ENVIRONMENT × GENETICS

The Last Mammoths

~4,000 years ago

History · Bronze Age · Holocene · Meghalayan

Mammoths outlived the ice age on one Arctic island. Rising seas cut Wrangel off around 10,000 years ago, stranding a founding herd that had passed through a severe bottleneck; genomes show the population recovering quickly, then holding steady for six millennia, purging its worst mutations while milder ones accumulated. Around 4,000 years ago, while the pyramids of Giza already stood, the line ended.

Why it matters

The last mammoths are a natural experiment in small-population survival, read at genome resolution: two hundred generations of inbreeding endured, the most lethal variants weeded out, and still extinction. For conservation genetics the lesson is double-edged: a bottlenecked species can persist far longer than feared, and remain one accident from the end. Every rescued herd and island refuge lives inside that tension.

Dating & uncertainty

Radiocarbon dates on the youngest island specimens and the genomes together place extinction around 4,000 years ago. What ended the population is unresolved: the genomes show inbreeding and a slow build-up of mildly harmful mutations, but the 2024 analysis found the herd demographically stable to near the end, so the final blow, if there was one, is still unidentified.

Sources

1. Dehasque et al. (2024), Cell · Temporal dynamics of woolly mammoth genome erosion prior to extinctiondoi:10.1016/j.cell.2024.05.033
2. Palkopoulou et al. (2015), Current Biology · Complete genomes reveal signatures of demographic and genetic declines in the woolly mammothdoi:10.1016/j.cub.2015.04.007
3. Dehasque et al. (2021), Quaternary Science Reviews · Combining Bayesian age models and genetics to investigate population dynamics and extinction of the last mammoths in northern Siberiadoi:10.1016/j.quascirev.2021.106913

Our species’ history as one day

23:41:4218 min 17 s before midnight

if the 315,000 years of Homo sapiens were compressed into a single day