Here's a general idea:
* Some species grow relatively quickly, adding several centimeters per year in their early stages.
* Others grow much slower, particularly in colder waters or with limited food sources.
* Most starfish reach sexual maturity after a few years.
* Their lifespans also vary, ranging from a few years to several decades.
Here are some specific examples:
* The common starfish (Asterias rubens) can grow up to 10 cm in diameter in its first year.
* The crown-of-thorns starfish (Acanthaster planci) can grow up to 30 cm in diameter in a few years.
Factors influencing growth rate:
* Temperature: Warmer waters generally support faster growth.
* Food availability: Ample food allows for faster growth.
* Predation: Starfish that are frequently preyed upon may grow faster to reach a size where they are less vulnerable.
If you're interested in the growth rate of a specific species, it's best to consult scientific literature or experts in marine biology.