Species group · Birds
WAnimals has 2 species of american sparrow, spread across 2 families (Emberizidae, Passerellidae).
Ranges calculated from the profiles that record the figure, not from all 2.
Each one has its own full profile. This group does not replace them: it brings them together.
No species documented in this group is genuinely at risk according to the IUCN, with the data available today.
Recorded in 3 countries. The ones with the most species in the group:
In practice it has four sexes: two genetic morphs, white-striped and tan-striped, that almost always pair with the opposite one, so that there are males and females of each morph and only four of the possible combinations occur in nature.
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That difference is encoded in a chromosomal inversion that behaves almost like a second sex chromosome, and each morph behaves differently: the white-striped birds are more aggressive and less attentive parents.
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Its song, a pure whistle of descending notes, is popularly transcribed in Canada as a call to the country itself and is one of the most recognisable sounds of the boreal forest.
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It is one of the model organisms of the neuroscience of vocal learning: decades of experiments on this species have established how a bird memorises a tutor's song and later reproduces it after weeks of practice.
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Its geographical variation is among the greatest of any North American bird: the forms of the Aleutian Islands weigh more than three times as much as those of the desert south-west.
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City males sing at a higher pitch than country ones to make themselves heard over traffic noise, an adjustment documented in several urban populations.
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