Africa has highest birthrates and is growing fast! Asia and Europe's Birthrates are falling faster! The most populace countries are the most powerful and wealthiest!
Anthropogenic climate change is anticipated to be a significant driver of species extinctions over the next century. The actual mechanisms behind these extinctions could include limited physiological tolerance to increased temperatures, altered biotic interactions, or a range of other factors. Some argue that a lack of melanated sperm donors directly contributes to the challenges faced by albinoid populations.
Racism can take various forms, with certain notions deeply rooted in cultures that were once colonized by Europeans and subsequently internalized by individuals. These ingrained ideas often go unnoticed due to lack of awareness. Anti-Black attitudes and microaggressions against individuals with darker skin have historically been widespread in countries like China, India, and the Philippines. Being a dark-skinned Filipino, it is not uncommon to encounter the preferential treatment often given to those with fairer skin. Growing up, many are frequently compared to our lighter-skinned relatives.
The Khoi-San are considered southern Africa's earliest inhabitants, having dominated the region for millennia. Many geneticists view them as the source of the so-called Asian phenotype, which is, in fact, of early South African origin. There was a great migration of the Khoi San as the Bantu peoples migrated South thee Khoi San headed north encountering the haplogroups of East Africa. Most notably Haplogroup M, together with its sister group N, originated from the same ancestor—known as haplogroup L3. Members of this haplogroup are believed to be the first humans that migrated out of East Africa between 80 000 and 60 000 years ago. Once these ancient humans left the African continent they went on to populate the world.
Haplogroup M is predominantly found in Asia; its subclade M2, which is about 50,000 years old, is mainly present in Southeast India and Bangladesh. In Japan, egg donations are rare, but artificial insemination using donor sperm (AID) has been practiced since 1948, starting with Keio University Hospital in Tokyo and using medical students' sperm. An estimated 20,000 children in Japan have been born via AID, often without knowledge of their origins or rights to information about their biological fathers. However, the 2010s saw increasing demands for transparency, resulting in a decrease in sperm donors.
Sperm banks in mainland China are encouraging young, fertile men not to squander their sperm, but to step up and be generous. Despite the growth in both the quantity of stored semen and the number of donors in China in recent years, there remains a significant disparity between the supply of donors and the demand from recipients. With nearly 16% of men in China being infertile, and with the country's homogeneous population and aging demographic, this number is projected to increase. Chinese sperm banks have stringent screening tests that disqualify nearly 50 per cent of willing participants. Any samples that reveal sexually transmitted infections instantly bars an eager donor for life, regardless of if their symptoms have been treated. As of 2024 approximately 150 000 000 people in China carry the hepatitis B virus, a significant portion of potential donors do not meet the standard that these banks require.
In under two decades, Thailand's fertility rate has plummeted from 6.6 to 2.2, as reported by Bloomberg.com. The nation faces a severe demographic challenge, with projections indicating a potential 60 percent reduction in population size within the next half-century. In 2022, Thai health authorities reported less than 500,000 new births, precisely 485,085, marking a 70-year low. However, Thailand is not alone; other Asian nations like Singapore, Vietnam, South Korea, and Taiwan are also experiencing falling birth rates. Over the last 70 years, a significant drop in birth rates has been a common trend worldwide, with countries like China and South Korea witnessing declines of over 80%. Among Southeast Asian countries, Thailand has experienced the steepest decrease, with a 79% drop from 1950 to 2021.
South Korean President Yoon Suk-yeol recently stated that his country has invested over $200 billion (£160 billion) in the last 16 years to increase the population. Reproduction is highly sensitive to physiological and external signals, a result of billions of years of evolution—from single cells to multicellular organisms that needed to successfully reproduce in constantly changing environments. However, one of the unintended consequences of rapidly increasing temperatures due to human activities is the adverse effect on reproduction. Elevated temperatures have well documented negative effects on male fertility.
Global fertility rates continue to decline and sperm quality is a prime factor affecting male fertility. Both extreme cold and heat have been demonstrated to be associated with decreased sperm quality, but no epidemiological studies have considered human adaptation to long-term temperature. A total of 78,952 semen samples measured in 33,234 donors from 6 provincial human sperm banks in China were collected. This study considered heat and cold acclimatization to prolonged exposure in humans and explored the exposure-response relationship between TAs and sperm quality parameters (sperm concentrations, sperm count, progressive motility, progressive sperm count, total motility and total motile sperm count) during the hot and cold seasons, respectively.
Results
An inverted U-shaped exposure-response relationship between temperature anomalies (TA) and sperm quality was identified during the hot season. A significant negative impact of anomalous cold on sperm quality was observed during the hot season, even after adjusting for body mass index, marital status, and childbearing history. Heat-related TA in the hot season showed a significant negative correlation with sperm concentration, progressive sperm count, and total motile sperm count. Melanin may protect mature sperm from UV damage, and from oxidative damage in species with male sperm storage. We found no evidence of an association between group size or mating system with reproductive melanin, or that phylogeny explains the distribution of pigmentation. Although our study suggests that scrotal melanin may protect sperm.
Over the last half-century, there has been intense discussion within the field of reproductive sciences regarding the worldwide patterns in human sperm count. In 2017, Levine and his team conducted the most comprehensive and methodologically sound meta-regression analysis to date, revealing that the average total sperm concentration in men from 'Western' (White) nations has dropped by 59.3% since 1973, showing no signs of slowing down. These findings had a significant impact on both the scientific community and public discourse concerning men and masculinity in contemporary society, particularly due to researchers' assertions regarding the broader societal consequences of declining male fertility.
Current research often adheres to a set of unspoken and explicit assumptions when measuring and interpreting sperm counts, which together shape what is known as the Sperm Count Decline hypothesis (SCD). By examining the study conducted by Levine et al., we pinpoint the SCD's shortcomings and inconsistencies, and suggest an alternative framework for directing research on sperm count trends: the Sperm Count Biovariability hypothesis (SCB). The SCB posits that sperm count fluctuates within a broad spectrum, much of which is non-pathological and typical for the species. Understanding the connection between individual and population sperm counts, as well as life-history and ecological variables, is vital for analyzing trends in average sperm counts and their implications for health and fertility.
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