Imagine an underwater world where cows and turtles gently graze on lush, grassy, tree-lined meadows, surfacing every few minutes to take a breath before they slowly descend back to the nutrient-rich fields. Science fiction? Not for a manatee. Manatees, or sea cows, are gentle giants who live in peaceful coastal and inland waterways. Their serene world is a far cry from the fast-paced life of the open ocean.
Another Mystifying Mosaic?
Manatees are unusual in many ways; they are the only known vegetarian aquatic mammal. Their unique combination of features makes them look like mosaics—creatures that appear to be pieced together from parts of other kinds of animals.
Their unique combination of features makes them look like mosaics—creatures that appear to be pieced together from parts of other kinds of animals.
Manatees have a sensitive trunk like an elephant’s, only shorter; they digest their food like horses; and they have sensory hairs over their entire body, like cats and dogs have on their faces. They also continually replace their teeth like sharks.
Creationist Dr. Kurt Wise suggests that mosaics are explained well by the creation model.1 They appear designed to live in “in-between” worlds, places that might seem unfit for many creatures. God in His infinite wisdom and His plan to “fill the earth” made manatees to live in the in-between world of warm coastal and inland waterways, where fresh and salt water often meet.
Flotation Food and Traveling Teeth
Manatees’ large, barrel-shaped bodies are not streamlined for fast swimming but are perfect for a slow-moving, grazing animal. The large body also helps keep them warm, since they have very little body fat and their metabolic rate is low. Even so, manatees can live only in warm waters.
A large body does have one drawback, however—it can be difficult to move rapidly up and down in the water. Many other sea creatures have special designs to help them rise and sink; for instance, fish have swim bladders that they can fill with air, and sharks have buoyant oils in their liver to prevent them from sinking. Manatees’ solution is a high-fiber diet. All that fiber produces a lot of gas in their gut, which they retain to help them float or pass to sink. And they must retain or pass a lot of gas to move their great bulk—their intestines are 150 feet (46 m) long! In fact, a constipated manatee can’t dive. Also, their lungs are almost as long as their entire body. All that internal “air” helps them control their buoyancy.
On the other hand, manatees’ heavy skeleton helps them dive. Researchers have determined that their bones are denser—and thus heavier—than other animals’ bones. Their dense rib cage, especially, helps them dive mouth first toward their favorite sea grasses and sea plants.
Many sea grasses have a lot of sand and grit mixed in them, which wears down teeth. So manatees’ teeth are constantly replaced, conveyor-belt fashion, as new ones grow in the back of their mouths and move forward. That’s more like a shark than other mammals.
Slow-moving manatees must have some way to detect danger in time to avoid it. Curiously, their eyesight and hearing do not appear to be as good as other aquatic mammals’, and they do not use echolocation or detect electrical signals. Again, the manatee has a unique solution—whiskers. The technical name for these whiskers is vibrissae.
Many mammals have sensitive vibrissae. Your cat or dog has about 50 on its face, and squirrels have vibrissae on their paws, elbows, and knees. But the manatee is the only creature that has vibrissae on its face and spread all over its body.
About 600 fine vibrissae are concentrated near their mouths, with nearly 1,500 thicker ones on their faces and another 3,000 on their bodies. Some vibrissae on the face are connected to over 50 nerve cells each, making them extremely sensitive. Fascinatingly, researchers have also found dedicated bundles of nerves in the brain associated with each individual vibrissa! Manatees clearly use their vibrissae to feel plants on the bottom of the waterways, and sometimes they use very thick, stiff vibrissae to actually grab a plant and pull it out of the seafloor. But they appear to use their body vibrissae to sense movement in the environment, and maybe even to detect sound.
How Did They Survive?
According to old-earth scenarios such as evolution, some manatee groups have been around for several million years in ocean waters. But such slow animals are in constant danger of being eaten. In fact, in the eighteenth century, the Steller’s sea cow (a relative of manatees that lived in cold waters near Alaska and the Bering Strait), was hunted to extinction in just thirty years. It certainly seems that young-earth creation better explains the survival of seemingly defenseless, slow-moving creatures like the lumbering manatee.
God designed this gentle creature for the environment He put it in. But because of Adam’s sin, the world is not a perfect place. Manatees’ habitat is shrinking, and many manatees are killed and maimed every year from violent collisions with boat propellers as well as other human-related factors. God’s command to Adam to subdue the earth includes the responsibility to exercise proper management of His creatures. (Genesis 1:26–28)
Did You Know . . .
- Manatees are part of a group of animals called the sirens, which includes the dugong and the Steller’s sea cow. All these animals are probably part of the same created kind.
- Manatees’ scientific name, sirenia, comes from sirenum, a group of rocky islands in the Mediterranean that played a big role in Greek mythology. Legend has it that many sailors met their death after being lured by mermaids (also called sirens) to the rocky waters.
- Manatees played a part in several legends. In fact, some people believe the legend of mermaids was inspired by manatees and their kin.
- Manatees are curious animals, and the waterways they live in host a lot of commercial and recreational traffic. For these reasons, human-related factors are the leading cause of death among manatees.
- Many ancient people groups valued manatee skins. In fact, some biblical scholars believe the skins of dugongs (a relative of the manatees that lives in the coastal waters of the Middle East), were used as a covering in the tabernacle (Exodus 25:5).
Size: Up to 13 feet (4 m)
Weight: Average 1,300 pounds (590 kg) with records exceeding 3,500 pounds (1,590 kg)
Habitat: Shallow, slow-moving rivers, estuaries, saltwater bays, canals, and coastal areas in the southeastern United States, mostly in Florida; coastal and inland waterways of Central America; and along the northern coast of South America.