Bat species found to have tongue pump to pull in nectar

Bat species found to have tongue pump to pull in nectar
The pumping tongue nectar-feeding bat Lonchophylla robusta visiting a bromeliad flower. Credit: M. Tschapka/University of Ulm

(Phys.org)—A trio of researchers affiliated with the University of Ulm in Germany and the Smithsonian Tropical Research Institute in Panama has found that one species of bat has a method of collecting nectar that has never been seen before in any other animal. In their paper published in the journal Science Advances, the team describes how they discovered the unique eating method using high speed cameras, and their theories on how it works.

Scientists have seen many examples of animals that lap up liquid in many different ways, they have also seen examples of animals that are able to suck water right out of a river, but until now, there has never been a documented sighting of a an animal that is able to pull a liquid against gravity, using a pumping-mechanism.

Intrigued as to how Costa Rican Orange Nectar Bats pull nectar from plants, the team set up a next to a with a clear liquid meant to serve as nectar and recorded several of them in action. In studying the video, the researchers discovered that the bat lowered its tongue into the liquid and then simply held it there while the liquid miraculously made its way up the tongue and into the mouth. Closer examination showed that the tongue had two grooves (which were open to the air) along its length and that tiny muscles appeared to be undulating along the sides of the groves as the liquid was pulled up—serving as a pumping mechanism of some sort.

Tongue of Lonchophylla. robusta at near-maximum extension (detail, lateral view). Credit: Tschapka, Gonzalez-Terrazas, Knörnschild Sci. Adv. 2015;1:e1500525

The researchers cannot say for sure what is going on, but suspect two forces are at work: and . They believe it is likely the liquid is held in the grooves by capillary action, and that the tiny muscles somehow force the to move upwards, against gravity—sort of like allowing one end of a sponge to rest in water while continuously wringing out the water that is pulled into other parts. The result is an odd, unique and efficient means for drawing nectar from a flower. They note that the unique physiology of the mouth suggests that the bats evolved their way of eating independently of other species.

Author Marco Tschapka describes the unusual way some bats use their tongues to obtain nectar. Credit: AAAS/ Carla Schaffer

Explore further

Hummingbird tongues are tiny pumps that spring open to draw in nectar

More information: Nectar uptake in bats using a pumping-tongue mechanism, Science Advances  25 Sep 2015: Vol. 1, no. 8, e1500525, DOI: 10.1126/sciadv.1500525

Abstract
Many insects use nectar as their principal diet and have mouthparts specialized in nectarivory, whereas most nectar-feeding vertebrates are opportunistic users of floral resources and only a few species show distinct morphological specializations. Specialized nectar-feeding bats extract nectar from flowers using elongated tongues that correspond to two vastly different morphologies: Most species have tongues with hair-like papillae, whereas one group has almost hairless tongues that show distinct lateral grooves. Recent molecular data indicate a convergent evolution of groove- and hair-tongued bat clades into the nectar-feeding niche. Using high-speed video recordings on experimental feeders, we show distinctly divergent nectar-feeding behavior in clades. Grooved tongues are held in contact with nectar for the entire duration of visit as nectar is pumped into the mouths of hovering bats, whereas hairy tongues are used in conventional sinusoidal lapping movements. Bats with grooved tongues use a specific fluid uptake mechanism not known from any other mammal. Nectar rises in semiopen lateral grooves, probably driven by a combination of tongue deformation and capillary action. Extraction efficiency declined for both tongue types with a similar slope toward deeper nectar levels. Our results highlight a novel drinking mechanism in mammals and raise further questions on fluid mechanics and ecological niche partitioning.

Journal information: Science Advances

© 2015 Phys.org

Citation: Bat species found to have tongue pump to pull in nectar (2015, September 28) retrieved 23 August 2019 from https://phys.org/news/2015-09-species-tongue-nectar.html
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Sep 28, 2015
"a method of collecting nectar that has never been seen before in any other animal..."

-Sure it has
http://cdn0.daily...en_3.gif

Sep 28, 2015
Sounds the same as the Hummingbirds

Sep 29, 2015
References?

As far as I know hummingbirds lick up liquids, as most animals do. I don't think those bat researchers would have missed anything in published literature when they needed to make such a broad claim.

Sep 30, 2015
They also eat a lot more insects than people appreciate.

I had a girl friend once that I think must have been part bat.

Sep 30, 2015
TheGhostofOtto1923

1 /5 (3) Sep 28, 2015
"a method of collecting nectar that has never been seen before in any other animal..."

-Sure it has
http://cdn0.daily...en_3.gif
kelman66

1 /5 (2) Sep 28, 2015
Sounds the same as the Hummingbirds


Ah, an insight into the site's trolling problem. The infinitely perplexing "can't google" troll. This is a person that will proclaim a fact as if it were 2+2 without ever checking on it, as a data oriented person would simply because it's the polite thing to do. They are the opposite of the Kiersey "data seeking personality". My theory is that they had parents that were ignorant blow-hards and never learned "data protocol" communication.

GOO brains is the worst. If Otto states a fact, you can put good money on the opposite every time. His links are a good example that this is a real developmental disorder. He tries to use data, but it's like a chimp with a typewriter. And I'm not waiting for Shakespeare.

Sep 30, 2015
That's a valuable insight, JLJ. It would explain why Otto comes across like a deaf-mute trying to rap hip hop.

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