Egg investment strategies adopted by a desertic passerine, the Saxaul Sparrow (Passer ammodendri)

Background As one of the reproductive strategies adopted by bird species, variation in investment in egg production and its influencing factors are important and well-studied subjects. Intraclutch changes in egg size associated with laying order may reflect a strategy of “brood survival” or “brood reduction” adopted by female birds in different situations. Methods We conducted field studies on the breeding parameters of the Saxaul Sparrow (...