July 16, 2011

Spiders sniff out humans

This is a jumping spider, and it is unusual in more ways than just its looks.

Join Our Community of Science Lovers!

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American

This is a jumping spider, and it is unusual in more ways than just its looks.

The jumping spider, Evarcha culicivora, or the ‘vampire spider’ is the only animal which chooses its prey based on what the latter has just eaten: it attacks mosquitoes that have recently sucked blood, rather than other types of food.¹

New findings have made this awesome creature that little bit more exciting. Scientists have known for a while that this spider has excellent eyesight. Now they have discovered that this spider can smell the odour of humansinside the mosquitoes, just as mosquitoes can smell us.²

On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

The scientists took some dirty socks (I kid you not) and blew the smell of them towards a spider held in a chamber. They also did the same thing but using clean socks. Spiders which had the dirty-sock smell wafted towards them stayed in the chamber longer than the ones that had the clean-sock smell.

This is the first spider found to be able to smell out humans. What’s more, the favourite mosquito snack of this spider is Anopheles, the mosquito which is a vector for malaria. Just as Anopheles mosquitoes use human smell to sniff out their blood meal, so this spider is using the smell to sniff out the mosquitoes.

This is probably a little bit out there, but I’m envisioning a scene where we release a whole load of these mosquito-sniffing machines out into the worst Malaria-inflicted areas of Africa…?

¹Jackson, R.R., Nelson, X.J., and Sune, G.O. (2005). A spider that feeds indirectly on vertebrate blood by choosing female mosquitoes as prey. Proc. Natl. Acad. Sci. U. S. A. 102, 15155.

²Cross, F.R., and Jackson, R.R. (2011). Olfaction-based anthropophily in a mosquito-specialist predator. Biol. Lett. doi:10.1098/rsbl.2010.1233

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American