Next time you see a branch don’t take it for granted. It was this simple structural addition to the first ever land plants that allowed them to thrive and colonize land.
BBSRC-funded Dr Jill Harrison and her lab are uncovering the secrets behind how branching structures evolved by inducing branching in mosses.
The image at the top shows an unbranched moss shoot with a reproductive structure at the tip.
The first land plants that appeared on earth about 450 million years ago had tiny bodies with a single reproductive shoot much like this plant.
The image below shows the same type of moss with a branch point.
The overall shape resembles the earliest branching plants which were tiny, but had a branching form that now only exists in ancient plant fossils.
Once plants learned how to branch, they were able to partition the roles of different branches on each shoot.
This allowed some branches to become specialised for photosynthesis, and eventually led to the evolution of leaves.
Jill and her team were able to induce a branching form in this plant by a simple change in hormone distribution, suggesting that the innovation of branching some 450 million years ago could have been simple.