Category:Nude men crawling

Children (female/male)
birth until 17 years

Babies (female/male)
birth to ~24 months

Toddlers (female/male)
~2 to 4 years

Preteens (female/male)
~10 to 12 years

Adolescent children (female/male)
~13 to 17 years

Adults (female/male)
18 years until death

Young adults (female/male)
~18 to 40 years

Middle-aged adults (female/male)
~40 to 60 years

Old adults (female/male)
~60 years until death

Definitions come from, but are slightly modified from, the Physical stages of human life as found at Wikipedia:Human development (biology).