupted during embedding, then such genotypes are discarded. If the site was sufficiently neutral and genetically engineered DNA is embedded in it, then the desired feature is obtained in this way, while preserving the existing beneficial properties of the original plant.
Each transgenic plant is subject to further state registration. All descendants of this plant will give rise to the line that will be registered. But before this happens, the necessary biosafety assessment procedures must be completed.
Biosafety tests include both studies of the interaction of genetically modified plants with the environment and the impact on human health. Only after such studies, an expert opinion is prepared with a proposal for state bodies to register or reject registration, indicating the reason. If a positive recommendation is prepared, a GMO monitoring plan is drawn up, which comes into force after a decision is made on the state registration of a transgenic organism.
"Global warming is an invention of corporations"
Or political elites, for example.
Nikolai Dronin, geographer:
Global warming is a trend increase in the average temperature on Earth over the past 100 years. It is calculated based on data from weather stations around the world. This calculation shows that the temperature is rising, and rising trendily, that is, it is a significant trend, and not just fluctuations around some long-term average temperature. In the end, since 1905, the temperature has increased by 0.86 degrees, which is a significant change.
Today, the world is dominated by the theory that the main cause of global warming is greenhouse gas emissions. In this regard, there is an unprecedented consensus in the scientific community: 97% of publications on climate change supported the theory that global warming is associated with greenhouse gas emissions, primarily CO2, by industry.
Calculations of temperature rise are carried out until the end of this century. The nearest threshold value is the excess of 450 million CO2 particles in the atmosphere. At the moment, the concentration of CO2 is about 400 million particles (for the first time this figure was recorded in February 2015). At 450 million, we will have an excess of the temperature threshold of 2 degrees. It is believed that up to this point we live in a familiar world, after which a change in the circulation system will begin. It is assumed that this will happen in 2040, and by 2100 there may be an excess of 4 or 5 degrees, which will actually change the entire climate system of the Earth.
"Nationality is in the genes"
That's not true. Genome analysis cannot reveal ethnicity.
Svetlana Borinskaya, geneticist:
Nationality (or ethnicity) is not sewn to the genes, this phenomenon is not biological, but cultural. The times when it was believed that the ethnos has a biological nature are gone. Ethnicity, as well as language, is not an innate trait – it is acquired (or not acquired) in communication with other people. The myth that "blood" or genes determine nationality (or any other signs formed under the influence of culture) is very dangerous. It has been used more than once to manipulate public consciousness, the consequences of which ranged from varying degrees of discrimination to genocide.
The family influences which ethnic group (or groups, if the parents have different ethnicity) a person will relate to. And of course, everyone gets not only language and upbringing from their parents, but also genes. Which parental genes the child will get is determined by the fusion of sperm and egg. It is at this moment that the individual's genome is formed – the totality of all hereditary information that, in interaction with the environment, determines the further development of the organism.
The processes of isolation of individual groups, interspersed with migrations and mixing of peoples, leave genetic "traces". If the number of marriages within a group exceeds the influx of genes from outside, then gene variants accumulate in such a group that distinguish it from its neighbors in terms of spectrum and frequency of occurrence.
Such differences were revealed in the study of population groups living in different regions of the world and having different ethnicity. Therefore, genome analysis can show which group a person's relatives and ancestors belong to – if these more or less distant relatives have already been studied by population geneticists and if they indicated their ethnicity during the study. But this analysis does not indicate the nationality or ethnicity of the owner of the analyzed genome – this nationality may be the same as that of his relatives (especially if they are close relatives), but it may be completely different.
Portal "Eternal youth" http://vechnayamolodost.ru
26.07.2017