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Here we address the question whether the ionized shells associated with giantHII regions can be progenitors of the larger HI shell-like objects found in theMilky Way and other spiral and dwarf irregular galaxies. We use for ouranalysis a sample of 12 HII shells presented recently by Rela\~no et al. (2005,2007). We calculate the evolutionary tracks that these shells would have iftheir expansion is driven by multiple supernovae explosions from the parentalstellar clusters. We find, contrary to Rela\~no et al. (2007), that theevolutionary tracks of their sample HII shells are inconsistent with theobserved parameters of the largest and most massive neutral hydrogensupershells. We conclude that HII shells found inside giant HII regions mayrepresent the progenitors of small or intermediate HI shells, however theycannot evolve into the largest HI objects unless, aside from the multiplesupernovae explosions, an additional energy source contributes to theirexpansion.

On the origin of the neutral hydrogen supershells: the ionized progenitors and the limitations of the multiple supernovae hypothesis