A debate has been raging amongst planetary scientists for over a decade - why are there so few exoplanets with a radius of about 1.8 times that of the Earth? Exoplanets are currently largely grouped into two distinct groups - super Earth are below that size and have rocky interiors, whereas Sub-Neptunes are above that size limit and appear puffier. But we dont really understand what about the path of planetary evolution forces this bifurcation. A new mission proposal, called the Early eVolution Explorer (EVE) wants to find out, and a draft of its concept can be found in pre-print form on arXiv.