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hubie [soylentnews.org] writes:

Early crop plants were more easily 'tamed' [wustl.edu]:

The story of how ancient wolves came to claim a place near the campfire as humanity's best friend is a familiar tale (even if scientists are still working out some of the specifics). In order to be domesticated, a wild animal must be tamable — capable of living in close proximity to people without exhibiting dangerous aggression or debilitating fear. Taming was the necessary first step in animal domestication, and it is widely known that some animals are easier to tame than others.

But did humans also favor certain wild plants for domestication because they were more easily "tamed"? Research from Washington University in St. Louis calls for a reappraisal of the process of plant domestication, based on almost a decade of observations and experiments. The behavior of erect knotweed, a buckwheat relative, has WashU paleoethnobotanists completely reassessing our understanding of plant domestication.

"We have no equivalent term for tameness in plants," said Natalie Mueller, assistant professor of archaeology in Arts & Sciences at Washington University. "But plants are capable of responding to people. They have a developmental capacity to be tamed."

Her work with early indigenous North American crops shows that some wild plants respond quickly to clearing, fertilizing, weeding or thinning. Plants that respond in ways that make cultivation easier or more productive could be considered more easily tamed than those that cannot.

"If plants responded rapidly in ways that were beneficial to early cultivators — for example by producing higher yields, larger seeds, seeds that were easier to sprout, or a second crop in a single growing season — this would have encouraged humans to continue investing in the co-evolutionary relationship," she said.

[...] With erect knotweed, Mueller experienced a breakthrough of sorts. Based on four seasons of observations, Mueller determined that growing wild plants in the low-density conditions typical of a cultivated garden (i.e. spaced out and weeded) triggers plants to produce seeds that germinate more easily. This makes the harvests easier to plant successfully the next time around, eliminating a key barrier to further selection.

"Our results show that erect knotweed grown in low-density agroecosystems spontaneously 'act domesticated' in a single growing season, before any selection has occurred," Mueller said.

Think of it as the plant equivalent to that first wolf who, though still a wild animal, sat down with its human friend around the fire. This is a behavioral shift, rather than an evolutionary one, but it allows new evolutionary pathways to open up.

[...] "You can't explain plant domestication if you only consider the behaviors of humans, because domestication is the result of reciprocal relationships between multiple species that are all capable of responding to each other," Mueller said.

Journal Reference:
Natalie G. Mueller, Elizabeth T. Horton, Megan E. Belcher, Logan Kistler, The taming of the weed: Developmental plasticity facilitated plant domestication [open], PLOS, 2023. DOI: https://doi.org/10.1371/journal.pone.0284136 [doi.org]

Original Submission