Table 1.

Summary of the current knowledge on presence/absence of dosage balance across animals. Animal species are split to groups reflecting putative independent origins of sex chromosomes (see [29–32] for evidence on homology of sex chromosomes in dipteran insects). Most evidence was taken from the review by Gu & Walters [6], supplemented by newer data (references by the individual species in the table).

	male heterogamety		female heterogamety
dosage balance	viviparous mammals	Bos taurus	butterflies/moths	Bombyx mori
		Gorilla gorilla		Cydia pomonella
		Homo sapiens		Danaus plexippus [17]
		Macaca mulatta		Heliconius melpomene
		Mus musculus		Manduca sexta
		Ovis aries [33]		Plodia interpunctella
		Pan paniscus	brine shrimps	Artemia franciscana [18]
		Pan troglodytes
		Monodelphis domestica
	green anole	Anolis carolinensis
	swamp guppy	Poecilia picta [34]
	fruitflies	Drosophila melanogaster
		Drosophila miranda
		Drosophila pseudoobscura
	stalk-eyed flies	Teleopsis dalmanni
	Australian sheep blowfly	Lucilia cuprina
	mosquitos	Anopheles gambiae
		Anopheles stephensi
	hemipteran insects	Acyrthosiphon pisum
		Halyomorpha halys
		Homalodisca vitripennis
		Oncopeltus fasciatus
	beetle + strepsipteran insect	Tribolium castaneum
		Xenos vesparum
	roundworms	Caenorhabditis elegans
		Pristionchus pacificus
lack of dosage balance	platypus	Ornithorhynchus anatinus	birds	Charadrius alexandrinus
	brown basilisk	Basiliscus vittatus [12,13]		Corvus corone
	Burton's legless lizard	Lialis burtonis (this study)		Ficedula albicollis
	three-spined stickleback	Gasterosteus aculeatus		Gallus gallus
				Taeniopygia guttata
			Florida softshell turtle	Apalone ferox [19]
			Komodo dragon	Varanus komodoensis [16]
			caenophidian snakes	Sistrurus miliarius
				Thamnophis elegans
			tongue sole	Cynoglossus semilaevis
			blood flukes	Schistosoma haematobium
				Schistosoma japonicum
				Schistosoma mansoni