This dataset is associated with the preprint publication: https://doi.org/10.1101/2023.01.13.523799. Summary: The dataset has information about Heliconius erato demophoon butterflies fed for 14d (young, Y) and 45d (old, O) on three different diets: sugar only (NP); sugar + supplement (C); sugar + pollen from flowers (F). These experiments were set up with 8 males and 8 females of similar size (~3 cm of forewing radius) per treatment (diet/age). At the end of the experiment, females were individually assay for fertility: number of laid eggs recorded and the total eggs per females collected for quantification of cyanogenic glucoside(CG) with target-metabolomic (HPLC-MS/MS). All butterflies were also weighted and collected for target metabolomics at the end of the experiment. The main folder of these data set contains this .txt file, as well as one .csv file, one .R file, and one directory. The file Pollen_R_dataset.csv has all the fitness measurements analysed in this experiment. Each column name corresponds to a variable, with the name of the variable in the first row (all other rows correspond to samples): “ID” is the name of the butterfly sample (unique value); “Diet” is the diet fed to the butterfly (3 groups: sugar; sugar + CCF; sugar + flowers); “Age” is the age group of each butterfly at sampling based on days after eclosion (3 groups: 0d; 14d; and 45d); “Weight” is the butterfly weight in mg (numerical variable); “linT” is the total content of the CG linamarin in ug per butterfly sample (numerical variable); “lotT” is the total content of the CG loutaustralin in ug per butterfly sample (numerical variable); “elotT” is the total content of the CG epilotaustralin in ug per butterfly samples (numerical variable); “totalT” is the total CG content in ug per butterfly and correspond to the sum of linT, lotT and elotT (numerical variable); “eggs” is the number of laid eggs per each females in the 48h oviposition assay (numerical variable); “olinT” is the total content of the CG linamarin in ug per egg sample (numerical variable) (“ovo” means egg in Portuguese, therefore the content of compound in egg samples starts with o); “olotT” is the total content of the CG loutaustralin in ug per eggs sample (numerical variable); “oelotT” is the total content of the CG epilotaustralin in ug per egg sample (numerical variable); “ototalT” is the total CG content in ug in egg samples and correspond to the sum of olinT, olotT and oelotT (numerical variable); AND “ototalO” is the total CG content in ug in egg samples (“ototalT”) normalized by the number of eggs in each sampels (“eggs”). The file “Pollen_R_script.R” correspond to the R script used for making all the plots and statistical analyses reported in the preprint https://doi.org/10.1101/2023.01.13.523799. The script uses the file Pollen_R_dataset.csv as dataset. The directory “Raw chemical data” has many folders (.d format) and each folder is a HPLC-MS/MS sample. This includes biological samples, as well as, standards (St) and blanks. The samples folders are named as “sample ID”_“position in the auto-sampler=1-108”_”number of injections=1”_”position in the running (unique value).d”, for example “yN16_62_1_1523.d”. Each samples folder needs to be opened using the paid software Bruker Compass DataAnalysis software (available in https://bruker-compass-dataanalysis.software.informer.com/). The directory “Raw chemical data” also contains the excel file “target metabolomics” that shows how the content of each CG in each samples was calculated. This file has a sheet called “LCMS_raw” showing the calculations per sample, and a sheet called “Standards” showing the calibration curves. The total amount of each compound in the sheet “LCMS_raw” was estimated based on their extracted ion chromatogram (EIC) peak areas and quantified based on calibration curves in the sheet “Standards”. The original formulas used in the calculation where inserted in each column. All cyanogenic glucosides in the biological samples were identified based on the retention time (RT) mass/charge (m/z) of their Sodium Adducts [M+Na]- in comparison with authentic standards. Linamarin = RT 2.8 min, [M+Na]- at m/z 270; Lotaustralin = RT 4.0 min at m/z 284; Epilotaustralin = RT 4.3 min m/z 284; AND Amygdalin (internal standard) = RT 4.8 min at m/z 480. For information on the HPLC-MS/MS condition, please check the original publication.