title: Why do organisms produce gametes of only two different sizes? Some theoretical aspects of the evolution of anisogamy.
mesh_terms: D056890:Eukaryota / Q000235:genetics; D005787:Gene Frequency; D005838:Genotype; D005854:Germ Cells / Q000166:cytology*; D008957:Models, Genetic; D010312:Parthenogenesis; D011110:Polymorphism, Genetic