  Several models compete to explain the abundance properties of stellar
populations in globular clusters. One of the main constraints is the
present-day ratio of first- and second-generation stars that are currently
identified based on their sodium content. We propose an alternative
interpretation of the observed sodium distribution, and suggest that stars with
low sodium abundance that are counted as members of the first stellar
generation could actually be second-generation stars. We compute the number
ratio of second-generation stars along the Na distribution following the fast
rotating massive star model using the same constraints from the well-documented
case of NGC 6752 as in our previous developments. We reproduce the typical
percentage of low-sodium stars usually classified as first-generation stars by
invoking only secondary star formation from material ejected by massive stars
and mixed with original globular cluster material in proportions that account
for the Li-Na anti-correlation in this cluster. Globular clusters could be
totally devoid of first-generation low-mass stars today. This can be tested
with the determination of the carbon isotopic ratio and nitrogen abundance in
turn-off globular cluster stars. Consequences and related issues are briefly
discussed.
