Recently ApexCo has begun drilling off the coast of Mycondia. In this time, the number of animals that end up on the beach, coated in oil and other industrial by-products, has increased dramatically. Nonetheless, no Peterson's loggerhead turtles, a tortoise common in the waters off the coast of Mycondia, have washed upon shore. ApexCo's public relations claim that while some of the by-products are clearly harmful to aquatic life, the lack of Peterson's loggerhead turtles that are washed ashore suggest that not all the aquatic life there is adversely affected.
Which of the following, if true, casts the most doubt on the argument employed by ApexCo's public relations firm?