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The details of bulge formation via collapse, mergers, secular processes ortheir interplay remain unresolved. To start answering this question andquantify the importance of distinct mechanisms, we mapped a sample of threegalactic bulges using data from the integral field spectrograph WiFeS on theANU 2.3m telescope in Siding Spring Observatory. Its high resolution gratings(R=7000) allow us to present a detailed kinematic and stellar populationanalysis of their inner structures with classical and novel techniques. Thecomparison of those techniques calls for the necessity of inversion algorithmsin order to understand complex substructures and separate populations. We useline-strength indices to derive SSP-equivalent ages and metallicities.Additionally, we use full spectral fitting methods, here the code STECKMAP, toextract their star formation histories. The high quality of our data allows usto study the 2D distribution of different stellar populations (i.e. young,intermediate, and old). We can identify their dominant populations based onthese age-discriminated 2D light and mass contribution. In all galactic bulgesstudied, at least 50% of the stellar mass already existed 10 Gyrs ago, morethan currently predicted by simulations. A younger component (age between 1 to8 Gyrs) is also prominent and its present day distribution seems to be affectedmuch more strongly by morphological structures, especially bars, than the olderone. This in-depth analysis of the three bulges supports the notion ofincreasing complexity in their evolution, likely to be found in numerous bulgestructures if studied at this level of detail, which cannot be achieved bymergers alone and require a non-negligible contribution of secular evolution.

Dissecting galactic bulges in space and time I: the importance of early formation scenarios vs. secular evolution