If today, all human normal body temperatures are up 1 degree, to 38 degrees Celsius, then the earth, nature and human society will change what happens? Similarly, if the average human body temperature are reduced by 10 degrees, so the tropical is not already suitable for human survival? This is an open brain hole problem, because the human body temperature is the number of long-term environmental changes and the results of human co-evolution, but this still does not prevent us as far as possible from a scientific point of view to explore.
Does the person’s body temperature be 37 ° C? Accurate, 37 ° C is the average temperature in the oral cavity at rest at about 12 o’clock in the healthy adult, the theory was first proposed by 19th century German physicist Carl Wunderlich. In 1992, the British National Health Service System (NHS) conducted a further survey of 148 people’s body temperature, the average body temperature of about 36.8 ℃, and 36.1 ℃ (97 ℉) to 37.2 ℃ (99 ° F) between the free fluctuations. (123) In addition, many studies have found that individual differences in people, age differences (A), different parts of the trunk (B), different times of day (C) and some Inflammation and other disease response (D) and so will produce fine-tuning of the individual temperature.
The relationship between human body temperature and the environment First assume that: the normal temperature of human beings have increased once
. For the earth, because the energy provided by the sun does not change, and all the energy flowing in the biosphere comes from the producers of fixed solar energy, this part of the energy flowing through the ecosystem eventually dissipated in the form of heat, regression To the environment.
Even if the human body temperature rises, the individual intake of food may increase (but the plant fixed the total solar energy unchanged), while he dissipated into the environment heat also increased. Thus
the total energy for the earth should not change
. For nature, the “human” species belongs to the top of the food chain. Elevated body temperature means that the intracellular
becomes more intense (entropy increases after the protein and other macromolecules are more active), so it appears that the basal metabolism does improve. This means that humans need to obtain more food, of course, also produce more calories (on the basis of the same population base).
The result of more human metabolic activity is – global warming !
However, in the end how warm it?
This calculation, if the body of basic metabolism increased by 13%, each person’s carbon dioxide emissions will increase 7.6 tons / year, while the global population (7.5 billion) of carbon dioxide emissions increased by 57 billion Ton / year So much of the greenhouse effect brought about by the carbon dioxide can not be underestimated, please refer to the specific greenhouse effect on the natural environment. For human society, mankind will be forced to grow more food crops because of the increase in basal metabolism and the increase in carbon emissions, or as Seth Wynes says. To reduce the loss of energy in the energy transfer chain or to maintain the basic energy supply at the expense of the “family planning” population. Of course, the wisdom of mankind is infinite, so that self-sufficiency is estimated.
Second, the assumption that the normal body temperature of humans is reduced by 10 degrees
. For the hypothesis that “if human average body temperature drops by 10 ° C”, it is understood that ambient temperatures rise by 10 ° C when exploring human adaptation to the environment. The following left is the human body under normal circumstances on the environmental temperature tolerance, we can imagine the ambient temperature increased by 10 ℃ situation. This ambient temperature isIs not already suitable for human survival?
Let’s take an interview with the Indian classmates at the table – as in the right news headlines, where the maximum temperature in India has reached 50 ° C in the real world, resulting in 500 deaths due to high temperatures; And then increased 10 ℃, it is difficult to imagine how people maintain normal life.
If the average human body temperature drops by 10 ℃, with the global “relative warming” intensified, part of the “hot dead “High temperature areas (such as 40 ℃ high temperature in Shanghai, etc.) will indeed no longer suitable for human habitation .
In contrast, the meow star’s body temperature is actually higher than the normal human body, about 38-39.5 ℃. Therefore, according to a conservative estimate of meow stars will likely increase the invasion, and further occupation of the Earth. Of course, the above problem is purely open, because the temperature of the human body is the result of interaction with the environment, can not suddenly rise or decrease.
The impact of human body temperature changes on their own In the regulation of human body temperature, the subject also overlooked a very important issue is that
changes in human body temperature will produce our own What impact
In fact, changes in basal metabolism are only one aspect, and some serious scientific research confirmed that the truth is far more exciting than we thought –
1. Increased body temperature, able to infect human fungi to reduce?
This is one of the few research opinions around the topic “Why do we need to maintain body temperature of 36.8 ° C”.
