Scientists role play as Neanderthals to discover a dietary secret

It was the dead of night when a team of Spanish scientists snuck into a pitch-black cave along Spain’s Iberian peninsula.

Adorned with headlamps, this team of researchers moved stealthily beneath a chattering of choughs — a jet black bird with flame-red legs and beak. In a burst of activity, the choughs were dazzled and confused by the sudden light, and the chase to “capture” and tag the raven-like birds began.

But while the chough’s nesting habits were of interest to the researchers, it was really predators from their past — whose hunting style they were mimicking — who interested the team most: the Neanderthals.

“In our study, we captured choughs in caves at night and assumed that Neanderthals could have done the same,” Juan José Negro, a co-author on the new work and evolutionary ecologist at Estación Biológica de Doñana in Spain, tells Inverse.

“We just walked in the caves with headlamps and nothing else than our bare hands — and some ability to climb here and there,” Negro continues. “Just substitute our headlamps with fire torches, and the same job may be done by a group of hunting Neanderthals ... it’s a matter of entering the cave with a headlamp, and you just grab as many choughs as you can with your bare hands — like collecting apples from a tree.”

The research team has been studying chough for many years, says Negro, but it was only recently they realized that their night-time capture-and-release might have Neanderthal origins.

However, while this experiment might look like role-play from the outside, Negro and co-author Antonio Sánchez Marco say it’s actually closer to what’s called an “actualistic experiment.”

“Actualistic experiments are the ones performed today to infer and interpret events of the distant past,” Negro says.

On the other hand, roleplay has a “much broader meaning,” Sánchez Marco tells Inverse, and can be considered less rigorous.

What’s new — Like the Voynich Manuscript or the missing pieces of Amelia Earhart’s plane, the mystery of what life was really like for Neanderthals is fascinating precisely because it’s challenging to uncover.

Fossilized evidence helped scientists learn about Neanderthal’s bodies — that they were likely shorter and squatter than Homo sapiens — and pieces of ancient food stuck in Neanderthal teeth or fecal samples has led scientists to speculate on their possible diets. However, understanding how Neanderthals interacted with each other is more complicated.

That’s a problem that this study, published last week in the journal Frontiers in Ecology and Evolution, can help answer.

“Neanderthals would easily grab helpless choughs roosting in crevices and cave ledges.”

The fossil record shows that choughs and Neanderthals have a lot of overlap with each other. Given the modern chough’s skillful evasion of daytime predators, scientists hadn’t yet understood whether Neanderthal’s could’ve possibly hunted these animals. Using an actualistic approach, the research team investigated how Neanderthals might’ve hunted choughs at night in the caves they both called home.

“Neanderthals, of course, did not have electric appliances, but they could resort to fire torches,” says Negro. “Plus, Neanderthals had larger eyes that we have and were thus well endowed for moving around in dim light.”

Why it matters — Understanding how Neanderthal’s might’ve hunted these crow-sized birds not only satisfies a research itch for historical LARPing, but can also help them better understand the nutrient profile of Neanderthal’s diets, as well as how they might’ve worked together during nocturnal hunts.

“Controlling fire, Neanderthals had access to new dietary items, such as choughs, which were hard or impossible to get during daytime,” says Negro. “At night most birds become extremely vulnerable and need to hide and rest. With some intelligence and the use of some light [like] fire, Neanderthals would easily grab helpless choughs roosting in crevices and cave ledges.”

How they did it — To get into their roles as modern-day Neanderthals, the researchers first had to round up some possible cave candidates for their chough search. Through a literature review, they pinpointed many possible chough caves along the Iberian peninsula.

During 296 trials at 70 different roosting spots, the researchers report that they were able to capture, tag, and release 5,525 choughs using Neanderthal-age techniques like dazzling, corralling, and grabbing birds from the air.

In some instances, the researchers even freely scaled rock faces in the caves, which they write in their paper that Neanderthal’s would’ve been better equipped to do than Homo sapiens with their shorter stature.

Based on the caloric content of the choughs, the researchers estimate that each Neanderthal would’ve eaten about two to three birds to feel satisfied. For a Neanderthal group of 10-20 adults and children, the feast might’ve required 40-60 choughs. Which the team write “could be entirely possible” according to their experiments.

More than just a source of calories for the hungry Neanderthals, these choughs would’ve also been an important source of micronutrients such as carotenoids. These nutrients would’ve played a role in keeping Neanderthal’s vision and immune systems running smoothly.

What’s next — While this research can’t conclusively confirm whether or not Neanderthal’s hunted choughs in this way, the findings show that this scenario would have been easily achievable by a Neanderthal hunting party.

In the future, the researchers say they plan to continue diving deeper into this question — though new research may not include role play.

“Paleontologists started to look at bird fossils under the microscope quite recently — in the 21st century — and readily found cut and tooth marks, demonstrating processing and consumption by humans,” says Negro. “The emerging field of ancient DNA will surely bring about exciting discoveries [and] new techniques underway may reveal unsuspected relationships!”

Abstract: Evidence is accumulating on the regular and systematic Neanderthal exploitation of birds. However, the motivations, mechanisms, and circumstances underlying this behavior remains little explored despite their potential implications on Neanderthal ecology and capabilities. Fossil remains of choughs (Pyrrhocorax, Corvidae) are among the most abundant in cave sites with Mousterian technology. We reviewed the evidence showing that Neanderthals processed choughs for food, and confirmed that it occurred frequently over a widespread spatial and temporal scale. This lead us to propose the hypothesis that the cave-like refuge is the keystone resource connecting Neanderthals and choughs captured at night in rocky shelters eventually used by both species. By adopting an actualistic approach, we documented the patterns of refuge use and population dynamics of communally roosting choughs, the strategies and technology currently used to capture them, and their behavioral response against experimental human predators at night. Actualistic experiments showed that large numbers of choughs can be captured without highly sophisticated tools at night regularly and periodically, due to their occupation year-round during long-term periods of the same nocturnal shelters, the constant turnover of individuals, and their high site tenacity at these roost-sites even after recurrent disturbance and predation. Captures even with bare hands are further facilitated because choughs tend to flee confused into the cavity in darkness when dazzled and cornered by human (experimental) predators. Given the extreme difficulty of daylight chough capturing in open country, nocturnal hunting with the help of fire in the roosting caves and consumption in situ are proposed as the most plausible explanations for the strong association of choughs and Neanderthals in fossil assemblages. Night hunting of birds has implications for the social, anatomical, technological, and cognitive capacities of Neanderthals.