Thus a pair of brown rats can produce as many as 2,000 descendants in a year if left to breed unchecked. (A rat matures sexually at age three to four months.) An average rat's life span is two to three years.5 A rat can tread water for three days and survive being flushed down the toilet.hus a pair of brown rats can produce as many as 2,000 descendants in a year if left to breed unchecked. (A rat matures sexually at age three to four months.) An average rat's life span is two to three years.
Late lice. The common head louse, Pediculus humanus capitis, may take as long as 14 days to hatch. Gilles San Martin/Wikimedia Commons. Hereâs some lousy news for parents of itchy-headed kids: Lice eggs can take 2 weeks to hatch in human hair, making standard 7-day delousing treatments ineffective in some cases.
Pubic lice have three forms: the egg (also called a nit), the nymph, and the adult. Nit: Nits are lice eggs. They can be hard to see and are found firmly attached to the hair shaft. They are oval and usually yellow to white. Pubic lice nits take about 6â10 days to hatch.Nymph: The nymph is an immature louse that hatches from the nit (egg). A nymph looks like an adult pubic louse but it is smaller. Pubic lice nymphs take about 2â3 weeks after hatching to mature into adults capable of reproducing.ubic lice have three forms: the egg (also called a nit), the nymph, and the adult. Nit: Nits are lice eggs. They can be hard to see and are found firmly attached to the hair shaft. They are oval and usually yellow to white. Pubic lice nits take about 6â10 days to hatch.