[2][3][4] It has diverse vocalizations, which have been intensely studied since the 1970s, particularly by Paul Handford and Stephen C. Lougheed (UWO), Fernando Nottebohm (Rockefeller University) and Pablo Luis Tubaro (UBA).

Local names for this bird include the Portuguese tico-tico, the Spanish copetón ("tufted") in Colombia, as well as chingolo and chincol, comemaíz "corn eater" in Costa Rica, and Cigua de Constanza in the Dominican Republic.

[5] Young birds have a duller, indistinct head pattern, with brown stripes and a buff ground colour.

The largest of the tepui subspecies, Z. c. perezchincillae, has grey underparts, and the rufous collar extends as a black band of freckles across the breast.

It can be seen in virtually any open or semi-open habitat, including cultivations, gardens, parks, grasslands, and scrubby second growth or cerrado.

By contrast, at 2,000 m (6,600 ft) ASL in the Andes of Pichincha Province (Ecuador), eggs were being incubated in December, and nest-building activity was recorded in March and April, suggesting extended breeding throughout the wet season.

Brood parasitism, e.g. by the shiny cowbird (Molothrus bonariensis), may occur, and breeding failure due to predation is very frequent during the incubation period.

Strategies used to acclimate to changing seasonal temperatures include limiting the amount of evaporative water loss (EWL) and increasing metabolic rate.

[18] This upregulation and expression are plastic, as found when high- and low-altitude birds were brought to a low elevation and no longer showed differences in gene transcription.

Other research has shown that rufous-collared sparrows from lower and higher elevations had similar metabolic responses to low oxygen conditions, but that high-altitude birds were more cold tolerant.

The male's song, given from a low perch, typically includes slurred whistles with or without a final trill, tee-teeooo, e’e’e’e’e, or teeooo, teeeee.

In some areas (in arid parts of northwest Argentina, eastern Patagonia, and certain sites in Costa Rica) there is often or always no terminal trill and the song comprises whistles only.

So far as is known (based on the Ph.D. thesis studies of Tubaro[23]), the development of vocal abilities seems to be very similar to the white-crowned sparrow (Z. leucophrys).

The geographic variation in the song of this species became apparent over 30 years ago with F. Nottebohm's study[20] in subtropical and temperate Argentina.

He interpreted his findings largely in the context established a few years before in the white-crowned sparrow,[24] that is, he suggested that these dialects perhaps serve to enhance the genetic integrity of local populations.

The first direct investigation of this possibility,[25] while providing no support for what came to be called the "genetic adaptation hypothesis" (GAH), which explains the vocal dialects of the brown-headed cowbird (Molothrus ater) well.

[26] [clarification needed] showed that the spatial organisation of song variation was very closely associated with the distribution of distinct habitat types.

Moreover, the structural characteristics of the dialect variable (trill interval) showed variation largely consistent with the interspecific acoustic patterns described by E.S.

They showed that the ecological ordering of dialect variation[22][28][29][30] over a huge geographical space (1,200 km × 350 km or 750 mi × 220 mi) and across a dramatic sweep of structurally distinct habitats (puna scrub, grassland, desert scrub, thorn woodland, and drought-deciduous forest (see Figure) was largely consistent with the previously established picture.

The most recent work on this species confirms that the clear ecological segregation of acoustically rational vocal dialects in Argentina extends from 22ºS at the Bolivian border south to 42ºS in northern Patagonia.