Complex sentence: The shortness of its legs is its most defining characteristic, and imparts a waddling gait to the chicken; adult birds are less 5 centimetres (2 inches) off the ground.
Split into simpler sentences: The shortness of its legs is its most defining characteristic, and imparts a waddling gait to the chicken. Having short legs; adult birds are less 5 centimetres (2 inches) off the ground.