When people started to plant stored seed
stock deliberately, they also began protecting their plant. This changed the
evolutionary pressure that these food plants experienced, as they no longer had
to survive in a natural environment. Instead, people created a new environment
for them, and selected for other characteristics than what nature previously
had. Seeds recovered at archaeological sites clearly show that early farmers
selected for larger seeds and thinner coats. Thick, impermeable seed coats are
often essential for seeds to survive in a natural environment, because the
seeds of many wild plants remain dormant for months until winter is over and
rain sets in. But under human management thick seed coats are unnecessary, as
farmers take over responsibility for storing seeds away from moisture and
predators. In fact, seeds with thinner coats were preferred as they are easier
to eat or process, and they allow seedlings to sprout more quickly when sown.
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