Coffee Break: Ancient Travelers and Artists, an Enigmatic Devonian Giant, and a Thinking Cow

After one full year the grim news on the science front – all fronts really – this Coffee Break is devoted to why science is interesting and fun.  And useful, even if its use value cannot be predicted before the fact.

Part the First: Ancient Travelers.  Or, social networks (not this kind) have always been essential to human flourishing.  They were wide, geographically and genetically, more than a thousand generations ago.  This news article in Science tells the tale: Ice age Europeans imported tools from distant lands, perhaps as souvenirs:

To survive Europe’s bitterly cold ice age some 25,000 years ago, people did what people do best: They networked. In a paper published today in Science Advances (open access) archaeologists report finding stone tools in central Spain that came from almost 800 kilometers away, the farthest confirmed distance a stone tool has been found from its source in this time period, known as the European Paleolithic.

To wind up there, the artifacts must have been carried or exchanged by people living during one of the coldest periods in the past 50,000 years. “That’s way beyond what we expect for hunter-gatherers,” says Solange Rigaud, an archaeologist at CNRS, the French national research agency, at the University of Bordeaux who was not involved with the research.

Archaeologists found the stone tools while excavating a riverside rock shelter called Peña Capón, about 100 kilometers north of Madrid. Between about 26,000 and 22,000 years ago, people living there fished for salmon and used stone and bone tools to hunt and butcher deer, horses, and rabbits.

Located on the far side of a reservoir created by damming the Sorbe River, the rock shelter is tricky to access. Archaeologists had to cross the reservoir on a boat each morning and could only work from October to December, when the reservoir’s water level dropped enough to expose the site. “Working conditions were often uncomfortable, cold, and wet,” says University of Alcalá archaeologist Manuel Alcaraz-Castaño, who led the excavations and was a co-author of the new paper.

As the original article states, “Social networking is an essential feature of hunter-gatherer societies.  It fosters the circulation of goods and information and enables kinship ties across different scales, including long-distance contacts.”  And they were a long distance, across the Pyrenees, 600 – 700 kilometers away.

I can hear the skeptics now, “Why should we care about that?”  I would answer “because human prehistory is just as important as human history”:

The data suggest that the large social network connecting Southwest France to Central Iberia, sustained for at least ∼1400 years, was not only intended at mitigating subsistence risk but also maintained social and cultural cohesion among different local and regional groups by promoting the circulation of ideas and symbols.

We are still all in this together and this should not be forgotten, especially in the current political and geophysical climates, with the latter impinging on the former more and more every day.

Part the Second: Very Ancient Art from World Travelers.  From Scientific American, Oldest cave art ever found discovered in Indonesia, dating back at least 67,800 years, 15,000 older than the next-oldest cave art on the same island of Sulawesi.  Our deep-time ancestors were social beings with social networks.  They were also artists, and one wonders what they were thinking when they used pigment to leave these true artifacts on the walls and ceilings of caves in Indonesia.

Beating the previous record for the oldest known cave artwork by at least 15,000 years, a hand stencil in an Indonesian cave might shed light on when early humans migrated to Australia

In an Indonesian cave system known for its prehistoric art, the oldest cave art yet found was hiding in plain sight. In a cave full of paintings that were well studied over the years, a faint hand stencil on the ceiling had been overlooked. A new chemical analysis of the stencil reveals that it dates back at least 67,800 years, an astonishing 15,000 years older than the next-oldest cave art found on the same island, Sulawesi. A nearby stencil dated to about 60,900 years ago.

“We knew that they were probably going to be old…, but we didn’t know how old,” says study co-author Maxime Aubert of Griffith University in Australia.

The record-breaking finding, published today in Nature, might provide valuable information about the first humans to reach Australia.

The age of this previously undiscovered artwork is “really astonishing,” says Franco Viviani, a physical anthropologist who was not involved in the new study. Viviani adds that shifting back the time line of cave art gives us new insights into what ancient societies were capable of. “They confirm what is known today: that art is positively correlated to critical thinking and creative problem-solving skills,” he says.

