Table 1.

Model syllables in the repertoires of canaries in different genetic groups. As group number increases, so does the genetic contribution of border relative to roller strains, either through autosomes or sex chromosomes.

groupa	N	Z chromosomes	autosomesb		group-characteristic imitationsc		rarer imitationsc		absent imitationsc
			%R	%B	low tours	high tours	low tours	high tours
1. RR	5	ZRZR	100	0	a b2c1c2deh no		b1fgijkm		l (+25 high tours)
2. BR-R	9	ZRZR	75	25	b1b2c1c2d m		a    e hijklmno	BCDEF ILMN	fg (+16 high tours)
3. RB-R	9	ZBZR	75	25	a b2c1	ABCDEFGIJKLMNO   WXY	b2 c2dehijklmno	H PQRSTUV	fg
4. BR, RB	9	ZBZR	50	50	a b2	ABCDEFGIJKLMNO   VWXY	b1 c1c2de hikmno	H PQRSTU	fgjl
5. BR-B	14	ZRZB	25	75		ABCDEFGHIJKLMNOPQR  VWXY	ab1b2c1 d   mn	STU	c2 efghijklo
6. RB-B	7	ZBZB	25	75		ABCDEFGHIJKLMNOPQRST   WXY	ab1b2c1c2dk no	UV	efghijlm
7. BB	5	ZBZB	0	100		ABCDEFGHIJKLMNOQ   XY	b2 c2	PRSTUVW	ab1c1defghijklmno

^aLetters indicate strain (R, roller; B, border) of mother, then father. Hyphenated groups are comprised of backcrosses: each individual is the offspring of a hybrid female and a purebred roller or border.

^bZ chromosomes are known from the backcross design; autosomes are average values derived from pedigrees.

^cLow tours are roller syllables, shown as lower case letters; high tours are Norwich syllables, shown as upper case letters. In two cases, pairs of syllables were distinct but similar in structure to each other; these are treated separately but marked with subscripts. A total of 16 high tours and 25 low tours were presented as models to all individuals. Group-characteristic imitations were learned by at least 75% of individuals in the group. Underlined group-characteristic syllables were not learned by one individual in the group. Syllables are spaced to align them for visual comparison across genetic groups.