How does sound reception differ between humans and dolphins?

The dolphins and the humans occupy two different environments. The medium of sound propagation in these environments diffrer, water and air. The sound travels faster and further in water than air. Dolphin has a tiny ear-like opening above its eye. This tiny pit or ear-like opening helps in the hearing sense. In humans, ears are visible on the sides of the head. In dolphin, the sound enters the pit and is perceived by the jaw bone structure. In humans, the tiny hair-like structures in the ear and the ear drum helps in perceiving the sound. These are the main structural differences present in the two organisms.  

metamorphism is the change of minerals or geologic texture (distinct arrangement of minerals) in pre-existing rocks (protoliths), without the protolith melting into liquid magma (a solid-state change). the change occurs primarily due to heat, pressure, and the introduction of chemically active fluids. i hoped i !