This is a bit of ancient
evolution not often thought about but the emergence of the cellulose chain was
huge in terms of plant development. It
all became possible.
This work pushes it back to half
a billion years although I suspect much was properly developed first in the
ocean long before.
It also draws attention to the fossil
beds in this part of Atlantic Canada.
The rocks are truly ancient here.
Fossils show wood first evolved in N.B.
Scientists in New Brunswick
have discovered evidence that wood first evolved on the land the province now
occupies.
Randy Miller, the geology curator at the Museum of New Brunswick, said
the province has some of the richest fossil deposits anywhere in the world.
The new evidence pushes the origins of wood back further than
previously thought.
"This evidence shows that plants developed a woody structure about
395 to 400 million years ago. So it pushes our knowledge of that part of plant
evolution back a little more," he said.
The fossils were discovered on the Campbelton coast. North Carolina paleontologist Patricia
Gensel published the finding this week in the journal Science.
Miller said Gensel's work sheds light on life during the Devonian
period of Earth's history. It was a bleak time before animals when the tallest
plants were only knee high and clustered around rivers and marshes.
"If you were to be dropped in Campbelton you would see volcanoes;
you'd look across the landscape and there would be no trees. You'd walk down to
the river margin or the estuary margin and you'd be walking through
brush," he said.
The innovation of wood gave plants the strength and the structure to
colonize inland.
Botanist Stephen Clayden said the chance adaptation of woody cells had
important advantages for drawing more water into the plant.
"It didn't have that kind of mechanical, or conducting, plumbing
system to get water very far above the soil," he said of plant life at the
time. "The limitations were really like those of say a sponge."
The findings show the wood cells evolved first into conifers and later
the broadleaf forests that make so much of life on the planet today possible.
"Wood formation and the origin of wood formation is one of the
most significant features in the history of the Earth," Clayden said.
Gensel has promised to return the fossils to the University of New Brunswick .
The first wood fossils will be added to a collection of many more dead-end
plants and species of the period dating back nearly half a billion years.
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