Hippopotamus—Territorial Terrors by Tom Hennigan

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Those pudgy pachyderms might look cute in the zoo, but don’t cross one in the wild. God specially designed them to fill their place in the river—and they guard it with everything they’ve got.

Like a Weed Eater, it spewed grass every which way—but this was no Weed Eater. Believe it or not, I was looking at the south end of a north-facing hippo who was dumping the leftovers of his latest meal. The tail whipped back and forth so rapidly it jettisoned grassy waste in all directions, evoking loud chuckles from the amused crowd.

Though we find the big hips and quirky walk of the common hippo funny at a distance, ignoring his other characteristics could be fatal if we stumbled across one up close. With an average adult length of 14 feet (4 meters) and weight of 7,000 pounds (3,200 kg), the hippo ties the white rhinoceros as the second largest land mammal in the world (after the African bush elephant), and it is the most deadly to humans. Hippos’ ferocity is legendary; they kill more people than any other mammal, and adult hippos carry vicious scars from hard-fought battles with one another.

With their sometimes humorous behavior and primarily vegetarian diet, hippos are easy to picture in the pre-Fall world where humans and animals ate only plants, and relationships were in harmony. However, the Bible is clear that our sin brought God’s curse on this world (Genesis 3 and 6), and the world today is marked by disharmony. Even the vegetarian hippo occasionally eats other animals, and hippos have become aggressive in order to survive.

The common hippo (Hippopotamus amphibius) has webbed toes, lives in Central Africa, and spends a lot of time in the river (hippopotamus is Latin, from the Greek for “river horse”). Hippos are highly territorial and mark their realm by urinating and defecating in as large an area as possible. This explains the Weed-Eater behavior. Males vie for control of both space and females, and territorial battles can be vicious. Two unique design features equip hippos for the demands of their world.

Superior Sunscreen and More

For centuries people have thought that hippos sweat blood. They have also observed that the deep wounds suffered in territorial battles rarely get infected. Could there be a connection? It turns out that “hippo sweat” is neither sweat nor blood. It is actually a thick, clear fluid produced by glands in the skin that coats their bodies and hardens in just minutes. It looks like blood because it turns pink to red-brown as it hardens.

The hippo’s chemical coat has a brilliant multi-purpose design. It serves as a long-lasting coolant that blocks most ultraviolet radiation. It also prevents bacterial growth, which explains why battle scars are rarely infected.

Recently, scientists have identified two unique pigments in this substance, hipposudoric acid and norhipposudoric acid, that appear to hold the secret to its amazing properties. This discovery is so promising that manufacturers and scientists are brainstorming ways to reproduce the chemistry in a long-lasting, antibiotic sunscreen.

Amphibious Communication

Hippos may be the only animals that communicate amphibiously by sending and hearing messages in both air and water simultaneously. Airborne sounds start in the voice box and exit the nostrils. They are so loud that from 15 feet (4.6 m) away the sound is as powerful as a rock concert.

But hippos sound off underwater as well. Their voice box is designed with a fatty layer under the jaw to transmit sound from the hippo’s airway to the water. Because fat has the same density as water, this fatty layer enables the sound to remain clear and travel long distances.

Hearing is a different matter. If you have ever tried to talk to others underwater, you probably noticed that it is very hard to understand them. Sound doesn’t normally transfer efficiently from water through your ear canal to the middle ear. So God gave hippos an alternative underwater hearing method. Hippo jaws are connected to the middle ear, similar to dolphins’ jaws, so that sound vibrations can be transferred directly from the jaw, bypassing the ear canal. This allows them to hear clearly underwater.

Since sound travels much faster through water than through the air, sounds will reach the hippo’s middle ear twice. Hippos may be able to determine distances by the difference between when they hear a sound in the water and when they hear it in the air. This simultaneous hearing may help them communicate territorial boundaries over large distances and minimize fights with other hippos.

Hippos remind us that though the world is cursed because of man’s sin, the Creator remains Jehovah Jireh, God our provider. If His grace is extended to a hippopotamus, how much more grace and provision does He desire to shower upon His image bearers?

Did You Know . . .

  • Hippopotamuses are grouped in the order Artiodactyla, which is Greek for “finger toe.” This name refers to how their weight is evenly placed over the third and fourth toes. That is why they are called even-toed animals.
  • The other living hippo species is the pygmy hippo (Hexaprotodon liberiensis), which gives birth both on land and underwater. They reach lengths of 5–6 feet (1.5–2 m) and weigh 350–600 pounds (160–270 kg).
  • Common hippos can run at speeds of 15 miles (24 km) per hour, walk or run on the bottom of rivers and lakes, and hear each other a mile away.
  • Adult hippos can open their mouths almost 180°, chow down 90 pounds of grass per day, and store two days’ worth of food in their stomachs.
  • Common hippos can go without eating for 3 weeks.
  • Because hippos regularly float in the water, other creatures, like turtles and baby crocodiles, may use their backs as decks for catching the sun’s rays.
  • Some birds may take advantage of floating hippos and go fishing off their backs.
  • A group of hippos may be called a siege, a pod, a herd, or a bloat.
  • Both common and pygmy hippos are at risk of becoming endangered species.
  • Both common and pygmy hippos generally give birth to one baby every two years.

PHYLUM: Chordata
CLASS: Mammalia
ORDER: Artiodactyla
FAMILY: Hippopotamidae
GENUS: Hippopotamus
SPECIES: H. amphibius
SIZE: 14 feet (4 m) long
DIET: Mostly grasses near permanent rivers and streams
HABITAT: Estuaries and rivers in Sub-Saharan Africa

Tom Hennigan is associate professor of biology at Truett-McConnell College, where he teaches organism biology and ecology. He is co-author of the newest edition of the Wonders of Creation series, The Ecology Book.

http://www.answersingenesis.org/articles/am/v8/n4/hippopotamus