About forty years ago Sydney Brenner began the genetic analysis of the nematode Caenorhabditis elegans. One reason he chose this animal for the study of eukaryotic development was that it was known to be a self-fertilizing hermaphrodite (i.e. a single animal makes sperm and oocytes and the oocytes are fertilized by the animal's own sperm; this is like selfing in plants ). He reasoned that the animal should be homozygous for all genetic loci (to use his phrase: "the animals are driven to homozygosity").
Prove this statement for yourself by (i) determining what the types and proportions of progeny produced in the first, third, and nth generations in a non-self-fertilizing strain starting with the mating of males and females both of which are heterozygous for a single gene (a/+) and ( ii) comparing your result with the progeny in the same generations starting with a self-fertilizing hermaphrodite that was heterozygous for a single gene (a/+).
Why would self-fertilization be a desirable property for the study of the genetic determinants of development?
In general, what properties make a "good" organism for genetic studies?