A recent story from Mexico may provide some clues. In 2006, a mysterious illness began to affect girls at a boarding school in Chalco, Mexico, near Mexico City. The school, which is run by Roman Catholic nuns, is one of 10 in Asia and Latin America operated by a charity called World Villages for Children in Asia.
There are also several marine mammals like Orca's (killer whales), harbor seals and sea lions that live in the Seattle area in the cold waters of Puget Sound and the Pacific Ocean and feed on the salmon and other fish. Douglas squirrels rely on the the evergreen trees that are native to the area.
Order Monotremata. This is a small and unique order of mammals placed by themselves in the subclass Prototheria. There are only 3 living species of monotremes â one species of duck-billed platypus and two species of echidna. Very little is known about them from the fossil record. What makes these mammals so unique is their egg-laying ability, a trait found in no other mammals.