Students often get to look at hydras – tiny, fresh-water members of the group that includes sea anemones, jellyfish, corals, and the Portuguese man’o’war. All these cnidarians have a simple body-plan: two layers of true tissue with a jelly-like layer between them, a sac-like gut with a single opening that acts as both mouth and […]
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vegetarian spiders? what is the world coming to?
Like probably everyone reading this, I have always thought that spiders are carnivorous, sucking the precious bodily fluidsA from their prey. I mean, those fangs! And I was wrong, for it seems that some spiders eat some plant material alongside their liquid meals – and some are almost fully vegetarian. A just-published paper (Painting, Nicholson, […]
Continue readingleech ‘therapy’ redux
Back in 2012 the Herald ran a series on alternative 'therapies' that included a somewhat uncritical piece on the use of leeches – the practitioner concerned claimed, for example, that they could be used to 'treat' diabetes. I blogged on this back then, as did fellow Sciblogger Siouxsie Wiles, & the criticisms we made then still stand. […]
Continue readingmelibe engeli – the strangest thing i’ve seen in ages
I mean, really – have you ever seen something like this before? Melibe engeli is a type of sea slug, and a most unusual one. Its body is partly translucent, and has projections called cerata, themselves covered with smaller projections called papillae, down both sides. The animal is an active hunter – but what a […]
Continue readingselection and dog breeds
So, I own a pocket wolf. … … Oh, OK, I own a little black mini-poodle. But, like all dogs, he has the same number of chromosomes as a wolf! There've been several articles posted recently about the evolution of domestic dogs. While we've tended to think that domestication didn't begin until humans began to […]
Continue readingrun! well, amble! the giant carnivorous snails are coming!
There’s a lovely, life-size bronze sculpture of a Powelliphanta land snail sitting on my china cabinet. I love it because a friend made it for us – and because snails in this genus are rather special, for they are all carnivorous. Now, I ‘knew’ this fact, but I’d never actually seen one feeding. Snails being normally rather […]
Continue readingattack of the zombie snails
The semester's begun, teaching has started, admin isn't letting up any time soon, & there are days when I feel like a zombie by home-time. So it seems entirely appropriate to revivify a post I wrote 3 years ago, on that very subject. Honestly, sometimes I think the zombie apocalypse is already here. Certainly zombies […]
Continue readingtunicates – apparent simplicity belies a complex past
Tunicates are more commonly known as 'sea squirts' – little blobby marine creatures that squirt water when you touch them (hence the name). We don't hear about them often, except perhaps when they make the news for all the wrong reasons. But from an evolutionary perspective they are fascinating little creatures – and it's largely […]
Continue readinghow do hedgehogs mate, and other sensitive questions of that ilk
So, last night I was asked how hedgehogs mate. The obvious answer was, carefully! My interlocutor suggested that perhaps face-to-face was most likely, but as far as I know, very few species (& that short list includes our own) do that. It turns out that care is indeed needed, for the male approaches the female […]
Continue readingthey wander our faces at night – and procreate in our eyelashes
Demodex mites are tiny little creatures that live in mammals’ hair follicles. I first heard about them years ago, when I watched a documentary with my science class back at PN Girls’ High. It was about animals that are parasitic on humans, and after the segment on eyelash mites, I don’t know about the girls […]
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