The picture below shoes the limbs of four different species. The four species illustrated most likely have similar limb structures because they all adapted to the same environmental conditions
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use their limbs for the same function
occupy the same level of the food pyramid
share a common ancestor

Because the earth is not round ,but it may seem round when viewed from ,our planet but true some points earth is not round was an oblate spheroid -a square that it squashed as globe however is not even a perfect oblate spheroid.in fact isaac newton's first proposed that earth was not perfectly round but it was an oblate spheroid instead.that mean a square that is squashed as its poles and swollen at the