A) affects both growth rate and bony armor of a stickleback
B) includes a DNA-binding homeodomain
C) has been duplicated repeatedly to create a whole family of variants
D) has been transferred from another organism
E) allows different populations of stickleback to interbreed

A) single alleles with major effects on life history
B) hybridization between species, producing a form that differs from both parents
C) stabilizing selection on homeotic genes
D) horizontal gene transfer between unrelated organisms
E) transposable genetic elements, or transposons

A) the effects of many genes integrated together (epistasis)
B) a homeotic mutation of a gene in the Hox cluster
C) the appearance of new genes that are paralogous with Hox genes
D) a deletion of nine nucleotides in the gemini transcription factor gene
E) horizontal gene transfer from a distantly related insect species