DEMOGRAPHY AND SEX RATIO IN SOCIAL SPIDERS

Demography and Sex Ratio in Social Spiders.

Spiders that live in large cooperative societies are scattered among several taxonomic groups. All quasisocial species appear to have female-biased sex ratios, while congeneric species with less advanced forms of sociality have 1:1 sex ratios. I present two sex-ratio models that examine the interaction between the genetic structure of populations and two aspects of colony demography-the changes...

Social spiders

References 1. Buss, L.W. (1987). The Evolution of Individuality (Princeton, New Jersey: Princeton University Press). 2. Bonner, J.T. (1967). The Cellular Slime Molds, Second Edition (Princeton, New Jersey: Princeton University Press). 3. Buss, L.W. (1982). Somatic cell parasitism and the evolution of somatic tissue compatibility. Proc. Natl. Acad. Sci. USA 79, 5337–5341. 4. Kessin, R.H. (2001)....

Evolution: Sex and Cannibalism in Redback Spiders

Female redback spiders cannibalise mating males. New research has shown they have evolved two separate sperm storage organs, allowing them to make post-copulatory paternity choices. Counter-adaptation by males, to maximise paternity after cannibalism, has led to the evolution of an abdominal constricting mechanism, which enhances short-term survival and mating success after attack by the female...

Social Demography

Demography and the social contract.

As the most demographically complex nation in the world, the United States faces ever more formidable challenges to fulfill its commitment to the democratic values of equity and inclusion as the foreign-born share of the population increases. Immigration, the major source of the contemporary diversification of the population, provides several lessons about how to prepare for that future within ...