Manatees and humans are both mammals. Because manatees and
humans are both mammals, we share the same type of cells such as blood cells, muscle cells, skin cells, brain cells, etc.
Most mammals have cavities in their "long bones" that make red blood cells and manatees do not.
Manatees' ribs and long bones are solid, and lacking marrow cavities. It is believed that the bones are solid to make them
heavier so the manatee can stay submerged in the water. (9)
Manatees
do however have adaptations in their cells that we humans do not. These adaptations help them live in the water. Because manatees
are aquatic mammals, they need to be able to hold their breathe longer so they can stay under water for longer periods of
time. To help them do so, their red blood cells have more hemoglobin and their muscle cells have more myoglobin. Together,
these adaptations in their cells help them hold more oxygen allowing them stay submerged in the water for longer periods of
time. (10)
