When I first read the new Science paper on Columbian mammoths, I laughed out loud. Not because the work was funny—it’s one of the most rigorous paleogenomics studies to come out in years—but because it felt like a perfect reminder of how slippery our definitions of life can be. We want clean categories: species, lineages, evolutionary trees branching neatly like oak boughs in the wind. Instead, we keep finding tangled knots of hybridization, divergence, convergence, and collapse. Life is messy. It refuses to stay in the lines we draw for it.
The study, led by a Mexican-European collaboration, sequenced 61 Columbian mammoth mitochondrial genomes from fossils unearthed near Mexico City. Most of those bones came from the construction site of a new airport, where tens of thousands of megafaunal remains turned up between 2019 and 2022. If you ever needed a metaphor for the future colliding with the deep past, there it is: an international hub of modern mobility rising atop the remains of Ice Age giants.
What the team found shocked the field. The Mexican mammoths formed their own distinct genetic clade, separate from Columbian mammoths further north and even from their woolly cousins. The Ars Technica headline put it bluntly: “Genetically, Central American mammoths were weird”. Weird is right. Their mitochondrial lineages were so divergent that, on paper, you might be tempted to call them a different species. But they weren’t separate in the way we usually imagine species. They overlapped in time with northern mammoths, interbred, and still maintained their own genetic signatures. The boundaries blurred. Identity was more fluid than fixed.
This brings me back to the Seven Moonshots for the Century of Biology. One of those moonshots—the Paradigms of Life—asks us to confront a deceptively simple question: what counts as life, and how do we define its categories? For a long time, biology pretended the answers were settled. A species is a species. An organism is an organism. A cell is a cell. But every advance—from viruses to CRISPR babies to synthetic genomes—erodes that confidence. Mammoths, it turns out, are just the latest teachers.
What’s striking about this particular mammoth study is not just the discovery of a new lineage, but what that lineage represents. Here were animals living thousands of miles from their Arctic cousins, adapting to warmer climates, carrying with them the ghost signatures of ancient hybridization events. And yet they weren’t collapsing under that genetic messiness—they were thriving. In fact, the study suggests that Mexican mammoths may have represented entire social groups, with males and females preserved together, rather than isolated wanderers. They weren’t evolutionary accidents. They were communities, living within—and shaped by—the complexity of their genetic inheritance.
That insight matters because it pushes us to reconsider the metaphor of the evolutionary tree. For over a century, we’ve sketched life as a branching diagram, each split representing a tidy moment of divergence. But the more genomes we sequence—ancient or modern—the more those clean forks blur into networks. Admixture and introgression are not exceptions; they are the rule. Mammoths remind us that life’s history looks less like an oak tree and more like braided rivers, crossing and rejoining, carving new paths across time.
And isn’t that the challenge we face today in synthetic biology, AI-driven biotechnology, and embryo editing? We keep trying to draw lines, and life keeps finding ways to smudge them. Manhattan Genomics didn’t launch to debate whether embryos could be edited; they launched to do it. OpenAI and Retro Biosciences didn’t train a model to simulate cell identity—they trained it to reprogram it. We are no longer standing outside the tree of life as observers. We are splicing branches, rerouting rivers, and stitching together genomes with the same kind of hybridity that shaped mammoths.
The Mexican mammoths lived at the edge of their species’ range, in climates far warmer than the tundra steppe. That edge is often where you find novelty. Populations isolated by geography or ecology accumulate differences, sometimes so profound that they force us to rethink evolutionary narratives. Today, our frontier is not geographic—it’s technological. And the same principle holds. As we push biology into new domains—fusion of human and machine, synthetic cells, reprogrammed identities—we will discover lineages of thought and practice that look, to our descendants, as strange as Clade 1G mammoths do to us.
Here’s the provocation: maybe we’ve been asking the wrong question. Instead of demanding that life fit into our definitions, perhaps the moonshot is to design definitions that fit into life. A science that accommodates hybridity, admixture, and emergence without forcing them into boxes. A policy framework that acknowledges the messiness without using it as an excuse for paralysis. A culture that can live with blurred boundaries instead of running back to false certainties.
To make that shift, we’ll need tools—not just genomic sequencers and AI models, but intellectual tools that allow us to live with ambiguity. We’ll need to teach the next generation of biologists, engineers, and policymakers that fluidity is not failure, and that embracing complexity is the only way to navigate the future we are building. We’ll need to invest in frameworks like Violet Teaming—responsible innovation exercises that stress-test technologies against unintended consequences—so that our expanded paradigms of life don’t collapse into unexamined risks.
The mammoths are gone, but they leave us this lesson: categories are conveniences, not truths. In the century of biology, our challenge is to embrace that fluidity without losing our bearings. If we succeed, the Paradigms of Life moonshot won’t just redefine biology—it will reshape how we understand ourselves. The story of mammoths isn’t just about extinction. It’s about survival through complexity. And maybe that’s the lesson we most need to carry forward as we stand at the edge of our own evolutionary frontier.
Onward to complexity,
—Titus
