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The Global Population Climate Change To Blame?

The world is ill-prepared for the global crash in children being born which is set to have a "jaw-dropping" impact on societies, say researchers according to a recent BBC article.

Falling fertility rates mean nearly every country with the exception of those in Africa will have noticeably smaller populations by the middle of the century. Twenty three nations - including Spain and Japan - are expected to see their populations halve by 2060. Countries will also age dramatically, with as many people turning 80 as there are being born. The fertility rate - the average number of children a woman gives birth to - is falling rapidly. When the number falls below approximately 2.1, then the size of the population starts to fall. Presently this has occurred in ALL European nations, Japan, Portugal, Greece and Taiwan have extremely low birth rates but South Korea has the lowest fertility rate globally at 0.9 children per woman, closely followed by Puerto Rico at 1.0 and a trio of Malta, Singapore, and the Chinese Special Administrative Region Hong Kong all at 1.1 children per woman. In 1950, women were having an average of 4.7 children in their lifetime.

Researchers at the University of Washington's Institute for Health Metrics and Evaluation showed the global fertility rate for non African nations nearly halved to 2.4 in 2017 - and their study, published in the Lancet, projects it will fall below 1.7 by 2060.As a result, the researchers expect the number of people on the planet to peak at 9.7 billion around 2064, before falling down to 8.8 billion before the end of the century. "That's a pretty big thing; most of the world is transitioning into natural population decline," researcher Prof Christopher Murray told the BBC."I think it's incredibly hard to think this through and recognize how big a thing this is; it's extraordinary, we'll have to reorganize societies." The big question is Why are fertility rates falling? It has nothing to do with sperm counts or the usual things that come to mind when discussing fertility.

At first it was thought to be driven by more women in education and work, as well as greater access to contraception, leading to women choosing to have fewer children. Although this concept has some credence in the west it does not account for the decline in nations that do not have a high level of literacy for women but actually stems from a debunked book written in the 1800s that argued education killed women! In his 1876 book Sex in Education: Or, a Fair Chance for Girls, Harvard Medical School physician Edward H. Clarke based his assertion on the theory that the sum of energy in a body is constant. So, a woman who spent her time on the “excessive” studying required in college would transfer energy from her reproductive organs to her brain.

Clarke described what he saw as “numerous pale, weak, neuralgic, dyspeptic … girls and women that are living illustrations of this monograph.” In vivid words, he described the “thousand ills” of American women, all attributed to the “educational methods of our schools and colleges.” Although today we can easily dismiss and even laugh at Clarke’s theories, his assertions left an indelible mark on the minds of ACA leaders for many years. It was still a vivid memory at their 25-year anniversary meeting held in Boston, Massachusetts, in 1908. In the welcoming address, Florence Cushing reminisced about the days “a little more than a quarter century ago when, almost within a stone’s throw of this building, one of the noted physicians of Boston wrote, ‘It is the first observation of a European landing on our shores that the women of the country are a feeble race.’” She continued with a greeting to Clarke: “Some of the remnants of this ‘feeble race’ are here to give you a welcome tonight.”(AAUW, Suzanne Gould 2013)

Japan's population is projected to fall from a peak of 128 million in 2017 to less than 50 million by the end of the century. Japan by 2100, will see 35% of Japanese aged over 70, according to the United Nations. Italy is expected to see an equally dramatic population crash from 61 million to 25 million over the same timeframe. Nearly a quarter of Italy's population is aged 65 or older, at 23.2 percent, and that is expected to grow to 35 percent by 2050! These are two of 23 countries - which also include Spain, Portugal, Thailand and South Korea - expected to see their population more than halve "That is jaw-dropping," says Prof Christopher Murray. China, currently the most populous nation in the world, is expected to peak at 1.4 billion in four years' time before nearly halving to 700 million by 2100. Nigeria will take its place as the most populous country.

India's fertility is declining and at present the country is experiencing significant demographic transition. Currently the second most populous country the CIA World Factbook estimates the population is 72% Indo-Aryan, 25% Dravidian, and 3% Mongoloid and other. The melanated Dravidian population has seen no significant declines in population. There are around 250 million native speakers of Dravidian languages. Dravidian speakers from the majority of the population of South India and are natively found in India, Pakistan, Afghanistan, Bangladesh, the Maldives, Nepal, Bhutan and Sri Lanka. Northern India is primarily Indo-Aryan and has seen a significant drop in fertility and is currently below the replacement level of fertility of 2.1 children per woman. The UK is predicted to peak at 75 million in 2063, and fall to 71 million by 2100. Whites will be an ethnic minority in Britain by the end of the century. Analysis of official figures indicate that, at current fertility rates and levels of immigration, there will be more immigrants than indigenous Brits by 2100. It would be the first time in history that a major indigenous population has voluntarily become a minority, rather than through war, famine or disease.


However, this will be a truly global issue, with 183 out of 195 countries having a fertility rate below the replacement level. You might think this is great for the environment. A smaller population would reduce carbon emissions as well as deforestation for farmland. "That would be true except for the inverted age structure (more old people than young people) and all the uniformly negative consequences of an inverted age structure," says Prof Murray. With the exception of Africa, the Caribbean and parts of India and South America (most notably Brazil, Venezuela, Cuba and Honduras )The world faces a shift from young to old.

Countries, including the UK, have used migration to boost their population and compensate for falling fertility rates, however, this stops being the answer when racial demographics come into play. Some countries have tried policies such as enhanced maternity and paternity leave, free childcare, financial incentives and extra employment rights, but there is no clear answer.

