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Etruscan Shrew (Suncus etruscus)
Alright, this is a little bit of a stretch for Etruscan week, but the Etruscan shrew (Suncus etruscus) is fascinating! It is the smallest mammal by mass weighing an average of only 1.8 grams (0.063 oz) (although there are certain bats with smaller skulls). The tiny creature does indeed live in what was once Etruria…although it admittedly also lives around the Mediterranean, throughout the Middle East, North Africa, Asia Minor, across Southeast Asia, and down into Malaysia. There are also invasive colonies in Nigeria (though goodness knows how they got there).
Etruscan Shrew Range
The shrew has a fierce metabolism: its little heart beats 1511 times per minute (25 beats a second). It must eat up to twice its own body weight every day to stoke its internal fires. I like food–but I would wear down fast eating a thousand hamburgers a day. Once I watched a documentary about the top ten super predators—and shrews weighed in at number one. They only eat live food which they catch—and they catch between 20 and 30 prey animals a day. This becomes all the more impressive when one considers that they eat insects (which have wings and are sometimes bigger than the shrew) as well as spiders and myriapods which are armed with terrible stings and venoms. Additionally the shrew dines on immature amphibians, baby rodents, worms, and larvae.
Etruscan Shrew with Snail
Etruscan shrews are largely nocturnal and crepuscular. Because of their poor eyesight, they have acute hearing, highly sensitive whiskers, and an amazing sense of smell: indeed, their long tin noses are mobile and can move about quite sinuously. In winter their fur grows long and they sometimes undergo periods of temporary hibernation when their body temperature drops down to 12 °C (54 °F). They are only social during mating season when a pair will live together through the 27-28 day gestation and until the cubs are independent (which is when they are three to four weeks of age). Litters range from two to six cubs. Because they are so small (and so widespread), Etruscan shrews are preyed on by all manner of snakes, cats, lizards, birds, and other predators. Their particular bane seems to be owls. Naturally, none of these predators are as dangerous to the overall species as humankind is. Etruscan shrews now have a non-contiguous range because of agriculture and habitat loss (although they seem to enjoy human ruins). They live to two years of age in captivity—although owls usually prevent death from old age in the wild.
The Etruscan Shrew is cute in its own way…
If we were not so jaded, we would recognize how remarkable and intense the Etruscan shrew is. Just writing about it, I feel like I have been describing an alien lifeform—a clever cunning creature which fits in a teaspoon. Except when it hibernates, it must endlessly devour. We will return to the art and society of ancient Etruria tomorrow, but right now spare a moment to reflect on the extraordinary nature of our strange mammal kin!
Lesser Shrew And Common Shrew (Archibald Thorburn, 1903, watercolor on paper)
One of my favorite aspects of art is the foreground—the tiny and insignificant items pictured there frequently highlight the larger themes of the work (while wedding the larger figures to a microcosm of tiny dramas). This is true unless the painting is all about the foreground, as is frequently the case with the works of Archibald Thorburn (1860-1935) a Scottish painter who specialized in watercolor paintings of wildlife—particularly birds and small creatures. Here is a wonderful watercolor painting of two small shrews encountering a potentially dangerous larger shrew within a tiny landscape. The pebbles and grass blades become forests and boulders for the tiny insectivores as they size up this strange encounter. Of course there is a foreground in this tiny painting as well: a common wildflower grows into the composition from the right corner. The tiny salmon petals of the little flower lend color and drama to the scene (while reminding the viewer to always look for beauty, even in the world underfoot).
During the Mesozoic, the age of dinosaurs, mammals were widespread, but they kept a low profile so as to avoid the baleful attention of the great reptiles. A fossil of one of these furtive early mammals was discovered last November (2011) in Argentina. The creature was christened as Cronopio dentiacutus, and not only does the animal’s partial skull give us a window into mammalian form in the late Cretaceous it also provides a special treat for regular readers of Ferrebeekeeper, for like the Smilodon, the walrus, and the Odobenocetops, Cronopio has distinctly pronounced saber teeth (despite being a small scurrying squirrel-like creature).
A model of the Cronopio dentiacutus–which was only 10 to 15 cm (4 to 6 inches) long.
Cronopio dentiacutus was probably actually more shrew-like than squirrel-like and used its saber teeth for hunting insects. Based on its large eye sockets, Cronopio most likely hunted its prey at night (when it could also more easily escape the attention of the dinosaurs and other larger predators.
Julio Cortázar, Argentine Surrealist author
Cronopio dentiacutus takes its species name from a Greek phrase meaning sharp teeth, but the origin of its genus name is rather more literary. The Argentine surrealist writer Julio Cortázar wrote several books about abstracted categories of fictional entities and the Cronopio was the idealistic but disorganized type of being (as opposed to rigid, highly-organized “famas” and indolent, dull “esperanzas”). It is unclear what creative/idealistic features of this insectivorous early mammal struck the fancy of the discovering paleontologist to provoke such a name, but it is nice to see scientists pay Argentine belles-lettres such an acknowledgement.
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