World's Longest Tongue*

Henry Fountain described the magnificent tongue of the Andean bat Anoura fistulata in a story that appeared in the December 19, 2006 New York Times Science section.

Long story (and tongue) short: The bat's tongue (above, unfurled to imbibe from a test tube filled with sugar water and below, taking nectar from a flower) is one and a half times its body length.

The article follows.

For an Andean Nectar Feeder, a Tongue That Wags the Bat

Imagine your tongue was nine feet long.

That’s about how long it would be if you were a certain kind of nectar-feeding bat.

The bat, Anoura fistulata, found in the Ecuadorean Andes, has a tongue one and a half times its body length. For the 2-inch plus bat, that comes out to a 3.3-inch tongue. Proportionally, this is the longest tongue of any mammal, and the second longest (next to the chameleon) among vertebrates.

Most nectar-feeding bats have long, slim tongues, the better to reach the sweet liquid contained in the flowers they pollinate. But Nathan Muchhala, a University of Miami doctoral student who has studied these bats, known as glossophagines, said he noticed something different about A. fistulata, which he first described as a new species last year.

“Its tongue seemed longer — about twice as long,” he said. “At that point I knew something was up.” A report on the record tongue was published in the journal Nature.

Glossophagines have a retractor muscle in the chest, but the tongue itself (which is pumped full of blood to extend it) begins at the base of the oral cavity. A. fistulata, however, keeps the actual tongue in its chest: it begins between the heart and sternum.

Mr. Muchhala wondered why this particular bat’s tongue was so long, and found the answer in his earlier studies in the Andes of the types of flowers that these and other nectar-feeding bats were visiting. He remembered a particular flower, Centropogon nigricans, with a nectar-containing neck, called a corolla, that is the same length as the tongue.

“Once I found out the tongue was so long, I started to connect it to that,” he said.

Studies of this and other bats showed that while they all carried pollen from many flower species, only A. fistulata was carrying this pollen from C. nigricans. And the flower was found only within the bat’s range on the western slopes of the Andes. All of this points to the possibility that the bat’s tongue and the flower evolved together.

“It’s still a little dicey issue,” Mr. Muchhala said. “I can’t really prove it.” But it seems a likely explanation for the similar length of tongue and corolla.

Brock Fenton, a bat specialist at the University of Western Ontario who was not involved in the research, said the long tongue was “an astonishing adaptation,” but not totally surprising given what scientists are learning about bats.

“We’re going to end up with more and more examples of this kind of specialization,” he said.

....................

More?

Here's a link to the abstract of the Nature article, which follows.

Nectar bat stows huge tongue in its rib cage

Bats of the subfamily Glossophaginae (family Phyllostomidae) are arguably the most specialized of mammalian nectarivores, and hundreds of neotropical plants rely on them for pollination. But flowers pollinated by bats are not known to specialize for bat subgroups (unlike flowers that have adapted to the length and curvature of hummingbird bills, for example), possibly because the mouthparts of bats do not vary much compared with the bills of birds or the probosces of insects. Here I report a spectacular exception: a recently-described nectar bat that can extend its tongue twice as far as those of related bats and is the sole pollinator of a plant with corolla tubes of matching length.

.....................

*Proportionally