Latitudinal Trends in the Metabolic Adjustments of the House Sparrow

Abstract

Between latitudes 9° and 59° in North America, the House Sparrow, Passer domesticus, shows progressive increases northward in energy expenditures for temperature regulation, existence metabolism, reproduction, daily energy budget, permanent residency, and mobilizable energy. Energy requirements are greater in the winter than in the summer for temperature regulation, existence metabolism, daily energy budget, and mobilizable energy. Seasonal acclimatization to winter temperatures brings lower rates at equivalent temperatures in existence metabolism. However, latitudinal adaptation at colder northern latitudes brings higher rates at equivalent temperatures in existence metabolism. The number of broods produced per year is inversely proportional to the energy cost per brood, and the energy expended by the species for reproduction is approximately the same at all localities. The reduction in work capacity at high ambient temperatures increases southward, but is greater in desert climates with large daily and seasonal fluctuations in temperature than in the tropics with their uniform climates. The species may be limited in dispersal into desert regions by daily maximum temperatures that approach or surpass its upper limit of tolerance, but is capable of dispersing through the Central American tropics into South America. The species is limited northward by low temperatures at which it is unable to mobilize sufficient energy for existence and/or reproduction except where it makes use of artificial man-made shelters and food supplies. These variations and adjustments noted between geographic populations of the House Sparrow probably apply to bird species generally.

Space invaders: House Sparrow densities along three urban-agricultural landscapes

“…Thus, depending on specific habitats and scenarios, House Sparrow numbers can resemble those of both urban exploiters/dwellers (Blair 1996, Fischer et al 2015 and urban adapters/users (Blair 1996, Fischer et al 2015, varying between cities located outside of its native range and even between urbanagricultural land classes within those cities. This agrees with a number of other studies that have shown that sparrow numbers can vary in both their native and nonnative distribution despite their reputation for high adaptability (Johnston and Selander 1964, Johnston and Selander 1973, Kendeigh 1976, Martin et al 2004) and exploitation of urban-and agriculture-related resources (Blair 1996, Fischer et al 2015.…”

Latitudinal variation in parental energy expenditure during brood rearing in the great tit

“…The general pattern of variation in energy expenditure with latitude is in agreement with the relationship of clutch size with latitude found in the great tit (Sanz 1998) and contrasts with the generalisation that the parental work load in breeding animals should increase linearly with latitude (Kendeigh 1976;Bryant et al 1984). This study points more in the direction of the existence of distributional limits that may reflect other costraints on conditions for reproduction such that larger parental effort cannot be selected for (Slagsvold 1981;Sanz 1998).…”

Investment in immune defense is linked to pace of life in house sparrows

“…Nevertheless, the extensive variation seen in many physiological and life history characteristics of North American house sparrows (Kendeigh 1976;Summers-Smith et al 1988) strongly suggests that immunological differences detected in this study are partly adaptive and perhaps genetic (Martin et al 2004). Moreover, because the immune system is arguably one of the most complex phenomena in biology, studies like this one can provide useful background for future, more controlled work in understanding the forces that determine the architecture of species' immune systems.…”

“…Although house sparrows are not native to the western hemisphere, populations exhibit many of the latitudinal life history clines of indigenous species, including a decrease in clutch size (Summers-Smith 1988), an increase in the length of the breeding season (Summers-Smith 1988), and a decrease in rate of energy turnover (Kendeigh and Blem 1974;Kendeigh 1976) towards the equator. Birds in this study were from a North-temperate site (Princeton, New Jersey, USA: 40°21¢N, 74°40¢W), and a Neotropical site (Colon, Panama: 9°1¢N, 80°1¢W; see Martin et al 2004 for details).…”