Integrated 10

Either subject of the reading or the lecture is pointing to the reasons of declination of sea otter population which is a tiny mammal lives in the western coast of North America from California to Alaska. In this case, the article alleges the most probable theory for this issue is environmental pollution. However, the lecture casts a shadow of doubt on the proposed idea of the article in which it has been disapproved by the same sources.

First and for most, the lecture brings up the view that pollution theory is weakened because nobody could not find any dead atters washing off the beaches. If industrial chemical pollution had caused the reduction of the size of otters, there would be a large number of dead otters along the Alaskan coast. As a result, otters were killed by their predators and the predation theory could be more indisputable reason than pollution. While this directly repudiates the article which declares industrial chemical materials were fundamental reason for diminishing the number of otters.

Based on the passage, the second critical factor is environmental pollution is unavoidable clarification due to the fact it have had impact on the population of other sea mammals and made their numbers go down. On the contrary, the lecture challenges the claim by stating that whales were hunted by humans, so the orca forced to modify their diet and start catching and eating other small mammals such as otters, seals and sea lions.

Finally, the lecture contends that uneven pattern is better explanation than pollution and predation for otter reduction. A suitable location for otters depends on accessing to orcas. If in one place orcas are accessible, the number of otters would decrease. Also the shallow and rocky sites are desirable for living otters since the orcas could not live there. Eventually, the lecture asserts the uneven pattern can confirm the predation theory for this problem. This completely refutes what the reading indicates natural elements have produced various levels of pollutants along different coasts and it could correlate with reduction of otters at some Alaskan sites.