Animal sexual behaviour however, is proving to be false as, "most hormones don’t influence behaviour directly. Rather, they affect thinking and emotions in variable ways (Azar, 40)." There is much more involved in sexual behaviour in the mammalian animal than oxytocin and vasopressin can explain. It is often assumed that animals do not have sex for pleasure, or alternatively that humans, pigs, bonoboes (and perhaps dolphins and one or two more species of primates) are the only species that do. This is sometimes stated as "animals mate only for reproduction". This view is considered a misconception by some scholars. Jonathan Balcombe argues that
Human sex ratio girls. He concluded by calculation of a "p"-value that the excess was a real, but unexplained, effect. Countries: Human sex ratio In anthropology and demography, the human sex ratio is the ratio of males to females in a population. More data is available for humans than for any other species, and the human sex ratio is more studied than that of any other species, but interpreting these statistics can be difficult. Like most sexual species, the sex ratio in humans is approximately 1:1. Due to higher female fetal mortality, the sex ratio at birth worldwide is commonly thought to be