The 2015 Schol Bio paper included a question about a group of birds known as honeycreepers, specifically, the 56 species endemic to the Hawaiian islands. (Or, were endemic: 18, or perhaps 19, are still living; the others are extinct.) Students who’ve already had a look at this paper as part of their preparation for the exam will […]
Continue readingCategory: animal diversity
spiders’ prey and pitcher plants
I’ve learned quite a bit about spiders over the years. (And I have never been able to understand the “burn it with fire!” some folks take towards these 8-legged creatures.) For example, it turns out that some spiders actively hunt fish, while others are vegetarian! Then, late last year, I came across a couple of […]
Continue readingducks, domestication, and selection’s signature
I've always rather liked ducks, ever since we hand-reared some ducklings back when I was still a school-kid. Mind you, the innocent me of those days didn't know what I know now about the effects of sperm competition and sexual selection on their reproductive organs. (Those of an enquiring mind will learn more – much […]
Continue readingcould – & should – the moa be a goer again?
I’m starting to gear up for some Schol Bio preparation days in the regions (hi, Hawkes Bay! See you in 4 weeks!) and realised that I haven’t written anything specifically focused on those exams for a while. So I thought that putting something together would be a good way to spend a rather wet Sunday. […]
Continue readingpoor little pangolins – driven headlong to extinction by human greed & stupidity
Pangolins are strange little creatures, with their diet of ants and termites, and the entire outer surface of their bodies covered with armour-like scales (face, belly & the inner surfaces of the limbs are either hairy or naked). When in danger, pangolins are able to roll up in a ball, presenting only that armoured surface […]
Continue readingthe immortal life of a hydra
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 […]
Continue readingvegetarian 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 […]
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