Talking of eggs laid long ago, when are Common Gull and Mew Gull going to be split? The current comment on the
IOC page:
is long out of date, as nominate
canus has been analysed; the break is between
brachyrhynchus and the rest (e.g. Sternkopf 2011, Adriaens & Gibbins 2016).
Also with the recent split of Cassia Crossbill, the crossbills need further splitting; American Red Crossbills (
Loxia [
curvirostra]
minor et al.) are more closely related to Cassia Crossbill than they are to Eurasian Common Crossbills (
Loxia curvirostra sensu stricto, including other Eurasian subspp.), while conversely, European Common Crossbills are more closely related to Parrot Crossbill, than they are to American Red Crossbills.