Editing Common cuckoo (section)

==Mimicry in adults==
[[File:European Cuckoo Mimics Sparrowhawk.jpg|thumb|left|Cuckoo adult (top) mimics sparrowhawk, giving females time to lay eggs parasitically|alt=Photo of sparrowhawk and cuckoo, looking similar]]
The barred underparts of the common cuckoo resemble those of the [[Eurasian sparrowhawk]], a predator of adult birds. A study comparing the responses of Eurasian reed warblers, a host of cuckoo chicks, to manipulated taxidermy model cuckoos and sparrowhawks found that reed warblers were more aggressive to cuckoos with obscured underparts, suggesting that the resemblance to sparrowhawks is likely to help the cuckoo access the nests of potential hosts.<ref name=Welbergen2011>{{cite journal |last1=Welbergen |first1=J. |last2=Davies |first2=N. B. |year=2011 |title=A parasite in wolf's clothing: hawk mimicry reduces mobbing of cuckoos by hosts |journal=[[Behavioral Ecology (journal)|Behavioral Ecology]] |volume=22 |issue=3 |pages=574–579 |doi=10.1093/beheco/arr008|doi-access=free }}</ref> Other small birds, [[great tit]]s and [[blue tit]]s, showed alarm and avoided attending feeders on seeing either (mounted) sparrowhawks or cuckoos; this implies that the cuckoo's hawklike appearance functions as protective mimicry, whether to reduce attacks by hawks or to make brood parasitism easier.<ref name="Davies and Welbergen 2008">{{cite journal |last1=Davies |first1=N. B. |last2=Welbergen |first2=J. A. |title=Cuckoo–hawk mimicry? An experimental test |journal=Proceedings of the Royal Society B: Biological Sciences |date=2008 | volume=275 |issue=1644 |pages=1811–1816 |doi=10.1098/rspb.2008.0331 |pmid=18467298 |pmc=2587796}}</ref>

Hosts attack cuckoos more when they see neighbors [[Mobbing (animal behavior)|mobbing]] cuckoos.<ref name="ccevo2012">{{cite journal |last1=Thorogood |first1=R. |last2=Davies |first2=N. B. |year=2012 |title=Cuckoos combat socially transmitted defenses of reed warbler hosts with a plumage polymorphism |journal=[[Science (journal)|Science]] |volume=337 |issue= 6094|pages=578–580 |doi=10.1126/science.1220759 |pmid=22859487|bibcode=2012Sci...337..578T |citeseerx=10.1.1.1030.5702 |s2cid=8898295 }}</ref> The existence of the two plumage morphs in females may be due to frequency-dependent selection if this learning applies only to the morph that hosts see neighbors mob. In an experiment with dummy cuckoos of each morph and a sparrowhawk, reed warblers were more likely to attack both cuckoo morphs than the sparrowhawk, and even more likely to mob a certain cuckoo morph when they saw neighbors mobbing that morph, decreasing the reproductive success of that morph and selecting for the less common morph.<ref name="ccevo2012"/>