On the origins of the mitotic shift in proliferating cell layers

Table 1 Diverse organisms obey the constraint specified in equation ( 4)

Species name	5-sided:4-sided ratio	6-sided:5-sided ratio	7-sided:6-sided ratio	8-sided:7-sided ratio	9-sided:8-sided ratio
Drosophila	9.469	1.639	0.440	0.158	0.044
Cucumis	12.550	1.888	0.473	0.134	0.033
Xenopus	7.625	1.479	0.424	0.272	0.154
Hydra	9.938	1.748	0.450	0.184	0.044
Allium	7.550	1.364	0.439	0.260	0.319
Euonymus	9.666	1.379	0.550	0.300	0.000
Dryopteris	6.500	1.635	0.482	0.244	0.400
Anacharis (leaf, abaxial)	9.600	2.479	0.1681	0.350	0
Anacharis (leaf, adaxial)	7.286	2.235	0.2281	0.077	0
Anacharis (bud)	5.364	1.525	0.444	0.000	Undefined

For each distribution, we computed the following five ratios of cell shape frequencies: (1) pentagonal to quadrilateral frequencies, (2) hexagonal to pentagonal, (3) heptagonal to hexagonal, (4) octagonal to heptagonal, and (5) nonagonal to octagonal frequencies. Equation (4) predicts that these ratios should decrease across each row. Note that diverse organisms satisfy this condition, which corresponds to equation (4) in the text. Sample sizes for each organism are given under the heading “Sample sizes and polygonal counts by organism” in the Methods section.

ISSN: 1742-4682