A type of small snail is very widespread in Japan, and colonies of the snails that are genetically similar have been found very far apart. Scientists wondered how the snails could travel such long distances. A recent study¹ provides the answer. Biologist Shinichiro Wada fed 174 live snails to birds and found that 26 of the snails were excreted live out the other end. The snails apparently are able to seal their shells shut to keep the digestive fluids from getting in.

(a) What is the best estimate for the proportion of all snails of this type to live after being eaten by a bird? Round your answer to three decimal places. Best estimate = ___

b) Figure 1 shows a bootstrap distribution based on this sample.

Left Tail Two-Tail Right Tail samples = 1000 100 mean = 0.150 std. error = 0.027 80 .......... 60 40 20 : 0 : : 0.06 0.08 0.10 0.12 0.14 0. 16 0. 18 0.20 0.22 0.24 0.15