When grown in glucose-rich media, trypanosomatid parasites degrade glucose via aerobic fermentation.  In this group, this phenomenon is not a pre-adaptation to/or remnant of anaerobic life, shown through their inability to survive in anaerobic conditions.  It is believed that this phenomenon developed due to the capacity for a high glycolytic flux and the high glucose concentrations of their natural environment.  The mechanism for repression of respiration in these conditions is not yet known.