4. Crossing-over

15. Calculation of chi-square χ 2 = 1,489.99 3,236 3,236 Total 398.79 322,624 -568 809 241 Black-vestigial 458.44 370,881 609 809 1,418 Back-normal 290.76 235,225 485 809 1,294 Grey-vestigial 342.00 276,676 -526 809 283 Grey-normal D 2 /E D 2 Deviation (D) Expected number (E) Observed number (O) Phenotypes

27. 5 v + cv ct + 8 3 v cv + ct 7 94 v + cv + ct + 6 89 v cv ct 5 40 v + cv + ct 4 45 v cv ct + 3 592 v + cv ct 2 580 v cv + ct + 1 Number observed Genotype Class

30. Recombinants (double crossovers) 5 v + ct + cv 8 Recombinants (double crossovers) 3 v ct cv + 7 Recombinants (single crossovers in region v – ct) 94 v + ct + cv + 6 Recombinants (single crossovers in region v – ct) 89 v ct cv 5 Recombinants (single crossovers in region ct – cv) 40 v + ct cv + 4 Recombinants (single crossovers in region ct – cv) 45 v ct + cv 3 Parentals 592 v + ct cv 2 Parentals 580 v ct + cv + 1 Type Number observed Genotypes Class

32. Genetic linkage map of the v ct cv region of the chromosome