Sexual/Female deception

Deception of plumage colours in Pied Flycatcher birds

This blog is on the topic of sexual mimicry and in particular for this species it is female mimicry. This is when a male mimics a female in order to deceive other males. They mimic their behavior, morphology or chemical signals. (Wikipedia, 2015)

During mating season the male Pied Flycatcher bird Ficedula hypoleuca is extremely aggressive towards other males with brightly coloured plumage. They are aggressive towards the males however they act sexually towards the less brightly coloured females. It has been found that these birds can also use deception when they intrude on a claimed area of the male bird. They use appearance deception and the male F.hypoleuca is deceived by another male with less brightly coloured plumage. The male acts sexually towards this male intruder(Slagsvold and Saetre, 1991).

There are a number of proposed causes for this deception. These include a delay in the sexual maturation, status signalling and spring molt constraints.

One reason for these delays of plumage colour could be to allow the younger bird to get a place in a previously occupied space in an older males territory. 

The molt hypothesis would be evolutionary not beneficial because this would prevent the younger birds from being able to mate for that year, therefore preventing the passing on of their genes.(Slagsvold and Saetre, 1991) 

The status signalling hypothesis suggests that the plumage colouration shows a female how useful the male is, in terms of reproductive quality. The plumage colour also could suggest the health of the genetics of the male. (Siitari, 2002)

Figure 1: Brown colour of young males or females (Wood, 2015)

Figure 2: Black and white colour of males / elder males. (Jonczyk, 2008)

References 

Jonczyk, P. (2008). [image] Available at: http://ibc.lynxeds.com/photo/european-pied-flycatcher-ficedula-hypoleuca/male [Accessed 8 May 2015].

Siitari, H. (2002). Individual color variation and male quality in pied flycatchers (Ficedula hypoleuca): a role of ultraviolet reflectance. Behavioral Ecology, 13(6), pp.737-741.

Slagsvold, T. and Saetre, G. (1991). Evolution of Plumage Color in Male Pied Flycatchers (Ficedula hypoleuca): Evidence for Female Mimicry. Evolution, 45(4), p.910.

Wikipedia, (2015). Sexual mimicry. [online] Available at: http://en.wikipedia.org/wiki/Sexual_mimicry [Accessed 8 May 2015].

Wood, J. (2015). [image] Available at: http://www.pbase.com/wildbirdimages/image/128748337 [Accessed 8 May 2015].