"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

December 26, 2019

Pollinators for parasites, nosy leeches, and sea lion lice

We've reached the end of yet another year and as usual there have been many interesting parasitology papers published this year, but with so little time to write about them all for this blog, I've had to be a bit picky about which papers to write about.

With that said, what were the parasites and the papers that were featured on the blog this year? Well, let's start under the sea, where parasitic copepods anchor into the flesh of swordfish to drink their blood.  And it's not just the bony fishes that are getting parasitised - among the cartilaginous fishes, this year the blog featured two parasites of rays (also known to some as the flat sharks, or the sea flap-flaps) which get there via shellfish - including a blood fluke that lives in the heart of electric rays and asexually reproduces in clams, and tapeworm larvae lurking in scallops which are waiting to get into the guts of hungry, shellfish-munching rays.

Having a gut full of tapeworms may not sound too pleasant, but it's not as immediately visceral as having parasites up your nose, as one researcher experienced while putting his body (specifically his nose) on the line to find out more about an unusual leech. Leeches are not the only parasites with a fondness for noses, as the nose mites in seals can attest.  And mites are not the only parasites living on sea mammals - this year, a paper was published describing how researchers in Chile came up with an inventive way of sampling lice from sea lions.

Parasites are often armed with some neat evolutionary tricks to help them complete their life cycles, and there were some notable ones which were featured on the blog this year, including a tricky parasitoid wasp that has some special tactics to deal with the elaborate web woven by its spider hosts, a sex-changing parasitic plant which enlist a range of different forest insects to serve as pollinators, and a fluke that makes coral polyps swell and blush.

As always, we also featured some student guest post, with one about lamprey on basking sharks, and one about a type of amoeba on contact lens that you'd want to keep an eye on.

Outside of this blog, earlier this year I was on Australia Radio National talking about parasitic barnacles on sharks and why some lizards are more wormy than others. This has also been the year when I became the social media editor for Journal of Helminthology, so if you are after more parasitology content, follow @JHelminthology on Twitter for tweets about parasitology papers - as presented through parasite memes.

And that does it for 2019, see you all in 2020 for more tales about parasites!