Scientists were already aware of the ability of early humans and other ancient hominins to create art, such as shell jewelry made by humans at least 70,000 years ago and 57,000-year-old engraved bones attributed to Neandertals. Still, the cave art in the new study is among the oldest evidence yet of paintings by modern humans, and its distinctive style gives a view into the minds of the people who created it.

Yes, these paintings do give us an inkling of what was on and in the minds of these ancestors, but only that.  Still, our forebears were remarkable human beings.  We should honor them better than we do.  The underlying paper is open access, technical but worth skimming: Rock art from at least 67,800 years ago in Sulawesi.  Having done research in a few fairly remote stations, I am envious of the archaeologists responsible for Parts the First and Second here.  None of them is getting rich, which has become the one and only goal suffusing the higher reaches of the Neoliberal Dispensation, but all of them are enjoying their work.

Part the Third: Biology Is Always Interesting.  Ever since my sixth-grade teacher told the class we would not be discussing evolution, the subject has fascinated me.  Ten years later I took a course in evolutionary biology from a pioneer in molecular evolution.  I was hooked and my recent “real” research has been on the co-evolution of proteins in the multicomponent assemblies that are essential for animal multicellularity.  With a modicum of good fortune, I have one last good paper in me.

There are still a few fossil organisms that don’t really fit, however.  One of my favorites is the placozoan Trichoplax adhaerens.  Is it representative of the first multicellular animal?  Maybe.  Arguments continue but it is a fascinating creature, sometimes found on the glass of an aquarium hosting sea creatures in seawater from the wild.  Another fossil that doesn’t fit is Prototaxites, which was a tree-like organism, without branches, before there were trees.  From Scientific American, Mystery tower fossils may come from a newly discovered kind of life:

Before trees came along some 400 million years ago, our planet’s landscape was dominated by enigmatic, spire-shaped life-forms that towered more than 25 feet above the ground. Their trunklike fossils were discovered in 1843. Yet despite more than a century of speculation, scientists have struggled to answer the most basic question about Earth’s original terrestrial giants: What were they?

The first person to examine this biological misfit did so in 1855, and in 1859 he dubbed it Prototaxites, which means “early yew.” The name stuck, even though experts soon realized the organism wasn’t a tree at all. Maybe it was some kind of land-based kelp or a megalithic mushroom? “It feels like it doesn’t fit comfortably anywhere,” says Matthew Nelsen, a senior research scientist at the Field Museum of Natural History, who was not involved in the new study. “People have tried to shoehorn it into these different groups, but there are always things that don’t make sense.”

Over time, two main hypotheses emerged: either Prototaxites was an ancient fungus, or it fell into a category all its own. Now, after comparing fossils from these cryptic organisms with fossil fungi from the same rock deposit, the authors of the new study, published today in Science Advances, conclude that Prototaxites was likely a distinct lineage. That would place it on an equal footing with the six currently recognized kingdoms of life: those of plants, animals, fungi, protists, bacteria and archaea (Note: this is a very simple, even traditional, characterization the modern phylogeny of life on earth, but it is serviceable for current purposes).

Prototaxites was composed of interwoven tubes, giving it a superficial resemblance to fungi. But the anatomical similarities end there. The researchers found that Prototaxites’ tubes branched wildly, whereas the threadlike hyphae in modern fungi follow more orderly patterns. Plus, the researchers detected no chemical trace of chitin, a polymer found in the cell walls of all living fungi and in the fossil fungi that were preserved alongside Prototaxites. “It doesn’t seem to have any of the characteristic features of the living fungal groups,” says the study’s co-lead author Laura Cooper, a Ph.D. student at the University of Edinburgh.

