Editing Sexual selection (section)

=== Honest signalling ===

{{Further|Signalling theory}}

The [[handicap principle]] of [[Amotz Zahavi]], [[Russell Lande]] and [[W. D. Hamilton]], holds that the male's survival until and through the age of reproduction with seemingly maladaptive traits is taken by the female as [[Signalling theory|a signal]] of his overall fitness. Such handicaps might prove he is either free of or resistant to [[disease]], or that he possesses more speed or a greater physical strength that is used to combat the troubles brought on by the exaggerated trait.<ref name="Zahavi 1975 pp. 205–214">{{cite journal |last=Zahavi |first=Amotz |author-link=Amotz Zahavi |title=Mate selection—A selection for a handicap |journal=Journal of Theoretical Biology |volume=53 |issue=1 |year=1975 |doi=10.1016/0022-5193(75)90111-3 |pages=205–214 |pmid=1195756 |bibcode=1975JThBi..53..205Z }}</ref><ref name="Zahavi 1977 pp. 603–605">{{cite journal |last=Zahavi |first=Amotz |author-link=Amotz Zahavi |title=The cost of honesty |journal=Journal of Theoretical Biology |volume=67 |issue=3 |year=1977 |issn=0022-5193 |doi=10.1016/0022-5193(77)90061-3 |pages=603–605|pmid=904334 |bibcode=1977JThBi..67..603Z }}</ref><ref name="Zahavi Zahavi 1997">{{cite book |last1=Zahavi |first1=Amotz |author1-link=Amotz Zahavi |last2=Zahavi |first2=Avishag |title=The handicap principle: a missing piece of Darwin's puzzle |publisher=Oxford University Press |location=New York |year=1997 |isbn=978-0-19-510035-8 |oclc=35360821 |url=http://eprints.soton.ac.uk/261475/1/10.1.1.40.3266.pdf}}</ref> Zahavi's work spurred a re-examination of the field and several new theories. In 1984, Hamilton and [[Marlene Zuk]] introduced the "Bright Male" hypothesis, suggesting that male elaborations might serve as a marker of health, by exaggerating the effects of disease and deficiency.<ref name="HamiltonZuk1982">{{cite journal |last1=Hamilton |first1=W. D. |author1-link=W. D. Hamilton |last2=Zuk |first2=M. |author2-link=Marlene Zuk |title=Heritable true fitness and bright birds: a role for parasites? |journal=Science |volume=218 |issue=4570 |year=1982 |pages=384–387 |doi=10.1126/science.7123238 |pmid=7123238 |bibcode=1982Sci...218..384H }}</ref>