Mating among these gastropods is charged with romantic tension; two males and two females are caught up in every embrace.
Last year Charles Murray, a libertarian columnist and pundit, warned in "Coming Apart: The State of White America, 1960-2010" that mating among people of similar means is increasing the divide between a motivated elite and a listless underclass.
Intermarriages exhibit positive assortative mating among spouses natives and immigrants with similar level characteristics tend to intermarry.
Although most studies examined reported an increase in assortative mating among individuals with affective disorders, the degree of assortative mating reported varied widely.
The United Kingdom is closer to blackcap breeding grounds in central Europe than is Spain, so the northwest-migrating birds return home 10 days earlier and start mating among themselves.
In a classical breeding fashion, on the principle of recurrent mass selection and progeny testing, the genetic improvement of population through gene pool exploitation using restricted mating among selected progenies of chemotypically superior plant and high yielding genotype (variety 'CIM Arogya') was developed.
Darwin himself did not think natural selection would by itself generate racial distinctions, since the physical traits associated with racial differences did not seem sufficiently beneficial to favor their retention; he did, however, leave open a role for sexual selection in the creation of races, through repeated mating among individuals with similar traits (Bernasconi and Lott 2000, 77 78).
Mating among rodents can vary from monogamy, to polygyny, to promiscuity.
Our choice of birth function also implicitly assumes random mating among healthy and parasitized individuals.
We used individual based simulations of a finite and homogenous population with random mating among sexually reproducing individuals.
Rates of hybridization (mating) among the populations/genotypes are assumed to be exactly proportional to the relative population sizes of co-emerging individuals; e.g., no mate choice occurs.
