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Externally, we (humans) look symmetrical. However, internal organs don't show the same patterns of symmetry (heart being on the left side while the liver is on the right side, etc.). It is a bit counter-intuitive to me that the exterior of our body seems to be mainly symmetrical while the interior is asymmetrical.
What is the advantage of having bilateral symmetry in our body?
Why don't all of our organs exhibit bilateral symmetry?