Animal Architects

These aquatic rodents build their structures out of sticks or wood they cut with their teeth. They can also build them with mud or use a combination of both materials. Some beavers even include rocks in their design to provide more support so they can make the dams higher.

Beaver dams in the Rocky Mountains are often hundreds of feet wide and a few feet high. A well-constructed dam holds back water to create a pond or wetland where the plants the beavers like to eat can grow. Beavers often build more than one dam. “They might build a whole hotel complex of beaver dams,” says Westbrook, who studies beavers in the Rocky Mountains.

To harvest their materials, “beavers cut down things that regrow fairly rapidly and sprout more stems,” says Westbrook. Generations of beavers will use these regrown plants to repair and expand the dam. Some dams exist for centuries.

Beavers are water-dwelling rodents. They build their structures out of sticks or wood that they cut with their teeth. They can also use mud or a combination of both materials. Some beavers even use rocks to support their dams so they can make them even higher.

Beaver dams in the Rocky Mountains are often hundreds of feet across. A well-constructed dam holds back water to create a pond or wetland. That allows the plants the beavers like to eat to flourish. Beavers often build more than one dam. “They might build a whole hotel complex of beaver dams,” says Westbrook.

To harvest their materials, “beavers cut down things that regrow fairly rapidly and sprout more stems,” says Westbrook. As the plants grow back, future generations of beavers can use them to repair and expand the dam. Some dams exist for centuries.

Termites are the biggest animal excavator in the world. They dig underground tunnels to live in, heaping the waste dirt into piles to form massive towers. Some termite mounds can reach 17 feet high. But they aren’t insect apartment buildings. Many termite species build mounds to manage the airflow and help cool and heat the colony underground.

Researchers working in Brazil discovered an area two years ago covered in evenly spaced termite mounds. Each of the 10-foot-high towers were spaced roughly 70 feet apart over an area the size of Minnesota. These termites use the mounds differently: to transport leaves they collect and eat to their subterranean tunnels. Stephen Martin is an entomologist who studies insects at the University of Salford in the United Kingdom. While studying the mounds, Martin found that the termites may have started working on the mega structures 4,000 years ago!

The dirt is “just waste material being thrown out, and you have this nice mathematical relationship that the more you throw out, the higher [the mound] gets and the wider it gets as well. It’s the friction that holds the soil particles together,” says Martin. Since it rarely rains in the area, the mounds barely erode, leaving the ancient structures intact.

Termites are nature’s greatest excavators. They dig underground tunnels to live in and pile the extra dirt into massive towers aboveground. Some termite mounds can reach 17 feet high. Many termite species use them to manage the airflow and help cool and heat the colony underground. 

Researchers working in Brazil made an interesting discovery two years ago. They found an area the size of Minnesota covered in termite mounds that were evenly spaced apart. The towers were 10 feet high and roughly 70 feet away from each other. The termites crawled through them to bring leaves they had collected down into their tunnels to eat.

Stephen Martin is an insect scientist at the University of Salford in the United Kingdom. He found that the termites may have started working on these mega mounds 4,000 years ago! The dirt is “just waste material being thrown out, and you have this nice mathematical relationship that the more you throw out, the higher [the mound] gets and the wider it gets as well,” says Martin. Friction holds the soil particles together—and since it rarely rains in the area, the ancient structures stay intact.

Young male bowerbirds study construction for years. After observing more mature males for up to seven years, the birds strike out on their own and build elaborate structures to attract mates. The constructions are called bowers, which are dens made from twigs or vines.

There are two types of bowers the birds build: maypole bowers and avenue bowers. Maypoles are circular structures with a stick or tree in the middle. Avenue bowers are stick-lined aisles. The birds decorate their constructions with shells, rocks, or other materials females might find attractive.

The great bowerbird—the largest species—makes its structure by poking sticks that curve at the top into the ground, forming a tunnel for their mates to stand in. And they don’t use just a few sticks. These Australian birds create walls that can be 4 inches thick, 2 feet long, and 15 inches high.

Male bowerbirds in Australia build elaborate structures to attract mates. These dens, called bowers, are made from twigs or vines. Young male bowerbirds study construction for years. They watch more-mature males build their structures for up to seven years before striking out on their own.

Bowerbirds build two types of structures: maypole bowers and avenue bowers. Maypoles are circular structures with a stick or tree in the middle. Avenue bowers are long aisles lined with sticks. The birds decorate their constructions with shells, rocks, or other materials female birds might like.

The great bowerbird is the largest bowerbird species. Males makes their structure by poking curved sticks into the ground. The sticks form a tunnel for potential mates to stand in. The tunnel walls can be 4 inches thick, 2 feet long, and 15 inches high!

“It’s a massive amount of effort for them,” says Laura Kelley, who studies animal behavior  at the University of Exeter in the United Kingdom. The male bowerbirds create their bowers from scratch every year.

Sometimes a bird will have to build more than one in a season when a rival male dismantles its creation to eliminate the competition. “They just trash their bowers,” says Kelley, “and it takes them a long time to destroy them because they’re quite solidly built.”

“It’s a massive amount of effort for them,” says Laura Kelley, who studies animal behavior at the University of Exeter in the United Kingdom. The male bowerbirds create their bowers from scratch every year.

Sometimes a bird will have to build more than one bower in a season. That’s because a rival male may destroy its creation to eliminate the competition. “They just trash their bowers,” says Kelley. “It takes them a long time to destroy them because they’re quite solidly built.”