Burning Plants Tell Seeds When to Germinate
Forest fire ash is not all useless. It contains signaling molecules that can switch on the next generation of plants.
How is it that in the spring following a forest fire, the ground comes alive with a profusion of new seedlings? How do the seeds, which may have lain dormant in the soil for years, know that the ground has been cleared, providing opportunities for a new generation of growth?
An open-access paper in PNAS describes how a molecule in the ash of plants after a forest fire turns on growth in dormant seeds. According to the paper, “Germination-stimulating compounds, generated in the smoke of burning plants, include a seed dormancy–breaking compound” called karrikin-1. The scientists studied what this molecule does to a seed. Inside the seed is a protein, KAI2, that has a receptor for karrikin-1. When the key fits the lock, the protein changes shape, switching on a message cascade that tells the side to prepare for sprouting.
A Salk Institute press release,”Smoke signals: How burning plants tell seeds to rise from the ashes,” summarizes the findings:
“This is a very important and fundamental process of ecosystem renewal around the planet that we really didn’t understand,” says co-senior investigator Joseph P. Noel, professor and director of Salk’s Jack H. Skirball Center for Chemical Biology and Proteomics. “Now we know the molecular triggers for how it occurs.”
Noel’s co-senior investigator on the project, Joanne Chory, professor and director of Salk’s Plant Molecular and Cellular Biology Laboratory, says the team found the molecular “wake-up call” for burned forests. “What we discovered,” she says, “is how a dying plant generates a chemical message for the next generation, telling dormant seeds it’s time to sprout.“
The original paper didn’t say anything about how evolution produced this signaling system, but the press release took a stab at it:
“In plants, one member of this family of enzymes has been recruited somehow through natural selection to bind to this molecule in smoke and ash and generate this signal,” says Noel, holder of Salk’s Arthur and Julie Woodrow Chair and a Howard Hughes Medical Institute investigator. “KAI2 likely evolved when plant ecosystems started to flourish on the terrestrial earth and fire became a very important part of ecosystems to free up nutrients locked up in dying and dead plants.”
The researchers never explained how this recruitment “likely evolved.” It was just “somehow.”
Another article on Live Science about plant ecology states that aerosols produced by plants can modulate global climate. “Plants release gases such as water vapor and oxygen; these combine with the aerosols released from plants to form larger airborne particles that reflect sunlight and form cloud droplets.” The pleasing scent of a forest comes from these aerosols.
The Salk press release provides a good example of how evolution pretends to be scientific while only gesticulating (hand-waving) in fantasyland. The science about karrikins and KAI2 has nothing to do with evolution; it’s just good old observational, reproducible experimentation. The evolution stuff was just tacked on at the end. But look at it! An enzyme has been “recruited somehow through natural selection,” we are told. OK, how? “Somehow.” It just evolved. How do you know it evolved? It “likely evolved.” Is this somehow likely? No; it’s not even likely somehow. Proteins and enzymes are highly complicated living machines that defy origin by chance (see online book).
But even if in someone’s wildest imagination KAI2 “emerged” somehow, unlikely as it is, getting it to do anything requires a whole system of other proteins, enzymes and genes to interact with it for a functional purpose. When these scientists asserted it is “somehow…likely” that natural selection (an aimless, purposeless process) accomplished this without meaning to, they did BAD (Bald Assertion of Darwinism). They abandoned all pretense of science. They are just gesticulating, speculating, confabulating, somnabulating, absquatulating out of their own imaginations, where miracles of emergence happen when they wish upon a star.
Everyone, therefore—even Darwinians—believes in miracles and the supernatural. Some can defend their beliefs with reason and evidence. Others, like these Darwin addicts, just blow smoke and hot air.