Different species of tarantulas mate at different times of the year. In desert areas, after a rainstorm, huge numbers of males may be seen at night, wandering around searching for females. Ground-living species enter the burrows of females to mate with them, whilst tree-living species find their mates by scent and by following the silken trails the females leave as they move.
The eggs develop in the female's body, or in an egg case which the female carries between her front legs. Up to 3,000 eggs may be laid, the larger spiders laying the most eggs. They take 2 - 3 weeks to hatch and the spiderlings spend the first few weeks of life in their mother's burrow or another safe place.
The young spiders may take many years to mature. The ones living in tropical forests take only 3 to 4 years but the American desert species can take up to 10 years.
As in all spiders, tarantulas moult their skin from time to time, as they grow.Read More: Tarantulas and humans