(A) Log conditional mean mRNA count for a given area as a function of the log area. Each cell is sorted by area by placing it in one of 20 bins that range from the 5th to the 95th percentile. The conditional mean given the area E[m|A] is then the mean mRNA count of each bin. The area is normalised such that the average area is equal to one. Solid lines represent a least-squares linear fit to the data. 