The elusive and ancient Wonderwerk Cave has attracted scientific attention for decades for its early human use, but a new study found even older traces of fire in this location.

As the lead author stated from the National Museum of Natural Sciences in Madrid, “this is a study of great interest to global prehistory, as it addresses one of the most significant topics for humanity: fire.”

In a new study published in PLOS, researchers analyzed 161 fossils with a new rapid and non-destructive protocol, based on stimulating the bone remains with an external energy source, called luminescence.

Science Media Centre continues that study authors applied this new methodology to the bones of small animals that were part of pellets, or “the undigested and regurgitated remains of prey of nocturnal birds of prey.”

These bones mixed in with these pellets, 1.8 million years old, exhibited signs of having been burned, so the team behind the study is proposing that these pellets were used to make fire inside the Wonderwerk Café, at deeper layers (meaning time) than they thought.

The oldest burnt bones ever

The fossils came from small mammals that researchers recovered from two Early Pleistocene layers, or 30 meters deep. Because this material was found at such profound layers, researchers had to hypothesize that accidental burning would have been impossible.

These animals purportedly wandered into the cave through “barn owl activity,” which refers to owl pellets, which, over thousands of years, piled up. They showed signs of burning.

The novel analytical technique detected any changes in the bones, caused by heat, and cross-examined the results with modern bones as well as Bronze Age material from another site, and they were able to determine that these fossil bones were burned, according to Archaeology News.

Not only were they burnt, but the pattern indicated that the act of burning occurred over time, at specific parts of the cave, so there was some localized event happening again and again. Furthermore, the material in question sat beside tools and other animal remains, with Homo erectus being the early humans working with fire.

But when did humans learn to control fire? Ah, the question

This study touches a pivotal moment in human history, if not the dawn of civilization, technology. The use of fire, as per Heritage Daily, sparked much more than the flame, but advanced human development with new fuel. At this time in history, researchers have failed to find any evidence that humans could make fire themselves.

Traditionally, the oldest fires are believed to be the result of exploiting natural fires. But this new proposal adds a new behavior into the mix, by suggesting this wasn’t a passive act, but deliberate. They didn’t appear to ignite these fires in the cave, but rather they brought them into the cave from outside, on torches. Because, how else would they have transported the flames?

And, for the moment, though this study presents even more thrilling evidence that perhaps humans, at this time, were able to control fire? “Before this article, no fires involving human activity of such antiquity had been recognized,” as per Science Media Center.

However, Heritage Daily concludes, when humans first learned to control fires is still one of the “most fiercely argued questions…” Until then, it seems we were working with fire even earlier in time than we ever even knew.

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Astronomers believe they may have found evidence that one star in a faraway binary system may have eaten its own planets in the past. If true, this may well violate the generally accepted rules governing the formation of binary star systems.

The star system in question, HD 81809, lies in the constellation Hydra and is roughly 90 to 101 light-years from Earth. It consists of one main primary star, HD 81809A, which is now in its twilight years, having spent its hydrogen fuel.

The second, HD 81809B, is still a main-sequence star, but also has a noticeably different composition from its larger twin. Under “normal” circumstances, at least as far as we believe, binary stars typically form together from the same gas cloud. They also tend to form at roughly the same time.

According to researchers from the Technical University of Denmark, studying it, it has significantly more lithium, and the iron content appears different between them, too. In fact, the difference is about 3.7 times (0.57 dex in technical speak).

A case of hungry, hungry stars

While some variance would be expected, the research team believes that the differences are too large to be ignored. Something else has happened in the past, but what?

Well, the only logical answer seems to be that the “metal-rich” star must have swallowed planets or other planetary material sometime in the past. Likely candidates would be rocky planets (like our own Earth), which tend to be rich in iron, silicon, magnesium, etc.

If a star consumes them, its outer layers become chemically enriched, which can be detected from afar. This hypothesis is also supported by other evidence, such as what appears to be a debris disk around the star.

What likely happened, the team explains, is that the planet spiraled inwards towards the star, became orbitally unstable, and was eventually absorbed. All well and good, but the high levels of lithium may point to a very recent event.

Lithium usually doesn’t survive very long inside stars and may point to very fresh planetary materials being introduced. However, computer modeling suggests that the star would have needed to eat huge amounts of planetary material, roughly between 25 and 75 Earth-like bodies.

Planet-munching star caught red-handed?

But if this were the case, the level of lithium should be much higher than observed. “The models predict that such a metal-rich accretion would over-enrich lithium at the surface; matching the observed lithium instead requires accreting less than 6 M_⊕,” the team writes in the paper.

“This tension highlights the need for precise knowledge of the accreted material’s chemical composition,” they added.

While they cannot be entirely sure, the team believes that engulfment was likely recent and may have involved “unusual” composition planets. Either that, or only certain kinds of planets or materials were actually absorbed by the star.

Likely, we may never know, but whatever is going on with HD 81809B certainly deserves further research.

You can view the study for yourself in the journal arXiv.

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