Avian clutch size of increasing clutch size with increasing latitude. The proximate and ultimate causes for this pattern have been a subject of intense debate involving the ideas of group and individual selection. David Lack observed a direct relationship between latitude and avian clutch size. Birds near the equator laid approximately half as many eggs as those that resided in northern temperate habitats. He observed an increasing clutch-size from the equator towards the poles (something he referred to as the “latitude trend”) for many passerine (perching) birds, near-passerine (tree-dwelling) birds and in various other groups: Strigiformes, Falconiformes, Ciconiiformes, Laridae, Ralliformes, Galliformes, Podicipedifomes, and
Which Side Are You On? "Coal Mining Women". The song is referred to by Bob Dylan in the song "Desolation Row". It was also the inspiration for the title of Alessandro Portelli's 2011 book on Harlan County's coal mining community. Which Side Are You On? "Which Side Are You On?" is a song written in 1931 by Florence Reece, the wife of Sam Reece, a union organizer for the United Mine Workers in Harlan County, Kentucky. In 1931, the miners and the mine owners in southeastern Kentucky were locked in a bitter and violent struggle called the Harlan County War. In an attempt to intimidate