Myotis lucifugus

Inside a public building near a lake, on a wall built of vertical yellow pine boards, knots in the wood show dark. One spot near the ceiling is bigger and darker than all the rest. 

It is not a spot. It is a sleeping bat. A little brown bat, Myotis lucifugus. A female. 

Movement is just barely visible in the little bat's back as she breathes in and out. Her flat body is pressed against the wall, her pale belly hidden, her chocolate-brown back exposed to help her blend in. The brown on her ears and the fur surrounding her eyes, nose, and mouth is a darker shade. Her long toes are tucked into a crack in the wooden wall, gripping even as she sleeps.

Inside the backwards-pointing toes, tendons are constantly being pulled tight by the weight of the hanging body. The bat will only fall if she chooses to let go while awake. 

Evening comes down. The sun sinks, casting the already dim room into deeper gloom.

The bat wakes.

Her jaws open wide. A lining of tiny bright-white teeth are visible in her pink mouth, looking rather fearsome as she yawns. 

She shifts in place, looking left, right, up and down, all around. Her movements are so many, so small, and so quick they appear tremulous. Two ears, the bat's largest facial feature, rise from the back of her head on both sides. They are shaped like small leaves, rounded and cupped forward, tapering to a point at the apex. 

The ears rotate as the bat emits ultrasonic squeaks, higher pitched than human hearing can detect.

Though her eyes can see, the little brown bat is studying her surroundings with sound, which tells her more. Her hearing is more precise and reaches farther than her sight.

High decibels—in other words, loud noises—burst from the little bat's mouth and speed away. 

Sound does not travel in only one direction, like a ball being thrown; it behaves like a vapor, diffusing and spreading in every direction. Once the soundwave strikes a surface other than the air it travels through, it creates new sound: an echo. 

The echo sends out its own spreading cloud of sound, falling slightly in frequency the farther it travels. The echo is what the bat listens for. Some species of bat cannot even hear the noise they make, only the echoes their noise produces. In others, the eardrum closes at the moment they echolocate; if it did not, they would damage their own hearing, so loudly do they cry out. 

The echoes come back, informing the little brown bat that there is no predator waiting to catch her, and she has a clear flight path to the opening through which she came in this morning. 

She stretches out her right wing. A moment ago, it looked small and insubstantial, like a shred of burnt-black skin left clinging to the big bone that juts forward and sports the thumb. Now, the limb of flight unfurls.

The membrane turns from black to a strange color between brown, red, and amber. Four lines of bones run between the strong but delicate double layer of wing skin: the bat's fingers. Just like a human, a bat has five digits. What would be pointer, middle, ring, and pinkie fingers on a human all support the wing skin in a bat. 

The little brown bat spreads her fingers and stretches her arm, which is much shorter, though more substantial, than her fingers. Her right fingers close, folding the wing back, and she stretches her left hand-wing. That is the overarching name given to all bats by scientific-minded humans: Chiroptera, hand-wing. 

Several alternating stretches later, Myotis shrugs. Tendons running from her shoulders into her arms and fingers snap her wings open as her shoulders begin forward movement. She releases her toes from the crack they grip, and falls.

Myotis curves her fifth finger, which stretches straight from the front of the wing to the rear edge, to catch the air. Her legs spread wide, extending the rest of the wing membrane that encases her bony tail. In the moment she slows, flapping begins. The limbs move in a repeating figure-eight pattern: forward, up and over, down, back and up and over forward again. The movements can push Myotis through the air at up to three miles an hour.

She gets up speed and then tucks her wings tight for a moment, hurtling through the narrow gap left by a door that won’t latch. The opening is only a few inches wider than her body, much smaller than her wingspan. She does not even brush the sides.

Myotis exits the building by the lake and darts out into the deepening evening. 

A few lights on poles glow around the campground, attracting bugs, which attract bats. They circle the pools of light and food, zipping through one after another. 

Myotis angles into the light, singing out as she flies. Around five calls come from her mouth every second. 

Prey bounces back an echo: it's coming back faster and faster. She speeds up her cries, until they are constant and the moth she has singled out is nearly in her jaws.

It dodges to the right. Myotis's head turns, still following it with a repeating shriek. She sweeps her right wing forward, abandoning the usual flapping motion. Her thumb and first finger grasp the moth and bring it to her mouth in a flash of movement. Her teeth close on the abdomen, and she flies to a place not very far away where she can hang and hold her prize while chewing off bite-sized pieces. Many times Myotis’s prey are captured one at a time, even if they are small. 

Weeks flutter by like the leaves falling from the trees The bats travel to a cave. This is the time for mating, but not for conceiving. The females fall into torper first, and the males provide what is needed for the new generation to come. Then they, too, fall still and quiet. 

Myotis’s heartbeat slows and her body temperature drops. She sinks beneath regular sleep into the mysterious near-death of hibernation. 

Inside the little brown bat’s uterus, tiny, strong seeds of life align themselves to face a particular section of the uterine wall. A substance is secreted here that will nourish the little seeds all through the winter to the spring awakening. 

There is no place ready now for the seeds to fertilize. That is also dormant, and will be until rising temperatures and ingestion of new food trigger completion to begin. No other female mammal in the world can keep their seeds of life this long and keep them vital, too.

Until arousel, months from now, Myotis will rest, all within her womb fallen out of time.