Explain why a 2-tailed paired samples test is appropriate for below:

A sample of 30 moth eating birds is selected. The animals are tested in an apparatus that consist of a two-chambered box. The birds are free to roam from one side of the box to the other through a doorway in the partition that separates the two chambers. In one chamber, there are two eye-spot patterns painted on the wall. The other side of the box has plain walls. One at a time, the researcher test each bird by placing it in the doorway between the chambers. Each bird is left in the apparatus for 60 minutes, and the amount of time spent in the plain chamber is recorded. To find out whether the birds show an avoidance of eye-spot pattern (i.e. spend less time in the chamber with the eye-spot patterns on the wall than in the chamber with no eye-spot patterns on the wall), you will need to examine whether the birds' looking behaviors differed from chance (i.e. the population mean) using the data set Stare aversion 1976.csv. The values in the "Proportion_eye_spot"" column present the proportion of time the birds spent in the chamber with the eye-spot patterns painted on the wall.