Odd Couples: Extraordinary Differences between the Sexes in the Animal Kingdom
Daphne J. Fairbairn
Format: PDF / Kindle (mobi) / ePub
While we joke that men are from Mars and women are from Venus, our gender differences can't compare to those of many other animals. For instance, the male garden spider spontaneously dies after mating with a female more than fifty times his size. And male blanket octopuses employ a copulatory arm longer than their own bodies to mate with females that outweigh them by four orders of magnitude. Why do these gender gulfs exist?
Introducing readers to important discoveries in animal behavior and evolution, Odd Couples explores some of the most extraordinary sexual differences in the animal world. Daphne Fairbairn uncovers the unique and bizarre characteristics of these remarkable species and the special strategies they use to maximize reproductive success. Fairbairn also considers humans and explains that although we are keenly aware of our own sexual differences, they are unexceptional within the vast animal world.
Looking at some of the most amazing creatures on the planet, Odd Couples sheds astonishing light on what it means to be male or female in the animal kingdom.
rapidly change color and pattern. 47. Garm et al. (2007). 48. Endler (1992, 1993) and Gomez and Théry (2007). 49. The exceptions are the arthropod classes Pauropoda and Symphyla, the mollusk class Monoplacophora, and the poriferan class Calcarea. These are minor classes totaling fewer than 1,100 species. Chapter 12: Concluding Remarks 1. In primates sexual dimorphism is strongly associated with the intensity of sexual selection on males through both competition among males to monopolize
A. Gilad, K. Klass, and Y. L. Werner. 2009. Ontogenetically stable dimorphism in a lacertid lizard (Acanthodactylus boskianus) with tests of methodology and comments on life history. Biological Journal of the Linnean Society 97:275–88. Setchell, J. M., and A. F. Dixson. 2001. Changes in the secondary sexual adornments of male mandrills (Mandrillus sphinx) are associated with gain and loss of alpha status. Hormones and Behavior 39:177–84. Sharma, G. D., and L. J. Metz. 1976. Biology of the
when males have not yet completely sorted out their dominance relationships. Sometimes a group of females encounters a group of males, and the two sexes travel together creating temporary mixed-sex breeding flocks. If one male succeeds in enticing the females away from his confreres by judicious herding and display, a temporary harem-like grouping can occur with one breeding male and several females. As the season progresses displaying males tend to space themselves out in the lekking area,
distance, a barnacle cannot mate as either a male or a female unless it fertilizes itself, which barnacles seem very reluctant to do. The somewhat surprising solution to this dilemma has been for barnacles that tend to occur in low densities to abandon pure hermaphroditism in favor of having males that seek out and settle on larger, sessile females or hermaphrodites.4 The males are typically very small and have greatly simplified bodies. Once they have found a mate they stick to her for life and
mates, and males might count themselves lucky to find even one female. Parental care is rare and is almost always the female’s role, but in some species both parents care for the eggs or young, whereas in others this role is taken exclusively by males. The sexes tend to be most similar in species that release their eggs and sperm directly into the environment with no courtship or sexual contact between the spawning individuals. In many such species only gonadal tissue separates the sexes, and at