The problem with science is that it is conducted by individuals who tend to be Left-Hemisphere dominant, and this means they think in linear terms.
As a consequence they miss some really obvious things that those who have use of both hemispheres are able to "see".
The assumptions of the Left-Hemisphere individual, being linear, would not imagine that a "smart" monkey could live on other islands as well. The assumption that what one is observing is the only occurrence of that being observed is linear.
But what really is missing in science and the Left-Hemisphere dominant individual is Knowledge that the brain is the most limited faculty Man has available for seeking knowledge. Intuition is far more useful, truthful, accurate, and is not subject to the subtle influence of ones MIND as it interferes with ones search for Truth.
To worship one-third of Man [while denying two-thirds of Man] is sad in many ways.