The age of humans is a complex question with multiple interpretations depending on what aspect of "human" is being considered. There's no single definitive answer.
The Evolutionary Age of Hominins
The evolutionary history of hominins, our lineage, stretches back millions of years. Evidence suggests hominins first appeared around 6 million years ago during the Miocene epoch. [^1] This encompasses a long period of evolution leading to modern Homo sapiens.
The Age of Homo sapiens
Modern humans, Homo sapiens, have been around for approximately 200,000 years. [^2] This timeframe marks the emergence of our species and the subsequent development of complex cultures and societies. The Paleolithic period, lasting from roughly 2.5 million years ago to 10,000 BC, encompasses the earliest human technologies and survival strategies. [^9]
The Anthropocene: The Age of Human Impact
The Anthropocene, an unofficial geological epoch, highlights the significant impact humans have had on the Earth's geology and ecosystems. While Homo sapiens has existed for 200,000 years, the Anthropocene is a relatively recent period representing the substantial alteration of Earth's systems due to human activities. [^2, ^4, ^7, ^8] This impact is significant, even though modern humans have only been around for a fraction of Earth's 4.5 billion-year history. [^2]
Comparing Human and Animal Lifespans:
It's important to note that comparing human age to other species, such as mice, requires sophisticated biological and statistical methods. Studies examining age equivalence often focus on lifespan comparisons and biological factors to estimate equivalent ages. [^5, ^10]
In summary: The "age of humans" depends on the context:
- Evolutionary age of hominins: ~6 million years
- Age of Homo sapiens: ~200,000 years
- Anthropocene (age of human impact): A relatively recent and ongoing period.
[^1]: Hominins first appear by around 6 million years ago, in the Miocene epoch, which ended about 5.3 million years ago. Our evolutionary path takes us through the Pliocene, the Pleistocene, and finally into the Holocene, starting about 12,000 years ago. (Source: https://humanorigins.si.edu/research/age-humans-evolutionary-perspectives-anthropocene)
[^2]: The Earth is 4.5 billion years old, and modern humans have been around for around a mere 200,000 years. Yet in that time we have fundamentally altered the… (Source: https://www.nhm.ac.uk/discover/what-is-the-anthropocene.html)
[^4]: “After Preservation asks one of the big, hairy, audacious questions of the early twenty-first century: How should humans relate to Nature in the Anthropocene? (Source: https://press.uchicago.edu/ucp/books/book/chicago/A/bo20298998.html)
[^5]: Equivalent ages between rodent and human have been defined by comparing survival rates between mice and humans over their lifespans. For example, one study… (Source: https://pmc.ncbi.nlm.nih.gov/articles/PMC5367550/)
[^7]: Unsettled Nature: Artists Reflect on the Age of Humans… (Source: https://naturalhistory.si.edu/exhibits/unsettled-nature-artists-reflect-age-humans)
[^8]: Living in the Age of Humans (Source: https://storymaps.arcgis.com/collections/cf8b6867ad954a6e9ed400ca9e9206ea)
[^9]: In the Paleolithic period (roughly 2.5 million years ago to 10,000 B.C.), early humans lived in caves or simple huts or tepees and were hunters… (Source: https://www.history.com/news/prehistoric-ages-timeline)
[^10]: Does age matter? The impact of rodent age on study outcomes - PMC (Source: https://pmc.ncbi.nlm.nih.gov/articles/PMC5367550/)