The population of sub-Saharan Africa is expected to triple in size to more than three billion people by 2100. And the study says Nigeria will become the world's second biggest country, with a population of 791 million. Prof Murray says: "We will have many more people of African descent in many more countries as we go through this. "Global recognition of the challenges around racism are going to be all the more critical if there are large numbers of people of African descent in many countries in fact making up the bulk of those countries."

Some experts believe Climate Change is the cause of the global demographic change in the world. Fertility is reduced because heat stress can damage both the oocyte and early embryo (Hansen, 2013). The oocyte can be compromised by heat stress as early as 105 days before ovulation (Torres-Júnior et al., 2008) and as late as the peri-ovulatory period (Putney et al., 1989b).UCLA researchers showed that the number of births in the U.S. fell in the nine months after an extreme heat event while a study of 18,000 couples in China last year showed that climate change, and particulate pollution in particular, was associated with a 20% increased likelihood of infertility.

The effects from rising temperatures, a symptom of climate change, have become a significant concern.

This study finds that one additional day with a maximum temperature of 30–32 °C (86–89.6 °F), relative to a day with a temperature of 28–30 °C (82.4–86 °F), decreases the birth rate 9 months later by 0.24%, or 92 babies per month in South Korea. This result is robust to various specifications and samples. This study also found that the impact of the temperature bin did not vary according to the mother’s characteristics, including education and age. That is, high temperature has no differential effect on mothers of different backgrounds. Finally, we found no significant temperature effect on birth outcomes, but we cannot rule out that children born 9 months after summer heat are a selected (healthy) group. “Heatwaves reduce male fertility and sperm competitiveness, and successive heat waves almost sterilize males with low amounts of melanin, ”A recent report in the journal Demography, a study found that high temperatures have a significant negative effect on fertility and birth rates, and the research projects that as climate change drives temperatures up and increases the number and severity of heat waves, getting pregnant may become harder than ever.

"If you look nine months after a heat wave in August, the following May you see significantly fewer births," Researcher Environmental Economist Alan Barreca said.

It's not that people have less sex in hot weather. ( research by Barreca indicates people actually have more sex when temperatures rise.) Rather, the pattern is likely due to heat's effect on male fertility: Studies show that sperm production falls in hot weather, he said. The researcher also found that from 1969 to 1988, an average of 25,000 births per year came before expected because of heat exposure. It is estimated that by the end of the century, the figure will rise to 42,000 births per year, the study stated children born early have a higher mortality rate.

The reduction in fertility occurred across all regions of the U.S., with hot states like Arizona seeing the same trends as cooler ones. Barreca said this may be because those who live in warmer climates are better adapted to the heat or avoid it by staying inside air conditioned buildings. In fact, the effect was slightly more pronounced in northern states, where people are less prepared for heat waves. This can be projected for European countries as well who have very little heat infrastructure speeding up a demographic decline!

Increased UV radiation can have an effect on human fertility over generations, a new study has warned. Researchers from the Norwegian University of Science and Technology (NTNU) studied information from more than 9,000 people listed in the church records from 1750 to 1900 in Norway. Gine Roll Skjaervo found that children born in years with lots of solar activity had a higher probability of dying compared to children who were born in years with less solar activity. On average, the lifespan of children born in years that had a great deal of solar activity was 5.2 - 10 years shorter than other children. The largest difference was in the probability of dying during the first two years of life. Children who were born in years with lots of sunshine and who survived were also more likely to have fewer children, who in turn gave birth to fewer children than others.This finding shows that increased UV radiation during years of high solar activity had an effect across generations.

Skjaervo used information on the number of sunspots as an indication of the amount of UV radiation in a given year. The number of sunspots reaches a maximum every 11 years on average, which results in more UV radiation on Earth during years with high sunspot and solar activity. UV radiation can have positive effects on human vitamin D levels, which is most beneficial for darker skinned people who don’t get enough sunlight, but for fairer skinned populations it can result in a reduction of vitamin B9 (folate).In a 1978 paper by two American medical researchers, Anthropologist Nina Jablonski found evidence linking exposure to strong sunlight with low levels of folate, an essential B vitamin, in the blood. Other research tied folate deficiency in pregnant women to various birth defects. In men, she learned, folate is vital for sperm production.

These and other observations gradually led her and her husband and collaborator George Chaplin, Senior Research Associate in Penn State’s Department of Anthropology, toward a new hypothesis: that humans evolved the ability to produce melanin, the dark-brown pigment that acts as a natural sunscreen, as a way of safeguarding the body’s store of folate. It is now widely known that low folate levels during pregnancy are linked to infertility and higher child mortality. The study showed that Norwegian families from the lowest socio-economic groups were most affected by UV radiation because they worked outdoors more frequently. Studies also have shown that increasing temperatures can hinder sperm production and that heat waves consistently impair male reproductive health.

Other environmental issues that may affect male fertility include poor air quality and endocrine disruptors found in common everyday items like plastics. Researchers have recently confirmed an alarming trend: western male sperm count has dropped by 50-60% over the last 40 years with no signs of leveling-off. This temperature dependence has been clearly demonstrated by several experimental studies showing that artificial increases in scrotum or testicle temperature in fertile men reduce both sperm output and quality. The sperm of the male and the egg of the woman both are layered with melanin. So when the sperm penetrates the egg, there is a melanin explosion. This helps to formulate the fetus. Some researchers hypothesize that scrotal melanin may protect mature sperm from UV damage, and from oxidative damage in species with male sperm which is why we don’t find a drastic drop of sperm count in African men.


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