Naked Science Forum
Life Sciences => Cells, Microbes & Viruses => Topic started by: Paul Anderson on 18/01/2009 10:47:02
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Paul Anderson asked the Naked Scientists:
When a flea jumps, does it know where it is heading for or is it just trying to move anywhere but where it is currently?
If an insect goes up your nose at night, and gets swallowed, before you can blow it out, what are the chances of a pregnant flea being destroyed by your hydrochloric acid in your stomach before it does any damage to you?
On your podcasts you have said that it is the female mosquito which bites. Is it also the female flea that bites?
How do they train fleas for circuses, and which are more trainable, male or female fleas?
If they won't perform, what's the best way to get rid of them without poisoning yourself in the process?
Do some of the remedies such as sprigs of heather work for keeping fleas away, or are they just old wives tales?
What do you think?
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Fleas are trained not to jump by keeping them in a container with a lid. Once trained, they are harnessed by carefully wrapping a thin gold wire around the neck of the flea. Once in the harness the fleas usually stay in it for life. The harnesses are attached to the props and the strong legs of the flea allows them to move objects significantly larger than themselves.
http://en.wikipedia.org/wiki/Flea_circus
Given an adequate supply of food, larvae should pupate and weave a silken cocoon within 1-2 weeks after 3 larval stages. After another week or two the adult flea is fully developed and ready to emerge from the cocoon.
http://en.wikipedia.org/wiki/Flea
I don't think they will do any damage inside your stomach [xx(]
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If an insect goes up your nose at night, and gets swallowed, before you can blow it out, what are the chances of a pregnant flea being destroyed by your hydrochloric acid in your stomach before it does any damage to you?
Depends if the insect you swallowed was a pregnant flea...
Firstly, for the flea itself, I wouldn't back it to survive in your stomach! Fleas just aren't made to survive in that environment and would probably drown in saliva/stomach juices (if it were to make it past your nose hairs in the first place). Hydrochloric acid may help digest a little bit of the flea and gain that tiny extra bit of nutritional goodness, but the flea's thick exoskeleton made of chitin could prevent it from being fully digested.
However, fleas can be the intermediate hosts for some other parasites that can infect humans following ingestion of the infected flea. One of these is the dog tapeworm Dipylidium caninum, which most commonly infects young children but is not particularly harmful, causing mainly an anal itch. The rat tapeworm Hymenolepis diminuta is another (rare) example.
On your podcasts you have said that it is the female mosquito which bites. Is it also the female flea that bites?
Yep, the female flea needs a blood meal from the host so that her ovaries can mature and allow her to reproduce. Just like the mosquito, it is a capillary feeder and injects an anticoagulant into the host to prevent the blood clotting before she can finish her meal. They actually spend most of their lives away from the host, and can survive for several months without needing to feed!
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Anyone know what a flea bite looks like?