The ancestors of giraffes were originally short-necked, but in order to eat the leaves of tall trees, they often craned their necks. Repeating this action continuously, the neck becomes longer as time goes by, and eventually they evolved into the current giraffe.
The above method of evolution is the “acquired inheritance” proposed by the French biologist Jean Baptiste Lamarck around 1801, also known as “Lamarckian evolution”. It is believed that the traits of organisms will change naturally. Can be passed on to offspring. But today’s mainstream evolutionary theory is based on the natural selection theory proposed by Darwin later. Unlike what Lamarck said, Darwin believes that the changes that occur in the offspring of organisms are caused by random mutations in genes, and have nothing to do with the changes in the traits of the organism.
But recently, biologists have discovered that the external environment and biological behavior sometimes do have an impact on genetics. Pollution, smoking, stress and diet may cause some genes in our body to be expressed, or cause some other genes to be dormant. Other creatures have similar phenomena. In some cases, this change in gene expression can be passed on from generation to generation. For example, when a mouse smells a certain smell, it will receive continuous electric shocks. It will be very afraid of the smell, and this fear will even be passed on to its grandchildren. This is because the environment has changed the gene expression of mice and passed on to offspring. This phenomenon is epigenetic.
Epigenetics seems to be a Lamarckian evolution. So, compared with genetic inheritance, how much role does epigenetics play in biological inheritance? Or is it just a short-lived phenomenon that has no effect on the overall biological evolution? Can epigenetics finally make Lamarckian theory “turn over”? These problems are already one of the important unsolved problems in the field of biology.
Effectiveness of acupuncture
The use of acupuncture to relieve pain has become popular all over the world. But putting a needle into your skin can really cure the pain? Or is it just a placebo? Felicity Bishop, a health psychologist at the University of Southampton in the United Kingdom, is confident: “I am willing to bet that acupuncture can relieve pain better than a placebo.” She also bet that in a carefully designed double-blind experiment, acupuncture The effect of the treatment is much better than the effect of “fake needle” treatment. “Fake needle” refers to a specially designed needle that can make the tester think that the needle pierced the skin, but in fact it did not pierce the skin.
But at present, people have not been able to design a double-blind experiment that makes everyone unable to fault. But in any case, acupuncture seems to be inseparable from the placebo effect. After all, the acupuncturist needs to communicate closely with the patient, which may have a positive psychological comfort to the patient. Acupuncturists also often advise patients to change their lifestyles to relieve pain. Bishop also admits that you cannot ignore these obvious placebo effects. Maybe acupuncture is really effective, but it may be difficult to find evidence to convince everyone.
We extract the nucleus from an animal and implant it into an egg from which the nucleus has been removed, so that we can replicate the animal exactly like the original. This is the somatic cell cloning technology. With this cloning method, we have cloned cows, mice, chickens and sheep in the past few decades. So, will humans be next?
Some people believe that cloning can “resurrect” a lost child, and that human cloning can also provide transplanted organs for terminally ill people. But from a moral perspective, human cloning is clearly a minefield. In addition, cloning itself has many technical problems. For example, the failure rate of cloning is extremely high, and the health of the clone is difficult to guarantee. The famous cloned sheep Dolly is the only cloned sheep to succeed in 277 attempts. Although Dolly was normal when she was born, she later developed osteoarthritis and died of lung disease at the age of 6.
However, Dolly’s luck may have been too bad, because the few sheep cloned afterwards all lived healthy to adulthood. In any case, if humans are involved, cloning will face more technical problems. For example, in primates, the spindle protein close to the nucleus plays a vital role in cell division. When the nucleus of the egg is removed, these proteins are often destroyed, thereby affecting its division.
At present, many countries have banned human cloning experiments for the purpose of reproduction, but there are still many controversies about human cloning experiments for the purpose of treatment. So, will human clones appear in the next 10 years? Alison Murdoch is one of the few scientists in the UK who has the right to study cloned human embryos. She believes: “As a scientist, I can’t say that there is absolutely none, but I estimate that the possibility is close to zero.”
Hallucinogen obtains drug marketing authorization
More and more evidences show that hallucinogens can help treat mental illnesses such as stress disorder and depression. So, while providing hallucinogens to people in need of treatment, how to prevent it from being abused by the crowd?
This dilemma makes it difficult for scientists to study hallucinogenic substances such as MDMA (ecstasy) and psilocybin (the hallucinogenic ingredient contained in psilocybin). Obtaining and storing these drugs requires cumbersome procedures, expensive authorization fees, strict security measures, and so on. However, things are moving towards a better side. In 2016, researchers from Imperial College London conducted the first clinical trial of psilocybin to treat depression. Although the hope is very slim, it is possible that hallucinogens will be approved for drug marketing within the next 10 years.
Commercial nuclear fusion reactor
Although many countries in the world have made a lot of progress in controllable nuclear fusion research, researchers have been repeating words like this for decades: We still need 30 to 40 years from commercial nuclear fusion reactors.
The International Thermonuclear Fusion Experimental Reactor (ITER) built in southern France represents the greatest hope for mankind to tame the power of the sun. This reactor funded by various countries is a magnetic confinement fusion reactor. Its principle is as follows. In a donut-shaped container, a magnetic field is used to confine high-temperature plasma composed of nuclei such as deuterium and tritium and free electrons in a limited volume to promote them A nuclear fusion reaction occurs. However, ITER’s research progress is 11 years behind the original plan and is now expected to be officially launched in 2027. Although it costs 13 billion euros, it is only a demonstration model and cannot generate enough electricity to connect to the grid. It seems that it is a difficult goal to make the electricity generated by nuclear fusion reach millions of households within 10 years.
Unless, ITER’s competitors can achieve better results. Wendelstein 7-X, located in the northern part of Germany, is a nuclear fusion reactor with a different design from ITER. Its container is not shaped like a donut, but like a twist. It costs 1 billion euros and plans to achieve 30 minutes of continuous operation in 2021, but it is only a demonstration model.
The prospects of countless smaller nuclear fusion research projects are equally doubtful. Many researchers said that lack of funding is one of the important reasons for the slow progress of research. It seems that the world needs to heavily fund this project.