Maintain by picking wild-type animals raised at 25C. Heterozygotes will be wild-type and segregate wild-type, Unc, and Sterile Muv. The phenotype of homozygous lin-13 hermaphrodites segregating from a heterozygous mother depends on the temperature at which the strain was grown. At 25C, homozygous hermaphrodites segregating from a heterozygote are both Muv and sterile. At 20C, ~1/2 of hermaphrodites segregating from a heterozygote are sterile, but only a few are Muv. At 15C, hermaphrodites segregating from a heterozygote are almost wild type in appearance and fertility. However, if the progeny of these 15C animals are grown at 15C, all are sterile and some are Muv. If the progeny of these 15C animals are grown at 25C, then some animals arrest during larval growth and the rest are both sterile and Muv. Reference: Ferguson EL & Horvitz HR. Genetics. 1985 May;110(1):17-72. PMID: 3996896.