Smaller testicles linked to caring fathers
by TIA GHOSH
Men with larger testicles tend to be less involved fathers than those with smaller testes, a new study suggests.
The findings, detailed today (September 9) in the journal Proceedings of the National Academy of Sciences, are correlational, so they can’t say exactly why the trend exists but only that there is a link.
But men who produce more sperm have bigger testes, and sperm production is extremely energy intensive for the body, so it may be that fathers “face a trade-off between investing energy in parenting and investing energy in mating effort,” said study co-author James Rilling, an anthropologist at Emory University in Atlanta.
Scientific American for more
Environmental changes contributed to Mediterranean cultural crisis
EARTH
About 3,200 years ago, urban cultures thrived in the Eastern Mediterranean until invasions in coastal and inland areas, compounded by agricultural decline, created a regional crisis. “When the dust settled,” says Harvey Weiss, an archaeologist at Yale University, “entirely new ethnic groups and polities and ideologies [were] emergent in west Asia and the eastern Mediterranean.” Scientists have long puzzled over the cause of this period of social and agricultural instability, known as the Late Bronze Age Crisis. Now, new research suggests that environmental changes — especially a prolonged drought — contributed to the unrest.
David Kaniewski, associate professor in the Biology and Geosciences Department at the Université Paul Sabatier-Toulouse III in France, Joel Guiot, research director at the Centre National de la Recherche Scientifique in France, and their colleagues set out to place the archaeological record from this time period in an environmental context. This study is an attempt to understand “the environmental conditions when everything started to decline [and] to finally collapse,” Kaniewski says.
Earth for more