Quote Originally Posted by Badgemash View Post
phenotype - noun
BIOLOGY1.
the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.

Blood proteins and immune responses do not fell under the definition of phenotype, you cannot see them. You are referring to genotype.
ob·ser·va·tion (bzr-vshn)n.1. a. The act or faculty of observing.
b. The fact of being observed.

2. a. The act of noting and recording something, such as a phenomenon, with instruments.
b. The result or record of such notation: a meteorological observation.

3. A comment or remark. See Synonyms at comment.
4. An inference or a judgment that is acquired from or based on observing.


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anything that can be measured with any device or instrument is observable. that includes not just your eyes, but also your ears, sense of smell, your infrared temp gun, the hubble space telescope, the results from gas chomatography or X-ray crystallography and a multitude of other things. we have no human eyes on mars, yet we observe a lot. thats how it is in science, and a scientific definition of "phenotype" would obviously utilize the scientific definition of "observation". no one has ever seen an atom, or a neutrino, or a supermassive black hole, but we can observe them. thats good enough, our eyes are quite limited anyway.