In addition to critically examining the evidence brought forward by ethological attachment theorists we should investigate if attachment can be explained through other mechanisms. Maybe it is not just the caregiving style that affects attachment security. Maybe it is not the early experience or environment that matters at all. We need to look at the possibility that attachment security is influenced biologically in correlation with temperament. If this were to be found true, the basis of attachment theory could be challenged. The question is this: Can attachment theory withstand the challenge?