Scientists Share 49 Things They Suspect Are True But Are Not Yet Proven As Fact

Last year was a busy year for scientists. Well, every year is, but last year was no different. The brainy men and women in their respective fields were researching theories left, right, and center, and they managed to make some major breakthroughs.

According to the Smithsonian Magazine, 2025 was the year in which scientists drilled some of the oldest ice ever recovered, researched a cancer blood test, and identified the pathogen behind a devastating decline of sea stars.

"Astronomers surpassed 6,000 confirmed exoplanets, and a new observatory unveiled its first space photos," it adds. "Rock fragments offered tantalizing evidence that humans set the first deliberate fires roughly 350,000 years earlier than thought."

Ordinary people also contributed to science by sharing rare videos that captured a meteorite striking the ground, as well as an earthquake fault in motion.

One of the big scientific moments of 2025 happened right at the beginning of the year, when surgeons in America performed an organ transplant that was anything but ordinary. Instead of using a human kidney, the doctors successfully transplanted a gene-edited pig kidney into a man called Tim Andrews.

While it was the fourth transplant of its kind in the States, it was a breakthrough in terms of how long the organ kept working. Andrews lived with the pig organ for a record-breaking 271 days before it failed and was removed in October, the Smithsonian reveals.

"Andrews got a reprieve from dialysis for much of this year—and, as a living symbol of hope for other patients in need of kidney transplants, he threw the first pitch at a Boston Red Sox game," adds the publication.

That same year, scientists over in China reported a successful transplant of a portion of a pig liver, which they removed after 38 days. This is good news for people waiting on a lifesaving organ transplant in a world where supply does not meet demand.

Pigs have metabolisms, immune systems, and organ sizes that resemble those of human beings, and scientists now believe they may hold the key to saving thousands of lives.

Also in 2025, a team of of astronomers identified what they called the “strongest evidence yet” of life on another planet. They found two chemical compounds on an exoplanet far, far away, that they say are only produced by living things.

"The discovery, reported in April in Astrophysical Journal Letters, came from James Webb Space Telescope data about the world K2-18b," reports the Smithsonian. "The exoplanet, orbiting a star 124 light-years away, had already seemed like a candidate for hosting life."

It's important to note that the scientists did not find actual life-forms on the exoplanet—only the signatures of the compounds, known as dimethyl sulfide (DMS) and dimethyl disulfide (DMDS). They're both sulfur-based gases found on Earth and produced by living things like algae.

While it is a big deal, the discovery is not a definite sign of life outside of Earth. That's because some experts believe that DMS and DMDS can be made in a way that doesn’t require any living organisms. It's likely going to take more time and research to find definitive proof of life in space.

While some discoveries and breakthroughs in 2025 were intriguing, others were downright bizarre, like the creepy thing now known as the 'Bone Collector."

It's a species of caterpillar that was spotted wearing the leftover body parts of the prey it had devoured as camouflage. Straight out of a Steven King novel, this insect is a rare exception in the insect world, reports BBC Science Focus: "just 0.1 per cent of moth and butterfly species are carnivorous."