International Journal of Evolutionary Biology

Research Article

A Short-Term Advantage for Syngamy in the Origin of Eukaryotic Sex: Effects of Cell Fusion on Cell Cycle Duration and Other Effects Related to the Duration of the Cell Cycle—Relationship between Cell Growth Curve and the Optimal Size of the Species, and Circadian Cell Cycle in Photosynthetic Unicellular Organisms

Table 1

Ratio of the duration of the sexual cycle of the small cell and the asexual cycle, expressed as a percentage, depending on environmental conditions (k) and the relationship between the sizes of the two cells that fuse (p). Percentage below 100% indicates reduced duration of cell cycle and therefore advantage to syngamy. The rows below show the asexual cycle duration (arbitrary units) and the percentage of the cycle without growth (the plateau end of the cycle).


		k (growth rate)
		0.001	0.002	0.004	0.008	0.016	0.032

p	1	103%	105%	110%	119%	132%	148%
	1.2	89%	92%	98%	108%	122%	141%
	1.4	77%	81%	87%	97%	114%	134%
	1.6	66%	70%	76%	88%	106%	128%
	1.8	56%	60%	67%	79%	98%	123%
	2	46%	50%	58%	71%	92%	118%

Asexual cell cycle duration		713	367	193	107	63	42
Plateau percentage		3%	5%	10%	19%	32%	48%