The paper in Science Advances states Prototaxites fossils are structurally and chemically distinct from extinct and extant Fungi (open access).  My intuition tells me the authors are correct, and that Prototaxites has “no affinity with known complex multicellular eukaryotes:

Prototaxites was the first giant organism to live on the terrestrial surface, represented by columnar fossils of up to eight meters from the Early Devonian. However, its systematic affinity has been debated for over 165 years. There are now two remaining viable hypotheses: Prototaxites was either a fungus, or a member of an entirely extinct lineage. Here, we investigate the affinity of Prototaxites by contrasting its organization and molecular composition with that of Fungi. We report that fossils of Prototaxites taiti from the 407-million-year-old Rhynie chert were chemically distinct from contemporaneous Fungi and structurally distinct from all known Fungi. This finding casts doubt upon the fungal affinity of Prototaxites, instead suggesting that this enigmatic organism is best assigned to an entirely extinct eukaryotic lineage.

But where can these very good scientists go from here?  Who knows, but the mystery will remain exciting to biology nerds everywhere as an inviting rabbit hole.

Part the Fourth: Why I Will Never Again Use “Bovine Stare” to Characterize the Typical Response from a “Dull Normal” Human Animal.  A paper published in Current Biology (open access) shows that a 13-year-old Austrian cow is an excellent tool user (videos included).  From the description in Scientific American:

In news that is sure to delight fans of a certain Gary Larson cartoon turned meme about the limitations of bovine cognition, cow tools are real.

Larson’s 1982 comic for his series The Far Side showed a cow standing behind a table bearing an array of oddly shaped objects. The text below the image read simply “cow tools.” Now a pet cow named Veronika has been documented not only using a tool but doing so in a surprisingly sophisticated way. The finding adds a new species to the growing list of creatures that have been found to use external objects to achieve a goal and suggests that society has been underestimating the minds of farm animals. (The Cow tools cartoon has its own Wikipedia page; I have the two-volume quarto edition of The Complete Far Side: 1980-1994, highly recommended but not at the current price.)

Tool use by non-human animals is well known, but this may be the first description for animals other than crows and related birds and primates.  From the Current Biology paper:

Imagine the tools a cow would make. This idea, humorously illustrated in Gary Larson’s Far Side cartoon, captures a widespread assumption: cows are neither problem-solvers nor tool users. In science, as in culture, livestock species are often cognitively underestimated, reinforced by their utilitarian role and persistent mind-denial biases associated with meat consumption. Despite over 10,000 years of domestication, research on cattle cognition remains scarce and confined to applied contexts such as productivity and welfare. Tool use, while rarely observed, offers a stringent test of cognitive flexibility. Defined as the manipulation of an external object to achieve a goal via a mechanical interface, tooling ranges from species-typical routines to innovative, problem-specific acts. We report here our experimental demonstration of flexible egocentric tooling in a pet cow (Bos taurus), Veronika, who uses a deck brush to self-scratch. Across randomized trials, she preferred the bristled end but switched to the stick end when targeting softer lower-body areas. This adaptive deployment of tool features reveals multi-purpose tool use not previously reported in non-primate mammals. Our findings broaden the taxonomic scope of flexible tool use and invite a reassessment of livestock cognition.

The broader take-home message from this research is that the “they are just dumb animals” justification for the inhumane treatment of domesticated animals in CAFOs, both mammals and birds, has is clearly mistaken, not that we needed scientific justification for this particularly evil manifestation of industrial agriculture.  From Scientific American:

As a companion animal, Veronika, now 13 years old, has lived a long life in a stimulating environment. Nötsch im Gailtal is “the most idyllic place imaginable for an Austrian cow, like straight out of The Sound of Music,” Osuna-Mascaró says. He says the family contributed to Veronika’s tool use by “providing the special conditions that enabled Veronika to express herself.” Although she learned to use tools by herself, starting with branches that had fallen from trees, Wiegele later furnished her with sticks and rakes that allowed her to perfect her scratching techniques. Most livestock animals, in contrast, live much shorter lives and spend their time in impoverished settings such as factory farms without access to objects that they can manipulate.

Now, if only human animals could be as intentionally intelligent as Veronika the Cow…

See you next week!