Editing Copepod (section)

===Life cycle===
[[File:Mikrofoto.de-ruderfusskrebs10.jpg|thumb|left|Egg sac of a copepod]]
Most nonparasitic copepods are holoplanktonic, meaning they stay planktonic for all of their lifecycles, although harpacticoids, although free-living, tend to be benthic rather than planktonic.
During mating, the male copepod grips the female with his first pair of antennae, which is sometimes modified for this purpose. The male then produces an adhesive [[spermatophore|package of sperm]] and transfers it to the female's genital opening with his thoracic limbs. Eggs are sometimes laid directly into the water, but many species enclose them within a sac attached to the female's body until they hatch. In some pond-dwelling species, the eggs have a tough shell and can lie dormant for extended periods if the pond dries up.<ref name=IZ/>

Eggs hatch into nauplius larvae, which consist of a head with a small [[telson|tail]], but no thorax or true abdomen. The nauplius moults five or six times, before emerging as a "copepodid larva". This stage resembles the adult, but has a simple, unsegmented abdomen and only three pairs of thoracic limbs. After a further five moults, the copepod takes on the adult form. The entire process from hatching to adulthood can take a week to a year, depending on the species and environmental conditions such as temperature and nutrition (e.g., egg-to-adult time in the calanoid ''Parvocalanus crassirostris'' is ~7 days at {{convert|25|C|F}} but 19 days at {{convert|15|C|F}}.<ref>{{cite thesis |first=Thomas D. |last=Johnson |year=1987 |title=Growth and regulation of a population of ''Parvocalanus'' ''crassirostris'' in Long Island, New York |type=Ph.D. Diss |publisher=SUNY Stony Brook |oclc=19047124 }}</ref>