  We find no evidence for the presence of genuinely young galaxies in our Local
universe. We argue that the metal deficiencies and the behavior of the N/O and
C/O ratios meet several plausible explanations involving the primary and
secondary nature of these elements and their dispersion and mixing by massive
stars and intermediate mass stars. Colors are to be analysed using surface
photometry and comparing several model scenario since an instant burst model
unavoidably provides a lower limit to the age. Ultimately colour-magnitude
diagram techniques will be the only direct test to be performed at least on a
small number local starburst galaxies. Our present analysis provides important
warning for assessing the true age of distant galaxies.
