We thought we were the only species to enjoy intimate interactions, but as Jason G Goldman discovers, a few curious couplings in nature have changed our view. Sex, we are told, is pleasurable. That's because most scientific accounts of sexual behaviour rest upon evolutionary explanations rather than the more immediately relevant mental and emotional experiences.
Ovis canadensis is found in the Rocky Mountains from southern Canada to Colorado, and as a desert subspecies O. Festa-Bianchet, Ovis canadensis canadensis inhabits alpine meadows, grassy mountain slopes and foothill country in proximity to rugged, rocky cliffs and bluffs.
Domestic rams were used as an animal model for this research because they display distinct, natural variations in sexual attraction, making them valuable in studying the biological basis for sexual partner preference. Previous studies documented that approximately 6 percent to 8 percent of domestic rams court and mate with other rams exclusively. Sheep selected for this research were chosen after their sexual partner preference and mating habits were studied for two years. A total of 27 sheep were studied: nine rams that preferred to mate with males, eight rams that preferred to mate with females, and ten ewes.
Domestic sheep live worldwide in association with humans. The first domesticated sheep resided mainly in the Middle East and Central Asia but since then have been introduced everywhere. Domestic sheep are extremly versitile and exist in a wide variety of habitats worldwide ranging from temperate mountain forests to desert conditions.
As with other mammalsdomestic sheep reproduction occurs sexually. Their reproductive strategy is very similar to other domestic herd animals. A flock of sheep is generally mated by a single ram, which has either been chosen by a farmer or has established dominance through physical contest with other rams in feral populations.
In their natural state, sheep are seasonal breeders; offspring are born at the time most favorable for their survival. In some domestic sheep, the breeding season has been altered both naturally and through the use of hormones. Age of Puberty. Ewes typically reach puberty at 5 to 12 months, depending on breed, nutrition, and date of birth.
By Helen Phillips. A study of gay sheep appears to confirm the controversial suggestion that there is a biological basis for sexual preference. The work shows that rams that prefer male sexual partners had small but distinct differences in a part of the brain called the hypothalamus, when compared with rams that preferred to mate with ewes.
A study published in the February issue of the journal Endocrinology demonstrates that not only are certain groups of cells different between genders in a part of the sheep brain controlling sexual behavior, but brain anatomy and hormone production may determine whether adult rams prefer other rams over ewes. Roselli, Ph. The results lend credence to previous studies in humans that described anatomical differences between the brains of heterosexual men and homosexual men, as well as sexually unique versions of the same cluster of brain cells in males and females.