It's Friday, so time for some random, half-baked ideas. Imagine that we have a database of evolutionary trees, and these overlap for a set of taxa that we are interested in. How do we summarise these trees? One approach is to make a supertree. It would be useful to display the subtrees that went into making this supertree, if only to give an idea of how much they agree with the supertree. How to do this?
One idea I've been toying with is inspired by Photosynth, from Microsoft labs (it only runs on Windows, sigh). Photosynth takes a series of pictures taken from different angles and stiches them together into a 3D model of the object being photographed:
One thing I like about Photosynth is that you can see the original pictures, so when you move around the view you get a sense of how they have contributed to the overall view. This is easier to see than explain:
Now, imagine if we did this with trees. We could create a supertree as a summary of the individual trees, then have the original trees layered on top. Perhaps we could do this in 3D, so that each individual tree is in a plane that is tilted with respect to the supertree in proportion to how much it disagrees with the supertree:
I think this could be a fun way to explore a set of trees, and it would give one the ability to quickly grasp how well the source trees agreed with the supertree. Note that I'm not (necessarily) arguing that the supertree represents the try phylogeny. Think of it as a convenient way to summarise the individual trees.
Part of what attracts me to this approach is that I think most, if not all, 3D phylogeny viewers (such as Paloverde and the Wellcome tree of life) don't make any real use of 3D, beyond the rather gimmicky (and I find ultimately confusing) ability to fly around a 2D tree. Is there a better way to exploit the possibilities of 3D?