Predatory plants will probably not trot over to attack us as we amble to our cars any time soon, John Wyndham’s classic sci-fi novel Day of the Triffids notwithstanding. And yet, truth may well turn out to be stranger than fiction, if we only wait. In the case of plants coming out of genetic engineering labs that wait might perhaps be 10 years – or less. In the case of mother nature, radically new tricks might require waits of 10 million or 100 million years – or more.
Spore Storm. Anthrax bacteria can kill quickly, overwhelming an animal’s natural defenses by multiplying and secreting toxins. The toxins build up in the body and they, not the organisms themselves, are what ultimately cause death. Once dead, the animal host is no longer a suitable source of food, shelter, and oxygen for the anthrax. Now something interesting happens. Some of the anthrax bacteria succeed in growing, inside their bodies, a tough cover encapsulating their genes and certain other cell components. This is called an endospore, and is capable of withstanding environmental conditions for long periods of time – several decades has been documented. When conditions finally become favorable (e.g. it is eaten by a host animal), it comes back to life, attempts to grow and divide, infects the new host, and the cycle begins anew.
Many terms derived from “spore” exist, from aeciospores to zygospores, and endospores are just one kind. Some plants reproduce via spores, ferns for example. Spores do nothing until conditions for growth are promising. Then they spring into action. Plant spores sprout into baby plants called sporelings (spores become sporelings, like seeds become seedlings). The sporelings eventually become full grown plants if all goes well. However, many familiar plants produce seeds, not spores. Seeds are much bigger and carry much more nutrition, used to give a baby plant a good start, or perhaps sustain an animal that eats it. Spores, on the other hand, are microscopic.
Oaks produce acorns, which are large seeds, not microscopic spores. But even the mightiest oak, like a tiny blade of grass, is missing a big opportunity. That is the opportunity for each cell in each leaf to create an endospore, instead of uselessly falling to the ground to rot when the leaf gets old or winter approaches. In the future, by natural accident or human design, some plant may become the first to grab that opportunity, and things may never be the same again. Instead of dropping their leaves, these plants will release a dust storm as each leaf transforms into millions upon millions of endospores, blowing in the wind. These endospores will eventually land and try to start a new plant, in the spring in temperate climates or any time in warmer conditions. Such spore-producing plants could continue to also produce seeds as they always have, but rather than waste their spent leaves along with an additional opportunity to propagate, they will instead much more efficient convert those leaves into quantities of endospores. This will give them an advantage over traditional plants, out-competing them and eventually dominating the earth, just as flowering plants have come to dominate since they first evolved at least 140 million years ago. Let us hope these superplants make useful crops. That way their domination will be useful to us.
Next Time: A Return to Roots
