Nerd of this parish.
Aug 26
![Coin distribution overlaps for increasing sample size [CC-BY-SA-3.0 Steve Cook]](https://www.polypompholyx.com/wp-content/uploads/2015/08/coin_overlap_for_different_sample_sizes-300x300.png)
In a recent(ish) post, we saw that if a fair coin is flipped 30 times, the probability it will give us 10 or fewer heads is less than 5% (4.937% to be pointlessly precise). Fisher quantified this using the p value of a data set: the probability of obtaining data (or a test statistic based on those data) at …
Aug 23
![Acanthus mollis [CC-BY-SA-3.0 Steve Cook]](https://www.polypompholyx.com/wp-content/uploads/2015/08/Acanthus_mollis-225x300.jpg)
Plants can have some very odd names. Bears are not renowned for their trousers, and this spiky sod is the last thing anyone would want to make a pair of trousers from, but “bear’s breeches” it is. Even its Latin name is odd: acanthus means spiny, and mollis means smooth; a literal oxymoron. It might not look very familiar, but it may be the …
Aug 17
![Bucephalus minimus [CC-BY-SA-3.0 Steve Cook]](https://www.polypompholyx.com/wp-content/uploads/2015/08/Bucephalus_minimus-260x300.jpg)
This is another of the things we have found down a microscope in one of our undergraduate practicals, but for once it’s not a ciliate. This is the larva of a parasitic fluke called Bucephalus, which is the Greek for ‘bull headed’. It’s appropriate for this fluke not because it looks like Alexander the Great’s horse, but because …
Aug 10
![A graph to show [CC-BY-SA-3.0 Steve Cook]](https://www.polypompholyx.com/wp-content/uploads/2014/12/a_graph_to_show-300x145.png)
I’ve never been sure where “a graph to show…” comes from. As far as I can tell, A-level specifications don’t use or specify this wording, and you wouldn’t typically see it in a figure legend in a scientific paper. But if you ask first-year students to put a title on a graph without any further guidance, almost every one of them will default …
Aug 10
![Flea from Hooke's Micrographia [Public Domain: Steve Cook]](https://www.polypompholyx.com/wp-content/uploads/2015/08/micrographia_flea-300x225.jpg)
For three centuries, the Black Death was routinely epidemic in London. The first outbreak – in 1348 – probably killed half the population of England; the last outbreak – from 1665 to 1666 – probably killed a quarter of the population of London. In 1665, Isleworth was a small village several hours’ walk (or row) from …
Aug 03
![Orobanche minor [CC-BY-SA-3.0 Rosser1954]](https://www.polypompholyx.com/wp-content/uploads/2015/08/Orobanche_minor-225x300.jpg)
My annual summer ritual to stave off death for one more year involves running round Kensington Gardens and Hyde Park, which are situated conveniently close to $WORK. I lumbered merry as a shroud. That aches and sweats o’er trails and heights, When all at once I saw a crowd, A host, of golden parasites: Yellow rattle is a member of the broomrape family, which …
Jul 10
![Phage vs. host [CC-BY-SA-4.0 Steve Cook]](https://www.polypompholyx.com/wp-content/uploads/2015/07/phage_vs_host-300x207.png)
For a recent schools’ outreach day, I put together a card-game based around the arms-races that develop between bacterial hosts and their viruses (bacteriophages). It’s mostly just a bit of fun, but if anyone finds it useful or can suggest improvements (or just make them! I release this under a CC-BY-SA-4.0 license) I’d be happy to hear them.
Dec 16
![Stentor sp. [CC-BY-SA-3.0 Steve Cook]](https://www.polypompholyx.com/wp-content/uploads/2014/12/Stentor_sp.-244x300.jpg)
We had the annual “looking at muck down a microscope” practical last week. As usual, the best thing we saw was a ciliate in some pond water, in this case a little trumpet animalcule: Previous winners: Vorticella and Lacrymaria. The Ciliata really are the phylum that keeps on giving.
Dec 15
Well, at least 2:8 is plausible. 2:1 And it came to pass 10 years after the death of Herod the Great, that there went out a decree from Caesar Augustus that all the world – except those irrelevant bits that the Romans hadn’t conquered – should be taxed. 2:2 (And this taxing was first made when Quirinius …
Jul 02
![Urtica dioica trichomes [CC-BY-SA-3.0 Frank Vincentz]](https://www.polypompholyx.com/wp-content/uploads/2014/07/Urtica_dioica_trichomes-300x262.jpg)
Nettles have a rather unhappy reputation as bringer of painful welts, and – at this time of year – dribbling noses too. The welts are probably caused by histamine, and the pain by oxalic and tartaric acids, which the nettle injects into your skin through the tiny brittle hairs that cover its stems and leaves. If …