Facts Of Life On Planet Parasite

We've come to the end of yet another year and all that it entails in the field of parasitology. As with last year, we have continued to the feature guest posts by student from the University of New England ZOOL329/529 class of 2014, who wrote about fungus that kills water bears, midges that suck blood from mosquitoes, and wasps that zombifies cockroaches and many more. In addition to student guest posts, there were some conference coverage (Part 1, Part 2) mixed in as well.

As for some of the parasites that were featured this year, we looked under the sea - and found that it was filled with shark-suckers, face-huggers, brood-blockers, and egg-mimics. While they sound like the monsters of science fiction horror, but they are non-fiction of the real world, and they are not monsters, but simply living things trying to get on with their life - admittedly in ways that somewhat terrifies us.

This year, we learned about parasite that can take a reproductive toll on their host, such as a lovecraftian parasitic copepods that infect flamboyant sea slugs, a peculiar barnacle which sticks itself in the flesh of a shark and can castrate its host, a tiny crab that brood-blocks its limpet host, and a copepod that masquerading as a lobster egg so they can feast on the brood of its host.

When they're not killing their hosts' broods one way or the other, they outright disintegrate them. We learn about the parasite that kills a species of "killer shrimp" by dissolving them into shrimp paste, but not before causing the crustacean to bring themselves out into the open to the waiting maw of its cannibalistic cousins. Other parasites like myxozoans do not kill their host outright, but when their fish hosts do die, it cause their flesh melt into mush, much to the dismay of fishermen.

But it's not just aquatic critters that are the target of parasites - they rumble in the jungle too, and are found in larger terrestrial animals like rhinos and monkeys, as well as smaller ones like crickets. In the case of the cricket, some parasites actually bring their terrestrial host into the aquatic realm by manipulating the host's behaviour. Other parasites mess with their host's sense of smell. And some parasites don't alter behaviour directly but just gets in the way - the worm that gets in the eyes of prairie chickens (and other birds), and fish are not faring any better, with a parasite that literally get all up in their face.

And there is no escape from parasitism - parasites are found everywhere, even in deep sea hydrothermal vents. And they do more than just gross us out or cause their host to suffer - they can also cause changes in their hosts that sends a ripple effect into the surrounding ecosystem too. Parasites are ubiquitous, diverse, and a major components of this planet's biological diversity. Parasitism is as much a fact of life as feeding, fighting, and f…reproducing - that is unless a parasite gets in the way of your ability to do that last thing…

We will back next year to bring you more posts on parasite research which you might not have read about elsewhere - so here's to another year of more parasitology science! Bring on 2015!

P.S. If you can't wait until next year for your parasite fix, you can check out some of my other parasite-related writing on The Conversation on the important ecosystem roles played by some parasites here and on parasites that blind their hosts here. As well as writing this blog, I have also been doing a regular radio segment call "Creepy but Curious" where I talk about parasitic (and non-parasitic organisms) like hairworms, emerald jewel wasps, killer sponges, vampire snails, colossal squids, second-hand vampires, and melting seastars. You can find links to all these and more on this page here.