Hear those crispy rice grains calling for help? Snap! Crackle! Pop!

New scientific findings are often fun and interesting, but how some "journalists" write about such things is annoying to the nth degree.  Xylem consists of a series of cellulosic tubes and during water stress, the transpirational pull upon the water columns, a force generated by water loss from leaves, can generate air embolisms.  In a manner of speaking, xylem gets the bends.  A research group has found that formation of these air bubbles makes sounds.  Now that's not all that unexpected or surprising.  Ever listen to the bubbles of carbon dioxide rising from your carbonated beverage?  That hiss you hear is the sound of all those bursting bubbles. If you had sufficiently fine listening devices, and slowed down the sounds recorded, you could probably listen to each individual bursting bubble.  Or how about the sound of air bubbles being made in a drinking straw when your sucking has lowered the level of the liquid to nearly the bottom?  Now the finding that air bubbles in the tiny xylem "straws" in a tree make a noise when forming is somewhat interesting but mostly because people don't think about trees making any noise.  Now here's where the newsy report goes seriously arwy.  It's not a "drought distress call" any more than your crispy rice cereal is calling for help to keep from drowning in the milk.  Scheesh!  This puts this report into a category of bad journalism by making a physical thing that can be explained in a non-technical way into something vaguely anthropomorphic. Was embolism too technical?  Or xylem? Where do the find these writers?  Oh, yeah, far away from science.

Plant of the week (eon?) - Cooksonia

This picture of Cooksonia is pretty remarkable. Not so much for displaying this plant's simple beauty, not even because the picture is actually in focus, but because this plant has been extinct since the Devonian some 380 million years ago.

This fossil is looking particularly good because it is a model on display in the Darwin House at the Royal Botanical Garden at Kew.

Cooksonia is significant because this is the first land plant sporophyte to show apical branching. As the axes grew, the apex divides into two equal axes, a type of branching called dichotomous. Fossils show axes of Cooksonia branching thusly 1 to 4 times. Each axis then terminating with a sporangium. This appears to be a way of getting the maximum number of dispersable offspring from a single fertilization event.

Cooksonia is also significant because at the time this was the tallest plant of its day. These axes towered some 5 centimeters (nearly 2 inches) above the substrate. It is also the earliest appearing plant to have vascular tissue, xylem, although the oldest specimens found in Silurian sediments may not have possessed true xylem.

This plant is the first step on the way to trees, and it did not really take too long for the first trees and forests to appear (near the end of the Devonian).