For much of the twentieth century, the story of human evolution was dominated by the image of early humans as increasingly skilled hunters who rose to ecological dominance through strength, intelligence, and technological innovation. Scavenging—the practice of consuming animal carcasses left behind by other predators—was often portrayed as a primitive, short-lived behavior, a temporary solution used only until hunting capabilities matured. However, a new interdisciplinary study led by the National Research Center on Human Evolution (CENIEH), with key contributions from researchers at IPHES-CERCA, challenges this long-standing narrative. Published in the Journal of Human Evolution, the research argues that scavenging was not a marginal or inferior strategy but a fundamental and recurring component of human survival throughout evolutionary history.
The study brings together an international team of scholars specializing in paleoanthropology, archaeology, ecology, and evolutionary biology. Among them are Dr. Jordi Rosell, professor at Universitat Rovira i Virgili and researcher at IPHES-CERCA, and Dr. Maite Arilla, also of IPHES-CERCA. Additional expertise was provided by researchers from CENIEH, IREC-CSIC, IPE-CSIC, Universidad Miguel Hernández, and the universities of Alicante, Granada, and Málaga. By synthesizing archaeological evidence, ecological data, and comparative studies of modern scavengers and hunter-gatherers, the authors offer a comprehensive reassessment of carrion consumption from the earliest hominins to modern humans.
Rethinking the Role of Carrion in Early Human Diets
One of the central arguments of the study is that scavenging offered clear energetic and nutritional advantages to early humans. Hunting live prey is a costly endeavor, requiring significant energy expenditure, specialized tools, coordination, and a degree of risk. Scavenging, by contrast, allowed hominins to access high-quality animal resources—meat, fat, and bone marrow—with far less effort. In environments characterized by fluctuating climates and unpredictable food availability, this efficiency would have been a decisive advantage.
The researchers highlight that carrion may have been especially important during periods of scarcity, such as droughts or ecological transitions, when plant foods and huntable animals were less abundant. Far from being a rare or desperate option, carcasses were likely a relatively predictable resource within many ecosystems. Recent ecological studies support this view, showing that animal remains are more common and accessible than previously assumed, particularly in open landscapes where large predators leave behind partially consumed carcasses.
Managing Risks and Maximizing Benefits
A common objection to scavenging has long been the perceived risk of disease and poisoning from consuming decaying meat. However, the study argues that this risk has been overstated. Many scavenger species have evolved behavioral strategies to minimize exposure to pathogens, such as selectively consuming fresher tissues or feeding quickly. Humans, the authors note, are no exception.
Biologically, humans possess an unusually acidic stomach environment, which may serve as a natural defense against harmful bacteria and toxins. This physiological trait suggests a long evolutionary history of consuming foods with higher pathogen loads, including carrion. The advent of fire and cooking further reduced these risks, allowing early humans to neutralize pathogens and extend the usability of animal resources. Cooking not only improved food safety but also increased caloric intake by making nutrients more easily digestible.
Human Adaptations That Favored Scavenging
Beyond physiology, humans were behaviorally and technologically well equipped to exploit carrion. The ability to travel long distances efficiently—an adaptation linked to bipedalism and endurance walking—enabled hominins to search wide areas for food opportunities. This mobility increased the likelihood of encountering carcasses and competing successfully with other scavengers.
Language and social cooperation also played a critical role. Communication allowed individuals to share information about food locations and coordinate group activities, reducing individual risk. Even the simplest stone tools greatly enhanced scavenging efficiency. With cutting tools, early humans could quickly access meat and marrow, resources that many competing scavengers could not exploit as effectively. Bone marrow, in particular, provided a dense source of fat and calories that was crucial for supporting larger brains and higher energy demands.
Challenging the Myth of “Primitive” Scavenging
The question of how early humans first incorporated meat into their diets has been a central debate in paleoanthropology since the mid-twentieth century. In the 1960s, archaeological discoveries in Africa revealed clear evidence that early hominins consumed animal tissue. This raised a fundamental question: were they primarily hunters or scavengers? For decades, hunting was seen as the superior and more “advanced” behavior, while scavenging was relegated to a transitional phase.
The new study decisively challenges this hierarchy. The authors point out that all carnivorous species, including apex predators, consume carrion opportunistically. Scavenging is not a sign of weakness or inferiority but a widespread and adaptive behavior in nature. Moreover, ethnographic evidence shows that many present-day hunter-gatherer societies continue to scavenge when opportunities arise, integrating carrion consumption into flexible subsistence strategies that also include hunting, fishing, and plant gathering.
Scavenging as a Persistent Evolutionary Strategy
Rather than viewing scavenging as a stepping stone toward hunting, the authors argue that it should be understood as a persistent and complementary strategy. Throughout human evolution, scavenging worked alongside hunting and gathering, providing resilience in the face of environmental uncertainty. This flexibility may have been one of the defining traits that allowed humans to spread into diverse and challenging habitats.
The study emphasizes that evolution does not favor single strategies in isolation but rewards adaptability. By exploiting a wide range of food sources, including carrion, early humans reduced their dependence on any one resource. This dietary breadth likely contributed to population stability, technological innovation, and ultimately the success of the genus Homo.
A Behavior That Helped Make Us Human
In their conclusion, the researchers argue that scavenging was far more than a marginal behavior. It was a core element of human survival that shaped our biology, technology, and social organization. By reframing scavenging as an intelligent and adaptive strategy, the study invites a broader reconsideration of what it means to be human.
Rather than defining humanity through idealized images of heroic hunters, this research highlights the importance of efficiency, cooperation, and opportunism. Eating carrion, once dismissed as a primitive habit, emerges as a practice that supported brain expansion, social complexity, and long-term survival. In this sense, scavenging did not merely accompany human evolution—it helped drive it.
Source: Catalan Institute of Human Paleoecology and Social Evolution
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