Comparative demography of isogenic populations of Caenorhabditis elegans

Demographic characteristics of the bacterial-feeding nematode Caenorhabditis elegans were determined in two long-lived mutant strains, TJ1052 (age-1), CB4876 (clk-1), and a wild-type strain, N2. Within each strain, there was little correlation between longevity and reproduction for individuals that lived longer than 10 days. Long-lived mutant strains produced fewer eggs than the wild type. Mean total life spans were 13.2 days for the wild type, 21.9 days for age-1, and 15.8 days for clk-1; maximum life spans were 24 days for the wild type, 47 days for age-1, and 32 days for clk-1. Differences in total life span resulted primarily from longer post-reproductive survival. The mean post-reproductive life spans were longer than the wild type by 183% in age-1 and 60% in clk-1. We conclude that (i) post-reproductive survival is not correlated with egg production within isogenic populations of C. elegans, and (ii) the relationship between reproduction and longevity differs among isogenic populations with specific longevity genes. (C) 2001 Elsevier Science Inc. All rights reserved.