Biology
for Fruit Fly
Fruit flies pass through four life stages: egg, larva (maggot), pupa, and adult. Source: https://ipm.ucanr.edu/PMG/GARDEN/FRUIT/PESTS/fruitflies.html The cycle is fast. UGA Extension reports egg-to-adult development in about a week, with a female laying up to about 500 eggs. Source: https://site.extension.uga.edu/madison/2021/08/shoo-fruit-flies-dont-bother-me/ Figures vary by source: UC IPM's strawberry vinegar fly data puts egg output higher at 700 to 800 over a lifespan of about 7 to 8 days in summer, lengthening to 20 to 30 days when cooler — fast enough for a few flies to become many. Source: https://ipm.ucanr.edu/agriculture/strawberry/vinegar-fly/