"So, naturalists observe, a flea has smaller fleas that on him prey; and these have smaller still to bite ’em; and so proceed ad infinitum."
- Jonathan Swift

October 31, 2010

October 31 - Desmodus rotundus

The common vampire bat, Desmodus rotundus, seemed like a good parasite to feature on Halloween. These mammals derive all of their nutrition from the blood of other mammals, usually cattle, but sometimes other livestock and even sleeping humans. They sneak up on their hosts using a very quiet hopping motion and then slice open the skin with razor-sharp teeth, lapping up the blood that spills out. Vampire bats can only survive a few days without feeding, but have evolved a social behavior known as reciprocal altruism where a bat that feeds successfully one night may regurgitate some of its meal to a hungry roostmate. Later, the recipient may be the lucky one and return the favor to this donor. Vampire bats can be found in many places throughout the neotropics, but have sometimes been subjects of eradication campaigns because of the fear of rabies that they can spread.

16 comments:

  1. Good to change the paradigm for this creature.

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  2. susan,what is the scientific definition of a parasite?

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  3. Isn't parasite. But very cute.

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  4. This comment has been removed by the author.

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  5. Just the opposite. Not cute, but I definitely consider this a parasite.

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  6. Maybe I missed something because of the language barrier, but I don't think that this bat lives constantly in/on any organism... does it? Do you consider a mosquito female a parasite as well? Please, correct me if I'm mistaken.
    And I really think it's cute, so furry and tiny... :)

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  7. Perfect for Halloween! I also consider Desmodus rotundus to be a parasite. Check out these links: vampire bats walking and running:
    http://vimeo.com/3772107
    http://vimeo.com/3772117

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  8. I try to define "parasite" as broadly as I can - especially in this blog, where my goal is to highlight biodiversity. So, I consider parasites to be those things that derive their nutritional benefit solely from another organism, without consuming it entirely, like a predator would. A lot of parasites don't live in or on their hosts constantly - I don't like to use time in that sense as a limitation.

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  9. interesting definition.
    it made me wonder,a fetus can be also considered as a parasite. it feeds on the mom!

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  10. Well, many pregnant women do make that joke! I think that two important components to the definition have to do with the fact that the two interacting organisms are different species and there is also usually a difference in size - the smaller thing is feeding off the larger thing.

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  11. But the official scientific definition of the word "parasite" still includes the fact that the parasite (or at least one stage of it) lives on the surface or inside of the another organism. And this is not individual; it's a definition.
    Most of living organisms are parasites. The number of them is incredible. I don't think there's any problem with their diversity.

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  12. The world is not always so neatly compartmentalized. I am trying to be inclusive. But, you're right - the number is incredible -just wait until the end of the year!

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  13. I agree with Susan- there are many parasites (fleas, ticks, bedbugs) that spend a great amount of time (sometimes months) away from their hosts. There are even worms like Strongyloides with free-living stages in their life cycles. Restricting parasites to organisms that live on or in the host is way too narrow a definition.

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  14. also,i might add, chiggers and leeches are parasites that bite the host and then get off him.
    they are still parasites.

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  15. As someone who has studied leeches and seen many a leech talk at the American Society of Parasitologists meetings, I wholeheartedly agree!

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  16. And so do lions and tigers bite and eat other animals. Parasites?

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