Researchers successfully cloned a single mouse and then repeatedly cloned its descendants for 58 generations over two decades, producing more than 1,200 animals from one original donor.
Yet the experiment ultimately ended in failure when the entire lineage collapsed due to accumulating genetic damage. This visual powerfully captures the central message of the study — that while cloning can produce healthy-looking individuals for many generations, it cannot sustain a viable lineage indefinitely in mammals.
The experiment, led by Teruhiko Wakayama and Sayaka Wakayama at the University of Yamanashi in Japan, began in 2005 using somatic cell nuclear transfer (the same technique that created Dolly the sheep). Early generations of clones appeared normal, lived typical lifespans, and even showed slightly improved cloning success rates at first. However, subtle problems emerged after roughly the 25th–27th generation.
Cloning efficiency declined sharply, and by the 57th generation, the success rate had fallen to just 0.6%. All mice in the 58th generation died within a day of birth, despite showing no obvious physical abnormalities.
Whole-genome sequencing revealed the underlying cause: harmful mutations accumulated progressively with each round of cloning. Without the genetic shuffling provided by sexual reproduction, deleterious changes — including point mutations, chromosomal abnormalities, and loss of the X chromosome in some cases — could not be purged. By the later generations, the mutation load had become overwhelming, leading to what researchers described as a form of “mutational meltdown.”
This long-term study provides the clearest evidence yet that mammals cannot maintain a species through cloning alone. Sexual reproduction remains essential for resetting genetic errors and maintaining long-term viability. The findings carry important implications for cloning technology, regenerative medicine, and our understanding of genome stability.
[Wakayama, S., Ito, D., Inoue, R., Ooga, M., Toshishige, M., Satoh, Y., Shiura, H., Kohda, T., Uchimura, A., & Wakayama, T. (2026). Limitations of serial cloning in mammals. Nature Communications. DOI: 10.1038/s41467-026-69765-7]
"Billionaires don't need more money. Somebody with $100 million doesn't need more money. A Fortune 500 CEO doesn't need more money. They want relationships. It's not about what you get, but what you have to give."
Elon just created 4,400 millionaires in a single day.
400 of them are now worth over $100 million.
These aren't VCs. They're SpaceX employees, and the list includes welders, technicians, and cafeteria staff, because for two decades the company paid every level of the workforce in stock instead of higher salaries.
Juan Hernandez immigrated from Mexico and took a $28 an hour contractor welding job in 2015. He says he didn't even know what SpaceX was. The company gave him a $10,000 equity grant and let him buy more shares through payroll deductions. That stake is now worth $880,000.
Trevor Hise's parents wanted him to take a stable job at General Electric. He picked SpaceX instead, stayed 12 years, and accumulated over 100,000 shares. At the $135 listing price that's $13.5 million. He's 37 and semiretired. His words: "The magnitude of this has been ridiculous."
The most telling detail came before the listing. Over 100 employees quietly banded together and negotiated a group wealth management deal covering up to $5 billion, because none of them had ever needed a wealth manager before.
Software IPOs have minted millionaires for 30 years. This is the first one where the money went to the factory floor.
NAILED IT: Jeff Bezos: “A nurse in Queens who makes $75K a year pays more than $12K a year in taxes. Does that really make sense?”
“So people talk about making the tax system more progressive. How about we start by having the nurse in Queens NOT pay taxes? At all!”
“Why is a nurse in Queens who makes $75K a year paying more than $1K a month in taxes?”
“That’s $1K a month that could help with rent or groceries or anything.”
“And by the way, do you know what that all adds up to? The bottom half of income earners in this country pay only 3% of the taxes. It’s only 3%.”
“We can find 3%. So we don’t have... it’s a small amount of money for the government. You know that. And the more I thought about it, to me, it’s kind of absurd that we’re doing this.”
“We shouldn’t be asking this nurse in Queens to send money to Washington — they should be sending her an apology. It really makes no sense.”
Exactly!