INTRACLUTCH EGG-SIZE VARIATION IN MAGELLANIC PENGUINS

摘要: Abstract We investigated patterns and consequences of intraclutch egg-size variation in Magellanic Penguins (Spheniscus magellanicus). First-laid eggs were significantly larger than second-laid eggs, although the mean difference represented only 2% an average egg's volume. The degree was similar among years females different ages. Intraclutch did not affect differences chick hatching weights or fledging success. found no selective advantage for laying sizes. Because both have equal probability being lost, chance favors provisioning eggs. Egg volume explained 35% weight but determine Laying order, year, female age better predictors success egg size. Factors such as parental quality, oceanographic conditions, fights, predation are more important determining survival ...