“Convince me that you have a seed,” wrote Thoreau, “and I am prepared to expect wonders.”
To wet your appreciation for some of those wonders, go to a grocery store and look at all the foods that come from seeds. The isles are full of them. Or just plant a seed and watch it grow. The charm is catching, as any gardener can tell you.
George Bernard Shaw was impressed by the “fierce energy” concentrated in a seed. Put an acorn in the ground, he says, and it “explodes” into an oak tree. The wonder is that something so small and so seemingly lifeless can transform itself into a beautiful flower or a magnificent tree.
Biologist Carol Baskin describes the seed as a “baby in a box”. The “box” is a seed coat, the “baby” is a plant embryo, and the box comes packed with a lunch of starches, oils and other nutritive tissues. The food is there to feed the growing embryo until it can fend for itself.
But no sooner than the seeds appeared, animals started eating them too. The plants responded by making more seeds, and more seeds meant more animals to feed on them. This dance between animals and seed plants started with the arrival of the angiosperms 125 million year ago, and it greatly accelerated the pace of evolution.
Humans, too, developed an intimate relationship with seeds. The transition from hunting-gathering to planting and cultivating laid the foundation of civilization. Our paleolithic ancestors changed the character of the seeds, and the seeds shaped the habits and character of man.
It was a taste for seeds that spawned the age of exploration. The arrival of spices in Europe in the fifteenth century opened trade routes to Asia, and Columbus and Magellan set sail on their historic voyages in search of a more direct trade route to the Spice Islands.
Seed plants also played a role in some important scientific discoveries. Gregor Mendel’s experiments with peas gave us our first understanding of heredity, and Darwin’s finches on the Galapagos Islands provided insight into the theory of evolution. The finches happened to have different beaks for eating different kinds of fruits and seeds, causing Darwin to search for an explanation.
Today 70 percent of the land on Earth is under cultivation and grains such as wheat, corn and rice account for more than half the human diet. Grasses and grains also produce most of our nonvegetable foods such as pork, beef and poultry.
The energy stored in seeds is indeed fierce. It is true that fossil fuels produce more energy, but the seeds have a hidden advantage. They are renewable, and fossil fuels are not. Burn fossil fuel and it’s gone forever. Plant a seed and it makes more seeds.
Wheat averages about 22 seeds per head and 5 heads per plant, which amounts to about 110 seeds in total. That means one grain of wheat can produce more than 100 times more seeds than it started with. And it only takes one seed to grow a new plant.
In just two generations, assuming all the seeds are fertile, the first 100 seeds will be multiplied by another 100, giving a total of 10,000 seeds. The amount of energy created is staggering. If that’s not fierce, I don’t know what is.
Of course, the food is made in the plant by photosynthesis, but it is the seed that makes the plant that makes the food.
Perhaps equally important as storing food is the seed’s ability to go into dormancy, which is a kind of suspended animation. The embryo in the seed is primed to go at any moment, but it will germinate only under the right conditions.
Dormancy gives the seed a unique ability to travel across time. Seeds can reman dormant for months, years or decades, and even for centuries. The seed of a date palm germinated after lying dormant for nearly 2000 years.
Without an ability to go dormant, the seed would soon die and so would many of the plants, and there would be no surplus of seeds and grains to feed people, to grow a civilization or to support the world’s ecosystems.
Dormancy makes plants less susceptible to catastrophic changes in climate. The angiosperms survived and continued to diversify in the mass extinction 65 million years ago that killed off 70 percent of all species. What likely kept the plants alive was the ability of their seeds to go dormant during the long period of darkness thought to be caused by an asteroid impact.
Something similar happens on a smaller scale every winter. Seeds survive the cold dark months of winter by going dormant. In little pieces of concentrated energy, they maintain a vital link between generations. Seeds are the true keepers of life.
Gardeners are probably poring over their seed catalogues now, eager to get their hands in the soil though planting time is still weeks away. They know, perhaps more than anyone, it’s not the flowers and vegetables that make a lush summer garden. It’s the seeds.
Richard Weber is a nature enthusiast
living in Ellis County.