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bat bat (bàt) noun
Any of various nocturnal flying mammals of the order Chiroptera, having membranous wings that extend from the forelimbs to the hind limbs or tail and anatomical adaptations for echolocation, by which they navigate and hunt prey.

- idiom.
have bats in (one's) belfry
To behave in an eccentric, bizarre manner.
[Alteration of Middle English bakke, of Scandinavian origin.]

bat, the only MAMMAL (order Chiroptera) capable of true flight. Numbering between 1,000 and 2,000 species, bats range in size from less than 1 in. (2.5 cm) to 15 in. (45 cm), with a wingspan of from less than 2 in. (5 cm) to 5 ft (150 cm). The body is furry and mouselike, with the forelimbs and extensions of the skin of the back and belly modified to form wings. Bats are most abundant in the tropics, and temperate species often hibernate or migrate to warmer areas in the winter. Most species frequent crevices, caves, or buildings, and are active at night or twilight; they roost during the day, often in large numbers and usually hanging by their feet. Most bats see well but depend on echolocation to navigate in the dark. Bats are fruit-eaters (fruit, nectar, pollen) or insect-eaters (fruit, insects, small animals, and fish); one species, the South American vampire bat, feeds exclusively on the blood of living animals, chiefly mammals.

• 25% of all mammals on Earth are bats
• Small animals like bats and shrews consume up to one and one half times their body weight in food every day.  For an adult male this would be like eating 1,000 quarter-pound  cheeseburgers a day, every day; or about 50 Thanksgiving dinners a day.
• Vampire bats regurgitate blood for bats that can't find food.
• African heart-nosed bats can have such a keen sense of hearing that they can hear the footsteps of a beetle walking on sand from six feet away.
• Austin, Texas, is home to the largest urban bat colony in North America.  At last count, an estimated 1.5 million Mexican free-tailed bats were living in the vicinity.
• The chinese character for "luck" is the same as the one for "bat".
• When bats emerge from a cave, they fly in a left-spiraling pattern to keep from bumping into each other.
• The world's smallest mammal is the bumblebee bat of Thailand, weighing less than a penny.
• The brown myotis bats young when born are equivalent to a woman giving birth to a thirty pound baby.
• The pallid bat of western North America is immune to the stings of scorpions and even the seven-inch centipedes upon which it feeds.
• Fishing bats have echolocation so sophisticated that they can detect a minnow's fin as fine as a human hair, protruding only two millimetres above a pond's surface.
• The Honduran white bat is snow white with a yellow nose and ears. It cuts large leaves to make "tents" that protect is small colonies from jungle rains.

Although it may seem that hanging upside down requires great strength, it's actually a sign of weakness. Bats arethe only mammals capable of sustained flight, but unfortunately for the bats, this special talent required  some developmental tradeoffs.

To fly effectively, they had to lose weight, largely in their hind legs. As a result, bats' leg bones are so thin that they can't walk on them. When not in flight, bats drag their bodies along the ground in a way that keeps pressure off of their delicate limbs.

Once the bat is ready to roost for the day, it locks its claws to a toehold and hangs upside down. This shifts thebody weight off of the legs and onto stretched muscles and tendons in the body.

The morphology of the megabats (the "flying foxes") displays primate overtones. The very idea that bats of any kind could be closely related to humans and apes was quickly dismissed by most zoologists. Flying mammals--- the bats---evolved only once according to mainstream theory; later the Order Chiroptera ("hand-wings") split into the small, mainly insect-eating microbats and the large, fruit-eating megabats. It was all pretty obvious; how could such complex, specialized animals have evolved twice?

But in Science Frontiers, there is ever the "however":

     "Arnd Schreiber, Doris Erker and Klausdieter Bauer of the University of Heidelberg
     have looked at the proteins in the blood serum of megabats and primates and found
     enough in common to suggest a close taxonomic relationship between the two
     groups. (Biological Journal of the Linnean Society, 51:359)"

An explanation might be that the similarities between the microbats and megabats represent adaptations to similar environmental niches rather than a common ancestry. (Timson, John; "Did Bats Evolve Twice in History?" _New Scientist_, p. 16, June 4, 1994.)

Does the black box labelled EVOLUTION contain a special subprogram for converting hands into membaneous wings whenever it seems profitable to do so? Or are we somehow missing a different sort of evolutionary process, perhaps something akin to the "directed evolution" suggested by some experiments with bacteria?

LACTATING MALE BATS
The scene is a Malaysian forest, where scientists are sampling canopy wildlife with nets:

"When the researchers captured a group of bats in a wide-ranging effort to survey animals that inhabit the Malaysian canopy, they were dumbfounded to see that the eight adult male Dyaks [a species of fruit bat] in the net all had visibly swollen breasts that produced milk upon being gently squeezed."

No other wild male mammals are known to give milk, although inbred domestic male goats and sheep will---rarely--- lactate. It is not known if the male bats actually nurse the young.

