A new study from researchers at the University of the Witwatersrand found that the venomous puff adder viper can disguise its scent as well as its appearance, according to the Daily Mail. Large and beige-colored, the puff adder waits for its prey motionless on the ground until its ready to strike at it's victims or or it lays waiting for predators to leave the area.

The researchers trained four dogs to detect the snake's scents by sniffing a cloth that had touched one of the snakes and then locate the snake. Afterwards, the dogs were given samples of the snake with environmental samples and two "clean controls."

The dogs were made to track down five different species of "active foraging snakes," who take action to hunt their prey as opposed to waiting like the puff adders. The results showed that dogs have no problem picking up on the scent of these snakes, showing more than 80 percent accuracy in finding them. However, when it came to locating the puff adders, either wild or captive, the dogs had no success picking up on their scents.

With no success using dogs, the researchers conducted the same tests on meerkats that mastered the same training one month faster than the dogs. Similarly, the meerkats had no problem finding active-foraging snakes using scent trails, but could not do so for the puff adders.

The research conflicts with previous notions that odors emanate from all metabolizing animals, although the slow metabolism and body temperature of the puff adder could help it decrease its release of scent compounds.

The findings were published in the Dec. 16 issue of Proceedings of the Royal Society B.