Zhongjianornis an enlarged, keeled breastbone in more advanced birds. However, later analysis of the anatomy of "Z. yangi" cast doubt on this interpretation of the bird as very primitive. Research published in 2012 found that some of the apparently primitive features were due to poor preservation of the bones, and that "Zhongjianornis" is more similar in anatomy to primitive euornitheans like "Chaoyangia" and "Schizooura". A phylogenetic analysis showed that a very primitive position in the bird family tree for "Z. yangi" is unlikely given current evidence. Zhongjianornis Zhongjianornis is a genus of beaked, pigeon-sized birds from the early Cretaceous period of
Society for the Scientific Study of Sexuality Society for the Scientific Study of Sexuality The Society for the Scientific Study of Sexuality (SSSS, or "quad-S"), formed in 1957, is a non-profit, international professional membership organization, based in the United States, that says it is "the oldest professional society dedicated to the advancement of knowledge about sexuality." It reports to have more than 1,000 members and has a quarterly newsletter, "Sexual Science". It produces two other publications: According to its website, SSSS was established in 1957 by psychologist Albert Ellis to encourage the rigorous, systematic study of sexuality. In 1980, organizer Robert Francoeur invited Philadelphia biologist Timothy Perper