HealthWomen's pelvises are shrinking – how is that changing childbirth? Over the past 150 years, the rise in Caesarean sections and changes in diet could have led to smaller pelvises among women – which may make vaginal birth more difficult but could also reduce common conditions associated with childbirth ¿ìè¶ÌÊÓÆµ
LifeGiant ground sloths evolved three different times for the same reason An analysis of the sloth family tree suggests three different groups of the animals evolved to gigantic sizes in response to cold and dry conditions ¿ìè¶ÌÊÓÆµ