One Tailed Hypothesis

Correct. A one tailed hypothesis specifies a directional relationship between groups. Here we are saying that we expect children in Samoa to be further from their mothers than children in Belize. We not only state that there will be differences between the groups but we specify in which direction the differences will exist. Anytime we expect a relationship to be directional (i.e. to go one specific way) we are using a one-tailed hypothesis. This is the opposite of a two-tailed hypothesis. A two tailed hypothesis would predict that there was a difference between groups, but, would make no reference to the direction of the effect.
Now want do you want to do???