div class=ts-pagebutton class=gotoPage data-page=1Page 1button div class=ts-imageimg data-url=are-sons-worth-more-than-daughtershtmlpage=1 data-page=1 class=ts-thumb lazyload alt=Page 1: Are sons worth more than daughters loading=lazy src=data:imagegifbase64iVBORw0KGgoAAAANSUhEUgAAAAIAAAACCAQAAADYv8WvAAAAD0lEQVR42mP8X8AwAgiABKBAv+vAXklAAAAAElFTkSuQmCC data-src=https:reader036vdocumentssitereader036viewer20220731075750686a1a28ab0f07b010afhtml5thumbnails1jpg width=140 height=200 divp© Nature Publishing Group1983p div class=annotation div class=annotationTitleanudiv div class=annotationContentsIMAGE UNAVAILABLE FOR COPYRIGHT REASONSdiv divdiv