n Christian countries the “love mood” is higher around Christmas time and so are online searches related to sex, whereas in Muslim countries a similar behaviour happens around the religious festivities of Eid-al-Fitr and Eid-al-Adha. Scientists at the Instituto Gulbenkian de Ciencia (IGC, Portugal) and Indiana University (IU, USA) showed that there is a specific mood associated with religious celebrations, and that this “loving mood” can influence human reproductive behaviour. The research team led by Joana Goncalves-Sa and Luis Rocha used worldwide data from Twitter and Google Trends to find that culture, and not only biology, drives human reproductive cycles. This study is published in the open access journal Scientific Reports . In Northern hemisphere Western countries, more babies are born in September than in other months of the year. This means that more babies are conceived in December and that human reproduction displays a cyclical pattern. Until now, it wa...