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Last summer I worked as a field botanist in western Missouri prairies, identifying plants in 100-degree weather, usually with the closest shade tree in driving distance. We were studying patch-burn grazing, a type of land management being tested by the state that would combine cattle with prescribed fire. The idea was to imitate natural cycles of megafauna and fire in an economically profitable way.

It sounds great. It was a disaster. The prairies were in a state of ruin, overrun by blackberries, sumac, and other weedy species. Likely to blame were prescribed fires repeatedly set out of season, when native plant sap was already flowing. We botanized in a state of ecological grief, frustrated that land management agencies refused to shut the program down. My boss at the time, Justin Thomas, approached me while my face was nose deep in goldenrod at Diamond Grove Prairie – a prairie that was still in decent shape, but trending downward. “Want to see a cool hybrid?” he said.

He took me to see a panic grass, a cross between Dichanthelium neuranthum and D. lanuginosum. He also showed me both parents, growing a handful of meters apart. They were all only about a foot tall. Spread out next to one another, they appeared distinct. Had I seen them on my own, I would have never known the difference.

For centuries hybrids have spellbound some botanists and intimidated many more. Often, hybridity serves as a convenient offramp for botanists having trouble with a difficult specimen or group. Weird-shaped leaf? Hybrid. Inflorescence bracts not long enough? Hybrid. “Inability to determine a specimen does not indicate hybridity,” wrote Rubus specialist Liberty Hyde Bailey in 1941.

In 1948, the botanist Edgar Anderson published “Hybridization of the Habitat” in the journal Evolution. It was the type of scientific writing that flourished then and that you’d never see in the pages of Science today: descriptive, reflective writing that is enjoyable to read. In it, Anderson made an astonishing claim: for a hybrid to thrive in nature, it must need a hybridized habitat, one that is intermediate between the two habitats of its parent species. He gave the example of irises in Louisiana, which naturally created hybrid swarms in response to ditching, pasturing, lumbering, and road-building in the 1930s. The Mississippi Delta was laid out in such a way that farmers worked long, narrow plots of adjacent land, “with almost the precision of experimental plots.” Each farmer treated his land slightly differently, creating a variety of intergrading, unfilled niches for hybrid irises to take advantage of. As the hybrids shuffled their genomes around, each of their results seemed to thrive somewhere in the immediate area. What Anderson saw in those hybrid swarms was a form of wild, spontaneous speciation enabled by humans.

This rarely happens in nature, where all ecological niches are already filled. Hybrids often display exceptionally robust traits, such as large flowers or drought resistance – a phenomenon known as hybrid vigor – but without an available niche, they tend to sputter out. “The chance that that organism does better in a stable ecosystem than one that has been evolving for millions of years is almost none,” says Benjamin Goulet-Scott, who earned a Ph.D. on phlox hybridization at Harvard. Anderson, in 1948, was proposing that human disturbance was changing the nature of plants, providing rewards for hybrids over normal sexual progeny.

Anderson’s hypothesis was largely inductive, and as Western science distanced itself from conjecture, his claim was put into the attic of scientific history. Anderson was considered a curious pioneer of ideas, but hybridization of the habitat lacked empirical support.

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When I look at the more degraded prairies of western Missouri, I see ecologies in chaos, desperately trying to make sense of disorder. Misuse and abuse have broken fundamental ecological links, and many are spinning out of control, filled with simple, generalist species scratching out harsh, annual existences devoid of mutualisms. By contrast, intact prairies in the region radiate a musical sense of interdependence. Junegrass and marsh bristlegrass sway in islands of royal catchfly and blue wild indigo. Pollinators buzz in rhythmic pulses. Even if you lack an ecological vocabulary, you can feel the harmony of functional integrity when you’re inside it. This sounds like a pagan fantasy. It isn’t. It’s hard to see in raw data, but Thomas has developed sampling indices that highlight it in summarized form. High-integrity prairies have fundamentally different trajectories than disturbed ones.

He sees the narrative in individual plants, too. Coincidentally, Thomas is a world expert on Dichanthelium, a genus of panic grasses that hybridizes readily. In this weird little specimen we were looking at, he could see the abuse of land, biological chaos, and an attempt to seek order.��

Hybridization is a short-term evolutionary gain – a way for plants to expand rapidly into new places when systems go haywire. It’s essentially spaghetti on the evolutionary wall, biology’s means of guessing at an answer on a test. “One way to think of hybridization is a massive simultaneous mutation,” Goulet-Scott says. Recent studies have shown that many invasive plants gain their invasive tendencies – like early flowering or increased seed production – through hybridization, both with native species and other non-native stock. The findings have helped spin off their own subfield of disturbance ecology. In 2014, a paper by Qinfeng Guo in Biodiversity Research finally showed empirical evidence for Anderson’s hybridization of the habitat.

Similar to mutations, the vast majority of hybrids in nature go nowhere (mules, for example, can’t reproduce). But when we bulldoze, mine, pollute, or otherwise misuse the land, they can represent a mad dash toward adaptation in a violent environment. Normal sexual reproduction – the kind you learned about in high school biology – is a slower, more stable approach to evolution, with smoother narrative arcs over deep time. When habitats change in a geologic blink, as they have done in the Anthropocene, quick and dirty adaptation is an asset.

The last century has seen a drastic increase in hybrid plants in North America, with the epicenter in New England, one of the most heavily disturbed regions on the continent. As we continue to expand our populations into the Southwest, the Southeast, and Midwest, we can expect hybrids to follow us everywhere we go.