some characteristics are obvious like ability to roll tongue, type of thumb(straight, or curved), height, colour of fur, attached or detached earlobes, dimples, colour of eyes, hair, skin, colourful of flowers
some are less obvious like blood type, intelligence, quality of milk, quality of fruits,
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some genes are subject to change as height(change by diet), skin colour(suntanning), twins behave different(different environments)
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