Variable blue stragglers have recently been used as distance indicators for globular clusters (McNamara, 2001). Assuming a metallicity similar to that of the globular cluster itself, their ages can be determined through their Period-Luminosity relation and their effective temperatures. The results show them much younger than the globular clusters in which they are embedded. This favors the assumption of a blue straggler being the result of a merging of two stars.
On the other hand, the EASE scenario (Jehin et al., 1999) foresees the presence of some extremely metal-poor stars in all the globular clusters. Using this assumption on their metallicity, some of the variable blue stragglers are found much older, with an age comparable to that of the globular clusters.

 
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