Some scientists believe that the relatively high body temperature can make large
most fungi on our body discouraged. One of the co-authors of the paper, Professor Arturo Casadevall, has confirmed that 6% of the fungi lose the infected host at a temperature of between 1 and 4 ° C between 27 ° C and 40 ° C ability. This is why tens of thousands of fungi can infect reptiles and amphibians and other thermostat animals, but can threaten humans and other mammals, but only hundreds of species.
However, the obvious drawback to improving body temperature is that humans need to gain calories from more foods to maintain body temperature. In this study published in the journal “mBio”, Arturo Casadevall and Aviv Bergman studied the relationship between the temperature of organisms at temperatures between 30 ° C and 40 ° C and the increase in resistance to fungal / food demand.
The authors also suggest that elevated body temperature can also bring other benefits, such as maintaining the activity of the body, so that mammals can escape from the claws of large hunters. After the extinction of dinosaurs, it is possible to resist the high body temperature of fungal infections that make mammals the dominant organism on Earth.
However, there are still many controversies surrounding the theory. First of all, fungal infection of human effects is actually unknown
. Surely some fungi are indeed pathogenic, but most of the fungi are harmless to the human body, so whether the mammals really just to resist the fungus and at the body temperature to be further research.
In addition, if more food is needed to maintain body temperature, warm animals will have to increase foraging activities, thereby extending the time to exposure to predation. Therefore, for the animal to improve the benefits and disadvantages of body temperature, living environment considerations is an indispensable part.
2. Lower body temperature, extended life expectancy?
The more recent study shows that hypothermia can be extended
In 2006, American scholar Bruno Conti published this article in the academic journal “Science”. They specifically express a protein called uncouplingprotein2 in a neural cell near the hypothalamic preoptic region of the mouse thermoregulatory region, which can cause localized temperature rise by the release of heat. Body temperature adjustment center will be sensitive to capture this change, and mistakenly believe that the body temperature, and thus start the body temperature regulation reaction to heat.
BrunoConti et al. Established a mouse model with a body temperature of 0.3-0.6 ° C lower than that of normal mice. The male mice with low body temperature had 89 days longer than normal male mice and 112 days for females. To know that the average life expectancy of only 2-3 years of mice, which is equivalent to 100 days to extend the life of one-tenth, and this change is only the body temperature is reduced by less than 1 ℃.
The red line represents the hypothermia mouse, the black line represents the normal mouse, the horizontal axis represents the age, the vertical axis represents the survival rate, the left is the female mouse, the right is the male. The upward shift of the red line means that the same age of low-temperature mice have a higher survival rate. 3. Body temperature is inversely proportional to subjective time. This experimental conclusion, such as relativity, was published in the Experimental Psychology Quarterly as early as 1995. John Wearden et al., University of Kiel, UK, studied the perception of time in the context of changes in body temperature between 1927 and 1993.
They allow subjects in different body temperature states to record the “they think” 100 seconds in a stopwatch, and found that the change in subjective time is negatively correlated with body temperature changes, ie when the body temperature is higher than 37 ° C , Subjects often feel the passage of time becomes faster (subjective time shorter); body temperature below 37 ℃, then the opposite (subjective time longer).
Researchers speculate that it is likely that high temperatures cause some hormones to release, leading to more nervous transduction
1. http: //www.webmd.boots.com/a-to-z-guides/normal-body-temperature 2.http : //news.ifeng.com/a/20160521/48815284_0.shtm
3. Aviv Bergman, Arturo Casadevall, 2010, Mammalian Endothermy Optimally Restricts Fungi and Metabolic Costs, mBio vol. 1 no 5 e00212-10 doi: 10.1128 / mBio.00212-109
4. RobertV. A. , CasadevallA. The 2009. Vertebrate endothermy restricts most fungi as potential pathogens. J. Infect. Dis. 200: 1623-1626.1 5.Wearden JH, Penton-Voak I S. Feeling the heat: body temperature and the rate of subjective time, revisited [J]. Quarterly Journal of Experimental Psychology B Comparative & amp; Physiological Psychology, 1995, 48 (2): 129-41.
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