(Angier, Natalie; New York Times, February 24, 1994. Cr. J. Covey. Also: Francis, Charles M.,
et al; "Lactation in Male Fruit Bats," Nature, 367:691, 1994. Fackelmann, K.A.; Science News,
145:148, 1994.)

In their book _Anomalies and Curiosities_ of Medicine, G.M. Gould and W.L. Pyle record several cases of human males lactating and even suckling infants.

Bat sonar puts human technology to shame
October 12, 1998
Web posted at: 10:36 p.m. EDT
(0236 GMT)
WASHINGTON (AP) -- Bat sonar is so muchbetter than anything devised by human technology that the little creatures seem to enjoy rubbing it in.

"The bats were essentially turning to us and thumbing their noses," researcher James Simmons of Brown University said of tests aimed at challenging bats' sonar  ability.

Simmons' experiments, reported in Monday's issue of Proceedings of the National Academy of Science, are aimed at improving the Navy's sonar to help  detect mines under water.

Sonar systems send out a sound and then listen for the echo to bounce back. The time it takes to return tells how far away something is and in which direction. A major factor is the ability to differentiate between two echoes that arrive at almost the same time.

At the wavelengths under study, electronic sonar can differentiate between echoes about 12 millionths of a second apart.

With a lot of work, that can be cut to 6 millionths to 8 millionths of a second, Simmons said.
"Bats do 2 to 3 (millionths of a second) relatively easily," Simmons said. "That's the part that's little distressing."

Being able to separate such sounds means the bats could tell the difference between objects just 3/10ths of a millimeter apart -- about the width of a pen line on paper.

In the experiment, the bats were sitting on a platform in a familiar situation, he noted.
They probably don't do as well at night, chasing insects through the trees.  "They seem to be fat and happy all thetime, which means they are intercepting their targets," Simmons observed. "The things they do are shocking."

To succeed in such chases, bats need to be able to differentiate sounds 10 millionths of a second apart, Simmons explained in a telephone interview. "We'd have to do a lot of work to match what they're doing so easily."

While they're still trying to determine why bats are so much better than human technology, they have begun experiments to record bats' brain cell activity as they process sounds.

And Simmons is working on tweaking naval sonars, both in listening for return sounds and in processing that information, to make them a bit more like bats. Dolphins also use sonar, and some have been trained by the Navy to help find mines. But Simmons said it isn't practical to do experiments on dolphins. Working with bats, on the other hand, he hopes to learn ways to improve both underwater sonar and airborne radar.

In Simmons' experiments, the bats are trained to differentiate sounds with large gaps between them, getting a reward of mealworms for each correct decision. Then the timing of the sounds is shortened to test the bats' response.  "They cooperate in these experiments. ... They perform very fast," Simmons said. In an experiment, the bat makes its decision about the sound and then runs forward to get the mealworm. "They don't fly off; they  just sit there and go right to it," he said.

Working with Simmons on the project were Michael Ferragamo, now at Gustavus Adolphus College, and CynthiaMoss, now at the University of Maryland.

• Anomalog: Bats In Elevators
• 604 track _Tommy The Bat_ MP3 by Infected Mushroom off of _The Gathering_ 12"x3 on BNE/Yo Yo/Balloonia/Cosmophilia (1999)

• "tommy the bat" is a takeoff on _Tommy The Cat_ MP3 by Primus.  "say baby do ya wanna lay down by my side...say baby" is sampled, although heavily tweaked.  the original voice is that of Tom Waits
• palindromes
  • "was it a bar or a bat i saw?"
  • "stab nail at ill Italian bats"
• track _Release The Bats_ MP3 by The Birthday Party

• track _Red Bats With Teeth_ MP3 by Angelo Badalementi off of _Soundtrack_ for the film _Lost Highway_ (1997) directed by David Lynch

• indie pop track _Ohio Town Saved From Killer Bees By Hungry Vampire Bats_ MP3 by Jad Fair & Yo La Tengo off of _Strange But True_ on Matador (1998)
• experimental rock track _Bat You'll Fly_ MP3 (160k) by Avey Tare & Panda Bear off of _Spirt They're Gone, Spirit They've Vanished_ on Animal (2000)
• track _Batwings (A Limnal Hymn)_ MP3 (192k) by Coil off of _Musick To Play In The Dark Vol. 2_ on Chalice (2000)
• track _Fruit Bats_ MP3 by Smog off of _Sewn To The Sky_ on Drag City (1995)
• track _Golden Bat Blues Dedd_ MP3 (192k) by Acid Mothers Temple off of _Pataphysical Freak Out MU!_ on PSF #106 (1999)

• entity Aqua Bats - groups with animal names
• track _Deaf As A Bat_ MP3 by The Jesus Lizard
• track _Bat Chain Puller_ MP3  by Captain Beefheart
• Captain Beefheart lives in Mojave, California
• comic book character Batman
  • _Batman Theme_ MP3 covered by Link Wray

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