Table 1. Best-fit parameters for chromosomes 3 and 5.

Chr	N	B	Ea	Bs	Be	Bd	Smax	Bsmax	A	L	cL	cR	M	T2prob
5	56	1	0.6	0.4	0.5	0.01	4.5 (15)	1	1	1 (0.54)	0.8	1.05	1	0.0095 (0.0155)
3	49	1	0.6	0.5	0.65	0.01	1 (2.03)	1	1	0.9 (0.641)	1.5	1.5	1	0.01 (0.0162)

Values in brackets are those used to achieve a 13% increase in crossovers. Chr, chromosome; N = number of precursor sites. Model parameters are defined as follows (see White et al. 2017; Zhang et al. 2014): B= Precursor distribution among bivalents (0 = Poisson, 1 = constant), E= Precursor distribution along bivalents (0 = random, 1 = even), Bs = Black hole (centromere) start position, Be= Black hole (centromere) end position, Bd= Precursor density within black hole relative to rest of bivalent, Smax= Designation driving force (Progressively increased to Smax during simulation), Bsmax= Distribution of Smax among bivalents. (0 = Poisson, 1 = constant), A= Determines distribution of precursor sensitivities. Default A = 1. L= Proportion of bivalent over which the interference signal propagates. cL / cR: End effects on interference (Left/Right) where 0 = unclamped – behaves as if there was a CO at the end of the chromosome and 1 = clamped - behaves as if there was not a CO at the end of the chromosome, M= Efficiency with which CO-designation matures to eventual CO, T2prob= Probability of a precursor site becoming a class II CO.

^aWhole chromosomes were simulated, with best-fit parameters based on Fluorescent Tagged Line-derived crossover and coefficient of coincidence values.