Would Wood Evolve?

The woods.  We call them by their primary substance: wood.  But would wood evolve from plants lacking woody stems?  Was there some evolutionary pressure to force plants to grow tall to reach the sun, so that lucky mutations found a way to produce lignin and the other building blocks of wood?  What other mutations did the blind evolutionary algorithm have to find to organize the components into trunks for trees?  Two discoveries, a fossil and a mechanism, offer evolutionists a way to enhance their woody story.

The early wood.  A fossil plant said to be 400 million years old was reported in the BBC News.  The cross-section of a stem of this early Devonian plant shows the rings of cells characteristic of wood.  The find pushes the origin of wood “about 10 million years earlier than previously thought,” said Mark Kinver, who failed to identify the thinkers (presumably evolutionists). 

Surprisingly, it appears this plant (about 8-16 inches tall) did not need wood for height.  The discoverers from the University of Liege in Belgium feel the “unexpected” woody structure “appeared to be a mechanism to transport water rather than acting as a support to allow plants to grow taller.”  Dr. Philippe Gerienne said the findings “helped shed light on the initial biological role of the woody substance in early plants” because it appears “rays (horizontal cells) most probably evolved after the other cells in wood (longitudinal cells).”  How he knew that was not explained. 

Michael Marshall at New Scientist gave an abbreviated report on this discovery, calling this the “World’s oldest wood – so far”.  Trees didn’t begin to evolve till15 million years  later, he said.  That’s a long time for plants to grow close to the ground with a structurally-strong material that could have given them height.

The paper by Gerienne’s team was published in Science.¹  The authors admitted in the abstract, “The first steps of wood evolution are unknown.”  They could only offer a suggestion: “The small size of both plants and the presence of thick-walled cells in their cortex support the earlier suggestion that the evolution of wood was initially driven by hydraulic constraints rather than by the necessity of mechanical support for increasing height.” 

On the difficulties of wood evolution, see 10/26/2001, 05/30/2008, 01/29/2009, and 12/16/2010 bullet 2.

The required mechanism.  A mechanism that drives plants upward toward the sun was described in PhysOrg.  This article ignored the E-word evolution in favor of design language: “UBC [University of British Columbia] researchers have discovered a key mechanism that — much like a construction site foreperson — controls the direction of plant growth as well as the physical properties of the biopolymers that plants produce.”

Scientists have been trying to find this design for a long time, the article indicated.  “The finding is a major clue in a 50-year-long quest to explain how plants coordinate the behaviour of millions of cells as they grow upward to compete for light, penetrate soil to obtain nutrients and water, and even open petals to flower.”  In a nutshell, the finding explains how microtubules in the cell become organized into scaffolding for cargo transportation, capture and positioning of large structures, and cell shape.

In addition to the basic cell shape acting as a guide, a protein called CLASP that “plays a key role as a foreperson, modulating the geometric constraints of the cell.”  Without CLASP, microtubules underwent “catastrophic disassembly” when encountering an edge.  CLASP enabled them to bend up to 90 degrees and continue growing in nice, parallel arrays.  Computer models confirmed what the gene knockout experiments showed.  Explained one researcher, “We confirmed that the self-organization depends on the extrinsic cues from the cellular geometry, and that the presence of the CLASP protein along select edges modified the pattern dramatically.”

Where will this finding lead?  “Microtubules and the CLASP protein are common to all cell types in plants animals, fungi and many unicellular organisms,” another researcher commented.  “So what we find out about their behaviour in plant cells is relevant to understanding their function in cells types [sic] as diverse as neurons and disease-causing protozoans.”  Of all the nerve; design-based inquiry may improve your health some day.

1. Gerienne et al., “A Simple Type of Wood in Two Early Devonian Plants,” Science, 12 August 2011: Vol. 333 no. 6044 p. 837, DOI: 10.1126/science.1208882.

One research team tried to find their way in the dark with a Darwin-brand flashlight, hoping it would shed light on evolution.  Too bad the batteries have been long dead.  How could it be otherwise?  The second law demands it for undirected processes.  The other team turned on the lights of intelligent design and found the foreman on the job, directing building blocks into functional structures.  You don’t need a dead Darwin flashlight in a well-lit factory.