Step back in time and get to know the world’s oldest woody plant

Fascinating new research is set to improve our understanding of how and when wood first evolved, by taking a look at the structure and chemistry of the fossilised remains of the earliest known woody plant.

Scientists at the University of Saskatchewan are using synchrotron-based technologies to travel back in time and take a closer look at Armoricaphyton chateaupannense, an extinct woody plant estimated to be 400 million years old!

The research focuses on identifying the presence of lignin, which is an organic compound found inside the tracheid cells of woody plants.

Dr Christine Strullu-Derrien, who led the research, said studies have previously been conducted on Devonian plants, but none of them were woody, making this project a world first.

"Armoricaphyton chateaupannense is the earliest known woody plant and it's preserved in both 2D form, as flat carbonaceous films, and 3D organo-mineral structures. This allows for comparison to be done between the two types of preservation," said Dr Strullu-Derrien.

One challenge associated with this kind of study is the modification of soft plant tissue that occurs with fossilisation. This alters its original biochemical structure, making it challenging to reconstruct the original chemistry with real precision.

To overcome this potential problem, the researchers utilised advanced visualisation technologies to identify lignified cells in the fossils, suggesting the plant did indeed contain an ancient version of lignin.

While the investigation has gone some way towards advancing our knowledge of when and how wood first evolved, many questions remain.

Dr Strullu-Derrien now intends to investigate whether the wood that first appeared in small plants served a different purpose than it does for today’s trees. To achieve this, her team will use the techniques harnessed during this study on plants from other geological periods to follow the evolution of their structures through time.