Bonus 1 due W 228 I hope she

Bonus 1 due W 2/28 I hope she likes my feathers because I am tired of dragging them around everywhere.

Am I the only one? Am I better off helping with these kids or should I mate with someone else? Is this the best I can do? Maybe I can find someone with better genes or more genetic diversity.

1 Which is male? 2

1 Which is male? 2

Female grizzly bears cannot reproduce while lactating. Therefore they can only reproduce every once every 3 years…

…this leads to competition between males

Sexual Dimporphism: differences between males and females

Average height/weight by sex in U. S.

Ratio of Weight Male/Female M/F

Bonobos

Primates have different reproductive stratagies

Ratio of Weight Male/Female M/F

Testicle size (oz) per body weight (lbs) Testes Compared to Overall Weight

Pipefish: related to seahorses

Pregnant Male: Males care for developing eggs

Males care for developing eggs

The Measurement of Sexual Selection Using Bateman’s Principles: An Experimental Test in the Sex-Role-Reversed Pipefish Syngnathus typhle (2005) Integrative and Comparative Biology, 45: 874– 884 Adam G. Jones, Gunilla Rosenqvist, Anders Berglund, and John C. Avise

frequency Jones et al. Fig. 1 number of mates

frequency Jones et al. Fig. 1 number of mates

frequency Jones et al. Fig. 1 number of mates

The sex ratio affects who will successfully reproduce. Pipefish females are more affected. Jones et al. Fig. 1

number of individuals Jones et al. Fig. 4 body length (mm)

number of individuals Jones et al. Fig. 4 body length (mm)

medium sized female pipefish are most successful at reproducing while size is less critical for male pipefish Jones et al. Fig. 4

Different reproductive strategies lead to differences in sexual dimorphism.