Biology Reference
In-Depth Information
male manipulation. The result may be antagonistic coevolution between the sexes,
where females evolve resistance to male force or charm.
Further reading
The topics discussed in this chapter are a particularly vigorous field of research, and the
literature is vast. There are many excellent topics: Malte Andersson's (1994) topic
reviews
Sexual Selection
; Tim Birkhead and Anders Møller's (1998) edited volume
surveys
Sperm Competition
; and Göran Arnqvist and Locke Rowe's (2005) topic covers
Sexual Conflict
. Tim Birkhead's topic
Promiscuity
(2000) is an excellent popular scientific
account of all three topics. For shorter reviews, see Chapman
et al
. (2003) on Sexual
Conflict, Wedell
et al
. (2002) on Sperm Competition, Birkhead and Pizzari (2002) on
post-copulatory sexual selection, Andersson and Iwasa (1996) on Sexual Selection and
Clutton-Brock (2009a) on selection in males and females. Kokko
et al
. (2003) is a fine
review of models of mate choice; their key point is that direct and indirect (genetic)
benefits often go hand in hand. Bart Kempenaers (2007) reviews mate choice for
genetic quality.
Robert Brooks (2000) provides evidence for Fisher's model of sexual selection with
some clever experiments on guppies (see also Brooks & Couldridge, 1999). Pizzari and
Foster (2008) review the 'social life' of sperm, showing how sperm sometimes cooperate
as a team to enhance their fertilization success.
Trevor Price's topic
Speciation in Birds
(2008) discusses sexual selection and speciation
(Chapters 9-11) and Seddon
et al
. (2008) show that sexual selection has promoted
speciation in the antbirds of South America. Kokko and Jennions (2009) review the
links between parental investment and sexual selection.
Richard Prum (1997) shows how a phylogenetic analysis of male behaviour and
plumage in manakins (a tropical bird family) can test between alternative models of
sexual selection.
TOPICS FOR DISCUSSION
1.
Tim Clutton-Brock (2009a) suggests we should broaden the definition of sexual selection,
from one focusing on competition for mates to one focusing on competition for reproductive
opportunities, and we should emphasize the contrasting ways in which selection operates in
males versus females. Do you agree?
2.
How would you test the hypothesis that females should have greater control over sperm
choice in species where they have least control over mate choice?
3.
A recent experimental study by Bro-Jørgensen
et al
. (2007) suggests that variation in tail
length in barn swallows reflects natural selection, because the aerodynamically optimal tail
length varies significantly between males. How might this complicate the interpretation of
long tails as a sexually selected ornament?
4.
Suggest hypotheses for why male satin bowerbirds prefer blue objects while male spotted
bowerbirds prefer white and green objects. How would you test your hypotheses?
5.
Why in some species do males compete for females by force while in others they do so by
charm? Discuss the factors that might lead to one form of competition rather than the
other.
