| Popis: |
The clutches of many birds tend to hatch synchronously (Lack 1968) and may also hatch at night (pers. observ.). Thus, it is difficult to determine which young hatched from which egg, even with frequent nest visits (e.g., Fiala 1981). The ability to easily assign nestlings to specific eggs would aid in accumulating the large samples that are needed to elucidate the effects of different patterns of parental investment. Precise relationships of egg-laying order, egg size, hatching order and clutch size to hatchling quality (e.g., probability of fledging) could be determined. In this paper we present a method of dyeing embryos while still in the egg, thus permitting such questions to be examined directly. |
