When discussing human evolution, superlatives like “oldest,” “earliest,” and “first” frequently appear in headlines. This isn’t solely to attract readers, although it often serves that purpose. Discovering evidence that a species or behavior predates previous assumptions provides valuable insight. Understanding the chronological order of events is fundamental to deciphering their causes.
For instance, the understanding that all rock art originated within the last 40,000 years implied it was created by *Homo sapiens*, as other hominin groups like Neanderthals had long since vanished. However, recent findings indicate some prehistoric art is older, opening the possibility that Neanderthals were also artists.
The past month has yielded numerous “earliest” and “first” discoveries, prompting reflection on how to interpret such findings. The crucial question arises: when can we be reasonably confident in establishing the complete duration of an artifact’s existence?
The Realm of Early Tools
Among recent finds, archaeologists at a dig in southern Greece unearthed two wooden objects, presumed to be tools. One resembles a digging stick, while the other’s precise function remains unclear. Both artifacts date back approximately 430,000 years, positioning them as the oldest known wooden tools discovered to date.
These discoveries are not drastically older than previous record-holders. The Clacton Spear, found in the UK, is estimated to be 400,000 years old, though its excavation decades ago means its dating carries inherent uncertainties. Similarly, a collection of wooden spears from Schöningen, Germany, were once thought to be of comparable age. However, more recent analyses have revised their age downward; some methods place them closer to 300,000 years old, with a study from May 2025 suggesting an age of just 200,000 years.
Bone tools have also emerged from European sites dating to this general period. In Boxgrove, UK, researchers recovered an elephant-like animal bone fragment, possibly from a steppe mammoth, fashioned into a hammer for reshaping stone tools. This elephant bone is 480,000 years old, marking the earliest known use of elephant bone in Europe. However, bone tools were utilized much earlier in other regions. In East Africa, ancient humans were systematically crafting tools from bone, including elephant bone, as far back as 1.5 million years ago. The practice may potentially extend even further back in time.
Advancements in Composite and Poisonous Technologies
Moving forward in time, an extensive collection of 2,601 stone artifacts has been documented at Xigou in central China. These artifacts, dating between 160,000 and 72,000 years ago, include hafted tools – stone components attached to other materials like wooden poles. Researchers identify this as “the earliest evidence for composite tools in Eastern Asia, to our knowledge.”
More recently, in early January, evidence emerged that people in South Africa were utilizing poison arrows 60,000 years ago. Archaeologists discovered five quartzite arrowheads coated with a sticky, poisonous substance, likely derived from plants.
Each of these discoveries offers more depth than initially apparent.
When “Oldest” Meets Preservation Limits
The designation of the oldest known wooden tools is likely not exhaustive. The primary challenge lies in preservation: wood degrades over time, resulting in a relatively sparse record of prehistoric wooden artifacts.
Katerina Harvati, who led the excavation of the wooden tools, emphasized that humans were employing wooden tools long before 400,000 years ago. The difficulty lies in locating them. Given that wood is more pliable than stone, and considering that chimpanzees are known to fashion simple wooden tools, it is plausible that wooden tools represent the earliest form of technology. The discovery of wooden tools dating a million years ago, while significant, would not be entirely unexpected, apart from the exceptional preservation required.
Consequently, significant narratives concerning human technological development should not be solely predicated on the age of the oldest wooden tools. Systematic investigation of sites with potential for preserving such artifacts across various ages is necessary for any reliable conclusions about when their use began.
Refining the Timeline of Poison Arrows and Art
Revisiting the poison arrows, these represent the oldest known examples of arrowheads with applied poison. However, the evidence suggests that arrowheads with designs consistent with modern poison arrows exist from tens of thousands of years prior. Similar to wood, poisons are subject to biodegradation.
This area allows for a degree of greater certainty. Poison arrows represent a form of composite technology—the combination of multiple components—which typically emerges in later stages of human evolution. Unlike early hominins such as *Ardipithecus* or *Australopithecus*, who might have utilized simple wooden or bone tools, there is no indication of them creating poison arrows. While the 60,000-year mark for poison arrows may not be definitive, the margin of error is likely considerably smaller.
The dating of ancient art presents a more complex challenge.
Deciphering Prehistoric Art
Cave paintings are among the most well-known forms of ancient art, alongside sculptures and engravings. A significant obstacle in studying much of this art is its difficulty to date accurately.
Sculptures found embedded in sediments can often be dated by analyzing the surrounding matrix. However, dating cave paintings is considerably more intricate. If charcoal was used in their creation, carbon dating may be applicable, but only for artifacts within the last 50,000 years; beyond this, carbon dating becomes unreliable. A substantial portion of cave art remains undated, often due to technological limitations.
Recent findings include a hand stencil in a cave in Sulawesi, Indonesia, dated to at least 67,800 years ago. This discovery makes it the oldest known rock art globally, surpassing a similar hand stencil in a cave in northern Spain, which has been attributed to Neanderthals.
The crucial caveat to these findings is the phrase “at least.” These artworks have been dated by analyzing thin layers of rock that formed over them, a process involving mineral deposition from trickling water. These “flowstones” can be dated, but this only provides a minimum age; the artwork beneath could be substantially older.
Building a Reliable Timeline
The purpose of examining these discoveries is not to suggest a lack of knowledge. On the contrary, extensive information is available, much of which was inaccessible even a decade or two ago. Instead, the aim is to explore methods for constructing a reliable timeline of human evolution and cultural development, identifying aspects inherently prone to uncertainty.
In the fossil record, sheer volume proves advantageous. Most paleontologists focus on smaller organisms like marine mollusks rather than large, charismatic animals such as dinosaurs. This is because these organisms are fossilized in vast numbers, allowing for detailed tracing of evolutionary changes. If a species is prevalent in the fossil record and then abruptly disappears around 66 million years ago, it strongly indicates its extinction at that precise juncture.
Considering the human fossil and archaeological records, what types of evidence are abundant, and what is scarce?
For many hominin species, only a few specimens exist, particularly for earlier representatives. This severely limits information regarding their lifespan and geographical distribution. It also hinders the ability to determine direct evolutionary lineages between species or more complex evolutionary processes.
In contrast, the record of stone tools is remarkably extensive. It has consistently pushed further back in time, with the Lomekwian tools from Kenya, dated to 3.3 million years ago, currently representing the oldest known. It is not improbable that even older stone tools will eventually be discovered. However, for early hominins like *Orrorin* (estimated 6 to 4.5 million years ago) and *Ardipithecus* (estimated 5.8 to 4.4 million years ago), who are believed to have spent considerable time in trees, the creation of stone tools would be an unexpected finding.
Wooden tools present a different scenario. The sample size is small and sporadic, primarily due to preservation limitations. A reliable timeline for the development of wooden tools is unlikely to emerge within the current generation.
For art, the primary constraint is technological. While preserved art is plentiful, the challenge lies in developing reliable dating methods. Currently, constructing a developmental timeline for art is not feasible, and skepticism is warranted regarding any attempts to fit it into broader narratives. However, this situation may evolve with more art being dated and the introduction of new techniques. By retirement, a more comprehensive understanding of the evolution of ancient human artistic practices is anticipated.
In essence, all narratives concerning human evolution are provisional. This applies to paleontology broadly, but some evolutionary accounts are more speculative than others. While the end-Cretaceous extinction event that eradicated non-avian dinosaurs is well-established, the human story still holds considerable room for revision. Some of these uncertainties can be resolved through the discovery of additional artifacts and the refinement of dating techniques, while others may simply need to be accepted as inherent limitations of our knowledge.