Swaying To The Top

"When the Bass brothers financed the first Biosphere, that earth in a
bubble out in Arizona, the trees all failed in an interesting way. All the
trees in the biosphere were droopy and lacked the strength to stand
upright. They grew, but were too weak to stand. They studied the problem
and found the answer. No wind. The Biosphere bubble lacked any wind so the
trees had nothing to make them sway. It was the swaying, pushing against
an invisible yet very palpable force, that gave them the strength to grow
upright, stand reaching up to the sky."
- reader of David Byrne's online journal

This is such a beautiful metaphor, and quoted on so many christian
websites, that I was afraid it would turn out not to be true. Not so. From
a transcript of PBS's Scientific American Frontiers:

ALAN ALDA You know what else I noticed that you don't seem to have- out in
this big open space, anyway- is wind.

BERND ZABEL That's correct.

ALAN ALDA That's a big element that's missing, isn't it?

BERND ZABEL Which causes a problem for these trees. When you look here,
these acacia trees, they have very funny forms. And what we found out
later on, that if a tree grows, to harden the tree it needs wind action.
Every time when a tree moves, it builds actually outside what is called a
stress wood.

ALAN ALDA So that strengthens the tree?

BERND ZABEL So it strengthens the tree. In our case here, the tree is
growing without any wind, without any disturbance, and it actually becomes
so top heavy that they break off.
- PBS Scientific American Frontiers