Photo by Will Gillespie.

November 1, 2019

Of Bats and Etymology

Of the 13 bat species of the family Vespertilionidae which frequent Illinois, five share the genus name Myotis, a term derived from Greek mys meaning “mouse” and ous meaning “ear.” If bats could express indignation, the Myotis bats would now be furrowing their foreheads and harrumphing, “We bats are not members of the Rodentia!”

Bats are classified under the order Chiroptera. We recognize that chiro is Greek for “hand,” as in the word “chiropractic”; and ptera, as in “pterodactyl,” means “wing.” “Winged hands,” that nails it! Four elongated finger bones serve as the struts operating to either stretch or fold skin; thus, with the extensions of this soft yet tough skin bilaterally connected to its body and limbs, the bat becomes the only mammal capable of sustained flight.

From just a scientific name and a bit of etymological knowledge, we can garner much about the nature of a creature.

In actuality, mys and ous serve appropriately in naming, for example, Myotis lucifugus the little brown bat since its ears are naked (without fur) and are bluntly rounded, resembling a mouse’s ears. Unlike the mouse, however, the bat uses its ears as sonar antennae during its nightly pursuance of insectivorous meals. The bat emits – sometimes up to about 50 times per second – supersonic cries. As those high-frequency sound waves bounce off objects, the bat’s ears receive the echoes and the bat’s mind interprets.

Serving to improve the efficacy of the echolocation process, the tragus (an elongated flap in the frontal part of a bat’s ear) contributes to the production of a secondary echo entering the ear canal, and the delay of this echo seems to help encode the vertical direction of the sound source.

To prevent from hearing the emanations of its own voice, the bat can momentarily contract a minute muscle in its ears. To quickly detect sounds coming from various directions, the bat can rapidly change the shape of its ears.

By the way, the etymology of the little brown bat’s species name lucifugus looks like this: [Latin lux “light” + fugio “to flee”]. Light flee-er. How perfect is that! Nocturnal.

Some species names suggest color. The yellowish in the fur of the Tricolored Bat is signified by subflavus [L. “below” + “yellow”]; the brown of the Big Brown Bat by fuscus; and the silvery or ash-color of the Hoary Bat by cinereus.

A small brown bat with large ears hanging from the stone ceiling of a cave.
Big-eared bat, Corynorhinus spp.

Here’s an analogical riddle: Rhinoceros spp. is to the rhino as Corynorhinus spp. is to what? Hint: Both genus names make an implication about a certain facial feature. Answer: Big-eared bat. How so?

Corynorhinus [Gr. koryne, “club” + rhis, “nose”] suggests the paired glandular masses which adorn the nose or muzzle of the lump-nosed bats or now more commonly called big-eared.

What ears those are! At 1¼ inches long, the bat’s large ears reach the middle of its body when laid back. This bat need not rely on echolocation only; it can passively listen to locate stationary prey as it forages by both gleaning and aerial hawking, generally at about one meter off the ground in forested areas.

Giving us insight into the reason for the Indiana bat’s vulnerability to the fungal disease White-Nose Syndrome (WNS) is its species name sodalis [Latin, “companion”] which points to the bats’ tendencies to hibernate together in great masses. The fungus insidiously grows while the bat’s body temperature is quite low and then spreads through a colony while the bats are in contact with each other or with contaminated surfaces, generally within hibernacula such as caves or mines. The disease causes wintertime wakefulness leading to starvation and death. Thus, the species name of the fungus “Pseudogymnoascus destructans” is truly fitting, unfortunately.

One of the bat species with no known victims of WNS is the evening bat of the genus, Nycticeius [Gr: nyx “night” + eius “belonging to]. So, like Nyx the Greek mythological goddess of the night, the evening bat could be called the aristocrat of the nighttime skies.

However, if the insects of those nighttime skies were articulate, they would not use the term “aristocrat” for a bat, rather “assassin!” As insectivores, the bats of Illinois are, of course, ecologically significant, but to what extent are they valuable to society? Stemming from a study of bats’ predation on adult corn earworms, a research paper “Bats initiate vital agroecological interactions in corn” (published in PNAS, 2015) suggests that as bats feed upon moths they arrest the insect’s life cycle enough to suppress the number of larvae or caterpillars and thereby prevent crop damage done by the larvae’s foraging and by the associated fungal growth. Thus, bats are beneficial in our pursuits of food production.

Bats eat bugs, so shouldn’t the etymology of a word describing bats be L. vulgaris? Hey, don’t get indignant! Use a dictionary. A synonym of “vulgar” is “common,” and common is what we hope bats will always be.

For years, Patty Gillespie shared her enthusiasm for language and nature and got paid for it at a public school and at a nature center. Now she plays outdoors as often as she can and writes for the sheer joy of it.

Share and enjoy!

Submit a question for the author