A new leaf-nosed bat

February 25, 2012 • 12:39 pm

Courtesy of National Geographic, we have a new bat—Griffin ‘s leaf-nosed bat (Hipposideros griffini)—discovered in Vietnam four years ago but only now described in the Journal of Mammalogy. It resembled an already-known species but was distinguished by small differences in morphology, mitochondrial DNA sequence, and frequencies of the echolocation call.

Photograph courtesy Vu Dinh Thon

Leaf-nosed bats are found in both the New and Old World, and the New World ones are the most numerous group in the order Chiroptera (bats), which itself is one of the most diverse order of mammals, second only to rodents (40% of mammal species are rodents; 20% are bats). A probably aprocryphal story relates evolutionist J. B. S. Haldane’s answer when asked what one could infer about the Creator from surveying his creation.  “An inordinate fondness for beetles,” Haldane supposedly said. (Of the roughly 1.7 million described species on Earth, 300,000-400,000 are in the order Coleoptera—beetles.) If that question were asked about mammals, one could reply that God showed an inordinate fondness for rodents and bats, and a notable distaste for primates.

The function of the “leaf” isn’t fully known, but it’s suspected to be important in receiving the echolocation signals emitted by bats.

Here’s Figure 1 from the paper:

Fig. 1. A) Lateral and B) frontal views of ear and nose leaves of Hipposideros griffini, new species (IEBR-T.200809.12, holotype). Not to scale.

You may find this beast ugly, but that’s speciesism!  I find all animals beautiful because they’re products of evolution, embodying all the mechanisms that drive the process. The ugliness, in this case, is probably a byproduct of natural selection.

Bats are often called “flying rodents,” but they’re not even close to rodents.  They are in completely different orders of mammals: Rodentia vs. Chiroptera. Here’s a phylogeny of mammalian groups based on Tree of Life data from the University of Arizona and Berkeley, which clearly shows that humans are more closely related to rodents than rodents are to bats (see also my more comprehensive post on mammalian phylogenies from last October). It’s the weekend, so you can use that bit of information as cocktail-party chat, guaranteed to stop all conversation.

Thong, V. D. et al. 2012. A new species of Hipposideros (Chiroptera: Hipposideridae) from Vietnam. J. Mammalogy 93:1-11.  http://dx.doi.org/10.1644/11-MAMM-A-073.1

30 thoughts on “A new leaf-nosed bat

  1. I always thought that rabbits were rodents. This changes everything! They sure as hell have a rodent-like look about them. Phylogeny can be very counter-intuitive.

    1. Lagomorphs have doubled incisors and the scrotum anterior to the penis, among other differences. But they are rodent-like in many ways, hence the sister-group status and the clade GLires.

  2. Bats are often called “flying rodents,”

    They might be in American English, but I’ve never heard the term in British English. “Flying mice”, yes, but not “flying rodents”.
    The German is, of course, “Fledermäuse”, translating closely to “flying mice”, which is anatomically fairly accurate, if not phylogenetically accurate.

    1. (Then again, I did have family friends who were native German speakers as well as being professional naturalists (technical translators), and a father with some technical German, and a keen amateur naturalist himself ; so possibly my language is not representative.)

  3. Tangentia:

    Cool, and for party trivia, who knew that bats were so close to anteaters, or that shrews were so distant from elephant shrews? Certainly not a biochemist (all taxa look the same after they’ve been thru a Waring blender).

    But re. elephant shrews, one of their lens crystallins is an aldehyde dehydrogenase, one of the many different NAD-binding dehydrogenases of cellular metabolism that have been recruited to serve as structural lens proteins, something that should give pause to creationists using the eye as an example of creation.

    Back to the tree, cool also to see that mice/rats and chipmunks/squirrels are somewhat separated – I’ll show that to a molecular biologist colleague who routinely disdains squirrels as rats with bushy tails.

    And for a final tangential, Swedish for Rodentia is Gnagare (gnawers; the g is pronounced). I like that!

        1. …but then it looks like this placement of bats is poorly supported anyway (light-blue dots).

          It’s worth remembering that all phylogenies are hypotheses, and the nature of the algorithms used often means that the topology of deeper branches is often less certain.

          (But the cocktail-party factoid is still good; the relationship of primates and glires is well supported.)

        2. I see what you mean!

          (Are we not ‘evolving’ to a new use of terms such as “ungulate,” one that refers to useful similarities among taxa that might be due to convergent evolution rather than phylogeny?)

  4. If the structures are indeed for echolocation, that would make sense. To me, they look a lot like the structure you can see if you look inside a cat’s ear. (Protip: Make sure you use a friendly cat!)

  5. Bats are often called “flying rodents,” but they’re not even close to rodents.

    Of course, everybody knows that pigeons are flying rats…

  6. Somebody’s gotta ask: Could it be the leaf nose is not an adaptation, but just caused by a suboptimal mutation that got fixed by genetic drift?

    1. what about the millions of generations of natural selection to which the structure has been exposed since its origin?

  7. “I find all animals beautiful because they’re products of evolution, embodying all the mechanisms that drive the process. The ugliness, in this case, is probably a byproduct of natural selection.”

    What double-think is this?

  8. What I found striking is that rodents are more closely related to us than to bats.

    If anyone is interested in a great and entertaining description of how humans relate to other life on earth, you can’t go past Richard Dawkin’s excellent ‘The Ancestor’s Tale’.

  9. Three quibbles about the tree depicted:
    1. it doesn’t distinguish between well-supported and largely hypothetical branches.
    2. there’s only one aardvark.
    3. why are tree-squirrels and marmots subsumed under “chipmunks”? Also, a large proportion of mammalian diversity is found under ‘mice/rats/beavers’ here.

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