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Supplemental Fig. 1. Result of hierarchical cluster analysis (also known as a heat map) of WGA-enriched proteins expressed by trophozoites and cysts. Complete linkage analysis was performed via GEPAS using a weighted pair-group method (arithmetic averages), distances were calculated using Spearman’s Correlation Coefficient Method. The resulting “heat map” clearly groups samples as either cyst or trophozoite, and the stage specific identification of individual proteins can be identified by color coding on the map (darker red = greater sample specificity). The results for abundant proteins of Giardia cysts and trophozoites were very reproducible from experiment to experiment, low abundance Giardia proteins identified by mass spectroscopy were variable from run to run. Hierarchical clustering compares the normalized abundance of proteins between individual samples (cyst vs. trophozoite), placing the same weight on both minor and major protein constituents. Due to this normalization, the resulting heat map dramatically overstate the differences between samples due to variability in runs on a particular mass spectrometer, while at the same time identifying significant clusters of proteins that are stage-specific.