There are some vicious plants on the planet. Everyone knows to avoid plants that scrape, stab, and sting, and of course there are many that attract flies, moths, wasps, butterflies, beetles, centipedes, and ants. Then there are those like the rat-eating pitcher plant that can devour entire mice, frogs, and rats.
Meat Eater of the Mountain
If you're not familiar with this fascinating, fauna-feasting flora, it's likely because it was only discovered in 2007 when a group of botanists gained funding to research the plant after missionaries returned with tales of a large, meat-eating plant they’d seen in the jungle. Lead by Stewart McPherson, Volker Heinrich, and Alastair Robinson, the expedition headed out and located the rumored plant on Mount Victoria in the Philippines after two months of searching. Once they returned, they spent three years comparing their mysterious specimen to similar plants before publishing their work in the Botanical Journal of Linnean Society.
Pitcher plants are nothing new to the field of botany. You may be familiar with the venus fly trap, for example. Pitcher plants are defined by their tubular-shaped leaves and deep cavities that are filled with an acidic mixture. Similar to stomach acid, the liquid breaks down, or digests, the animal in its grasp. Renowned for their ability to attract and subsequently capture prey, pitcher plants typically munch on unsuspecting insects that fly or crawl into their trap.
Dubbed Nepenthes attenboroughii, the rat-eating variety also eats bugs, but its capacity to consume larger prey like entire rodents is a rare capability. McPherson, Heinrich, and Robinson decided to name the plant after Sir David Attenborough, a broadcaster and naturalist who inspired the trio, their team, and generations of nature lovers. No word on whether Sir David is also able to digest entire rodents.
Carnivore Hiding in Plain Sight
The pitcher plant is an impressive example nature's transformative power on display. It begins life as a leafy plant, the traps appear to be the same as any other leaf as they shoot out. Then the curled structure unrolls, opening into a leaf shape. Next, a tendril grows out from the end of the leaf and reaches towards the ground or climbs up nearby foliage in a manner similar to a grape or hop vine. Once it touches the ground or other secure surface, the end of the innocent looking tendril expands into a cup and then a larger reservoir with a leaf-shaped lid. The shape is a little like a coffee creamer with hinged lid.
Deceptive with the colorful tropical appeal, everything about the rat-eating pitcher is designed to draw in prey. Starting at the top, the nectar-laced mouth secretes the sweet syrup to entice their victims. Coupled with benign-looking colors, animals have no idea about the trap ahead. With a waxy interior what begins as a tempting sample of nectar results in a water-slide ride to the bottom of the chute. The tubular trap, called the pitcher, is shaped like a water pitcher so once the bait is successful and the rodent slips in for a quick drink, they are unable to scramble out. Even if a mouse could claw its way to the top of the sleek-sided cavity, it would take skill and a decent dose of luck to make it past the ring of thorny barbs at the top of the structure. Then there is the fact that the enzymes begin breaking down the creature as soon as they plunge into the fluid. Additionally, the saplike stickiness of the substance defies every effort of escape.
The rat-eating pitcher plant is the second-largest discovery in the pitcher family. Technically pitcher plants include examples from a few families rather than one family and encompass around 600 species. The title for the world's largest pitcher plant goes to another variety of rat-eating pitchers, nepenthes rajah, which was discovered in 1858 by British naturalist Hugh Low in Borneo.
At least 30 species of pitchers are exclusive to the Borneo region. Similarly, the rat-eating variety has only been seen in Palawan in the central Philippines. The scarcity of these plants is explained by the very specific conditions in which they grow. Not only is success dependent upon a balance of temperature and humidity, but also receipt of the proper nutrients. Since much of the ground is sandy or rocky and void of quality-rich soil, many of the required nutrients needed to survive come from the animals they are able to ingest. So in addition to protecting themselves from attack, enticing and digesting their prey is a key component of their survival.
This struggle in obtaining nutrients is one of many reasons that the rat-eating pitcher plant is on at least one list of the top 100 most threatened species in the world and also helps explain why a plant this large and dramatic went undiscovered until the 21st century.