He also suggested the idea of replacing the original clutch with another clutch but with a single foreign egg and suggested based on his own results that either the foreign eggs would be discarded or that the birds would abandon the nest.
Tamén suxiriu a idea de substituír a niñada orixinal por outra, pero cun só ovo estraño e afirmou, baseándose nos seus propios resultados, que os ovos estraños eran descartados, ou que as aves abandonaban o niño.