Because you cannot test it or observe it.
A scientific theory are created through the scientific method, in the scientific method you need to be able observe it and experiment.
Because their bodies tell them that they need more oxygen and so breathe faster, and try and get the oxygen their body requires and depends on.
I need more to answer the question
For a person with blood type A- (A negative), they can be transfused with either blood type A negative , or blood type O negative.
This is because any other blood type will immediately be rejected by their body.
A person with blood type A negative has got antibodies against any other blood type which has a rhesus positive factor as well as antibodies against any other blood type of a different group such as B and AB, even if they are rhesus negative.
Therefore because of the rhesus negative factor, a person with blood type A negative can only be transfused with rhesus negative .
Because squirrels don’t prey on other animals
