The Evolution of Self-Fertilization

Arabidopsis thaliana (pictured) is the dry erase board of plant biology; which is to say it's a good model organism. We know a lot about it, not because it's particularly useful or interesting to humans, but because it's very easy to study. It has a short life cycle (six weeks), it's allegedly easy to grow (although I, personally, suck at it), you can grow a lot of it in a very limited amount of space, it has a small, fully-sequenced genome and it self-fertilizes. A paper published in last week's Nature explores how Arabidopsis' capacity for self-fertilization evolved.

Convergent Evolution in Lignin

Lignin is a rigid, waterproof polymer found only (as far as I know) in plant cell walls.  It's pretty interesting stuff: it's what makes trees rigid enough that they don't fall over and gives the water-bearing vessels in plants the ability to withstand large tensions without caving in. It's also inedible, at least to animals, and is sometimes used as a defensive compound. Because it's of economic significance (high-lignin wood makes good building material and fuel, but bad paper) a fair bit is known about it biochemically.

Why do I, an evolutionist, care? Because of this cool paper recently published in Plant Cell.