Females tied to tasks of building huge nests and guarding eggs for up to six months live for around 32 years, as compared to 60 years as an average lifespan for a male dragon, they said.
A research team that included scientists from the University of Melbourne along with Indonesian and Italian colleagues studied 400 individual Komodo dragons for 10 years in eastern Indonesia, their only native habitat.
The scientists said they were surprised by the significantly shorter lifespan and the smaller size of the female Komodo dragons.
Males average more than 5 feet in length while females rarely approach 4 feet, they said.
"The sex-based difference in size appears to be linked to the enormous amounts of energy females invest in producing eggs, building and guarding their nests," University of Melbourne zoologist Tim Jessop said.
"The process can take up to six months during which they essentially fast, losing a lot of weight and body condition.
"Males and females start off at the same size until they reach sexual maturity at around seven years of age. From then on females grow slower, shorter and die younger," he said in a release Wednesday.
The Komodo dragon, the world's largest lizard, is a top predator that can kill water buffalo, deer and wild boar and has also been known to kill humans.