Cool Critter: Solenodon
Imagine a mammal that looks like a toupee-wearing cross between Yoda, an aardvark and an R.O.U.S. Now, imagine that this mammal can inject immobilizing venom through its teeth. That animal would totally rule the world, right?
Ummm, no. Meet the solenodon, a remarkably clumsy nocturnal insectivore with teats on (or at least very close) to its butt.
Solenodons are found on two islands in the Caribbean: Cuba and Hispaniola (the island shared by Haiti and the Dominican Republic).* The two species are distinct—they haven’t gotten it on in 25 million years—but they look similar. Both have long flexible snouts, teeny tiny eyes and long finger-like claws. They have naked tails and feet, but are otherwise covered in multi-colored fur. Hispaniolan solenodons are slightly larger than their Cuban cousins at a maximum length of 13 inches and a max weight of 2.2 pounds.
Solenodons have been around for-evah (in teenage time). Evolutionarily speaking, solenodons’ ancestors diverged from all other mammals 76 million years ago. They were one of the few native mammalian species to survive the European colonization of the West Indies, but times have gotten tough for these so-ugly-they’re-cute critters.
Like most extremely endangered animals, solenodons are threatened by habitat loss and predators and—like endangered whales—they just can’t reproduce fast enough. Solenodons live in forests, but with deforestation rampant on Caribbean islands (especially in Haiti where 99 percent of the original forest has been destroyed in the last 200 years), the little forest that remains is fragmented. For a relatively solitary animal, fragmented habitat can make finding a mate very difficult. Even if a solenodon is lucky enough to find a sexy solenodon of the opposite sex, the species’ reproductive rate is low. Females produce one or two litters of one to three offspring per year.
Scientists think that Hispaniolan solenodons were once one of the dominant carnivores in Hispaniola. But then the Europeans introduced dogs, cats and mongooses (mongeese?) to the island. Against these vicious—or at least competent—predators, the slow and awkward solenodon doesn’t stand a chance.
Of course, teetering on the brink of extinction doesn’t make a critter cool. But being the only living mammal that can inject venom through its teeth sure does. Solenodons have modified salivary glands in their mandibles (jaw bones). These salivary glands produce venomous saliva that the solenodon can inject into a victim through a grooved tooth—one of the lower incisors.
This venom-injection system is more of a self-defense tool than a hunting tool. Solenodons feed primarily on insects, worms, snails and plants—none of which really need to be subdued with immobilizing venom. Occasionally, solenodons supplement their diets with reptiles and chickens, but scientists aren’t sure if they actually attack and immobilize living animals or just scavenge dead ones.
Now, what’s up with those oddly-positioned teats? Most insectivores carry their young in their mouths, but young solenodons stay with their mothers for a long time and actively carrying the little buggers around could become tiresome. (And, of course, mama solenodons’ mouths are equipped with venom-injecting teeth, which may or may not immobilize their young.) Instead, young solenodons conveniently dangle from their mother’s teats in a highly evolved system known as ‘teat transport.’ The system is simple: baby solenodons grab on to their mother’s teats and hang on. Very young solenodons just hang as their mother drags them along. Older offspring grab a teat and walk under, beside or behind their mother.
*Until their re-discovery last year, scientists thought the Haitian population of solenodons was extinct. Now, they think the Haitian solenodon is a subspecies of the Hispaniolan solenodon—or perhaps an entirely different species.