Feedback is New Scientist A well-known figure who observes the latest news in science and technology with a critical eye. To share feedback about topics you believe may interest our readers, please contact us at feedback@newscientist.com.

Our Expiry Date

Unfortunately, we have some bad news. Humanity’s time is marked; experts predict our extinction by 2339, leaving us only a few centuries (as of now).

News Editor Jacob Aaron presented this startling information. A paper not yet peer-reviewed was shared on the social science preprint server SocArXiv. In their work, demographers David Swanson and Jeff Tayman discuss how the human population could decline from the current 8.1 billion to zero.

Their reasoning is straightforward: “Considering the decrease in birth rates from 2019 to 2024 and applying probabilistic forecasting methods, by 2139, the world’s population will fall between 1.55 billion and 1.81 billion… By 2339, humanity will be extinct,” they assert.

Swanson and Tayman highlight that this extinction timeline is “only 314 years away.” One might think the estimate could have been rounded to 300 to incorporate some necessary uncertainty in the predictions, but the confidence displayed is noteworthy.

This may seem evident, but we cannot base projections for the next three centuries on just five years of data — especially from 2019 to 2024, a period marked by significant global events that likely impacted birth rates.

They employed three different methodologies: the Cohort Component Method, the Hamilton-Perry Method, and even the notable Espenshade-Tiemann Method. Despite this, the prediction remains flawed. However, it’s likely our audience has already deduced this.

For a moment, we questioned if the paper was intended as satire, aiming to mislead unsuspecting science journalists into reckless reporting. However, this seems unlikely as Mr. Swanson shared it at a conference in September. Following his presentation, “a robust discussion unfolded.“Oh, I can’t believe I was heading straight for that wall.

This might hint at a precursor to a new belief system, positioning the apocalypse conveniently three centuries away to avoid embarrassment if it doesn’t come to pass.

Oh, No More

The feedback reveals that US President Donald Trump referred to climate change as “a scam, deeming renewable energy sources like wind power as “pathetic.”

This came in the wake of a government report published in July, generated by “independent researchers,” attempting to justify ceasing climate change mitigation efforts. Carbon Brief reviewed the report and identified over 100 misleading statements. Across the pond, the British Conservative Party has pledged to repeal climate change legislation upon regaining power.

The feedback notes that renewable energy has surpassed coal to become the leading source of electricity by mid-2025, which doesn’t seem particularly pathetic. Meanwhile, we’re reminded of that memorable scene from Monty Python and the Holy Grail, where monks beat their heads in a rhythmic fashion. We can only assume that these individuals read Swanson and Tayman’s paper and concluded that 2339 was too far off.

A Simple Thank You

One of the hallmarks of being an excellent researcher is to explore questions that others haven’t considered. Consequently, a study was published in the journal Socius in September: “‘This Task Would Have Been Impossible‘… A study examining the length of acknowledgments in sociology books.” Yes, that’s correct. This is an entire sociology paper dedicated to the acknowledgments section of sociology literature.

The first takeaway, as noted by the authors, is that they are not the first to pose this question. Back in 1972, Kenneth Henry Mackintosh published a study titled Approval Patterns in Sociology. When I searched for feedback online, I was disappointed to find that it was over 300 pages long and, even if the table of contents was accurate, it lacked an acknowledgments section.

What of the new research? The researchers evaluated 411 books written by 317 sociologists and examined the acknowledgments (excluding 7 percent for rudeness). A significant statistical trend revealed that female authors wrote longer acknowledgments than their male counterparts.

Similarly, books released by university presses contained longer acknowledgments compared to those from other publishers. It remains unclear whether this means they were thanking more individuals or simply elaborating more extensively.

Naturally, I was curious about the acknowledgments section of this very paper, so I scrolled down. We were pleased to see it consisted of 218 words and included a heartfelt mention of “steadfast love and support.”

Then, we discovered it wasn’t entirely original. Co-author Jeff Lockhart listed the paper on Bluesky, and another researcher quipped:I love that the paper itself has a lengthy acknowledgments section. In response, Lockhart remarked, “we felt it was necessary.”

I would like to acknowledge the cats who prevented me from stepping on my laptop keyboard while writing this article.

Have a story for feedback?

You can send your article to Feedback at feedback@newscientist.com. Please include your home address. You can find this week’s and past feedback on our website.