Marcanos Solenodon

Marcano's Solenodon—Marcano's solenodon, like its living close relatives, was a nocturnal predator of invertebrates and other small animals. (Phil Miller)

Scientific name: Solenodon marcanoi Scientific classification:

Phylum: Chordata Class: Mammalia Order: Soricomorpha Family: Solenodontidae When did it become extinct? It is not known when Marcano's solenodon became extinct, but it was probably after the Europeans first reached the New World at the end of the fifteenth century.

Where did it live? The remains of this animal are only known from the island of Hispaniola.

Hispaniola, along with Cuba and Jamaica, make up the Caribbean island group known as the Greater Antilles. All these islands once had their own distinctive fauna, the ancestors of which somehow reached these islands from North, Central, and South America. Today, the native fauna of the Greater Antilles is a shadow of what it once was due to the arrival of humans: first, Amerindians, and much later, Europeans.

The solenodons have suffered badly at the hands of humans and their introduced animals. One species, Marcano's solenodon, a native of Hispaniola, is actually extinct and is only known from skeletal remains. Although we only have bones to work with, we can safely assume that Marcano's solenodon was very similar to the surviving solenodons in both appearance and lifestyle. Solenodons are a fascinating group of animals. In appearance, they look like large, well-built shrews and are about the same size as a very large brown rat (Rattus norvegicus), with reddish brown fur; a long, mobile snout; tiny eyes; and a long, scaly tail. The limbs of the solenodons are very well developed and the digits are tipped with long, sharp claws.

Like the living solenodons, Marcano's solenodon must have been a burrowing animal that only ventured from its daytime retreat to hunt and look for mates when night fell. This unusual animal was undoubtedly a carnivore, and the staple of its diet must have been insects and other invertebrates, including earthworms, centipedes, and millipedes, all of which were found by rooting through the leaf litter and the soil and by tearing up rotten logs on the forest floor. Marcano's solenodon was large enough to kill and eat vertebrates, such as small reptiles, amphibians, birds, and mammals, when the opportunity arose. One of the most fascinating things about the solenodon is its ability to secrete and use venom. Like almost all vertebrate venoms, solenodon venom is actually modified saliva. It is a mixture of various proteins produced by the salivary glands, and it is introduced into the body of the prey when the solenodon bites. The solenodons even have modified teeth for delivering this lethal cocktail. The large incisors on the lower jaw of the animal are equipped with a groove that channels the venom into the wound made by the teeth. Exactly how the solenodon venom kills the prey is unknown, but the venom produced by the American short tail shrew (Blarina brevicauda) causes the blood vessels to expand, leading to low blood pressure, paralysis, convulsions, and eventually, death. As the solenodons are closely related to the true shrews, we can assume that their venom has a similar effect.

Not only do the solenodons produce venom, but they also produce potent secretions from the base of their legs, which is said to have a strong, goatlike smell. Exactly what these secretions are for is unknown, but it is highly likely that they use this pungent aroma to mark their territory and communicate their willingness to mate to members of the opposite sex—such is their reliance on their sense of smell. Attracting mates with scent is important for a small, scarce mammal with poor eyesight. Exactly when these animals mate is unknown, but the females are receptive to the advances of males about every 10 days. When they meet, solen-odons can be vocal animals, broadcasting their intentions with puffs, twitters, chirps, squeaks and clicks, but when the act of mating is over, the male and female will quickly part company.

The female solenodon only gives birth to one to two young every year, an astonishingly low number for a small mammal. She gives birth to her young in a subterranean nest in the burrow system she excavates with her powerful forelimbs. At first, the young are blind and naked, but they grow quickly, and before long, they are able to accompany their mother on her nocturnal forages. Amazingly, when baby solenodons accompany their mother, they never let go of her greatly elongated teats, so when the baby is really small, it simply gets dragged around, but as it grows, it is able to trot alongside its mother with the teat clasped firmly in its mouth. The young solenodon stays with its mother for several months, and even when it has ceased hanging on to her pendulous teats, it follows her around and licks at her mouth when she is feeding to learn the food preferences that will help it survive as a solitary adult.

As interesting as these insectivorous mammals are, they are completely defenseless against humans, and Marcano's solenodon has already been lost forever. The remains of this solenodon have been found with the bones of brown rats; therefore the species was still around when Europeans first reached Hispaniola as rats only reached the Greater Antilles aboard the ships of Columbus and later explorers. Amerindians reached Hispaniola thousands of years before Columbus arrived, and they appear to have had little effect on the populations of the Solenodon. As these animals are small and nocturnal, the first humans to settle Cuba probably only saw them rarely. The disaster for the solenodons, especially Marcano's solenodon, were the animals introduced by Europeans. Apart from occasionally falling victim to boa constrictors and raptors, solenodons had no enemies before the arrival of Europeans, and as a result, their defenses against cats and dogs are pitiful. If pursued by one of these predators, the solenodon stops in its tracks and hides its head between its forelimbs. Disastrously ill equipped to cope with the influx of new predators, Marcano's solenodon was wiped out, and the remaining Hispaniolan and Cuban species are now woefully endangered.

♦ The solenodons are an ancient group of insectivorous mammals that have changed little in millions of years. They are known from North American fossils between 26 and 32 million years old.

♦ There is some debate over the closest living relatives of the solenodons, but they are probably most closely related to the primitive tenrecs, another group of unusual insectivorous mammals found on the island of Madagascar and in parts of western and central Africa.

♦ Apart from the solenodons, only a handful of other venomous mammals are known: the platypus (Ornithorhyncus anatinus), Eurasian water shrew (Neomys fodiens), short-tailed shrews of the genus Blarina, and slow loris (Nycticebus coucang). Why there should be so few venomous mammals is an interesting quandary, but it is probably because mammals have evolved a number of ways of catching their prey swiftly and efficiently. Even the best venom cannot bring about death immediately.

Further Reading: Woods, C. "Last Endemic Mammals in Hispaniola." Oryx 16 (1981): 146-52; MacFadden, B.J. "Rafting Mammals or Drifting Islands?: Biogeography of the Greater Antillian Insectivores Nesophontes and Solenodon!' Journal of Biogeography 7 (1980): 11-22; Morgan, G. S., and C. A. Woods. "Extinction and Zoogeography of West Indian Land Mammals." Biological Journal of the Linnean Society 28 (1986): 167-203.

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  • Camelia Labingi
    What are some learned behaviors the solenodon have?
    8 years ago
  • piia
    Are marcano's solenodons extinct?
    8 years ago

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