Category Archives: Education

Infestation of camel crickets

When it’s too hot to take photographs outside, I can always go down to my basement to photograph camel crickets (“sprickets” to many). I know, lucky me. But if you have a moist basement, you probably have them, too. The ones below are the introduced species (I think), Diestrammena asynamora, from Asia. They drive me nuts. So much so that I wasted time collecting ways to get rid of them (see my page, “Getting rid of camel crickets“, if you’re interested). The list is not 100% effective, as photographs attest, but at least I don’t have thousands of them anymore.

Colin Purrington Photography: Insects &emdash; Camel cricket (Diestrammena asynamora)

Colin Purrington Photography: Insects &emdash; Camel cricket (Diestrammena asynamora)

Colin Purrington Photography: Insects &emdash; Camel cricket (Diestrammena asynamora)

Colin Purrington Photography: Insects &emdash; Camel cricket (Diestrammena asynamora)

Colin Purrington Photography: Insects &emdash; Camel cricket (Diestrammena asynamora)

Colin Purrington Photography: Insects &emdash; Camel cricket (Diestrammena asynamora)

Colin Purrington Photography: Insects &emdash; Camel cricket (Diestrammena asynamora)

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Distinguishing tobacco and tomato hornworm caterpillars

After agonizing over the identification of hornworm larvae for years, I’ve developed two tricks that I’d like to share. Tobacco hornworm (Manduca sexta) caterpillars have stripes (seven of them), so remember that by thinking of Lucky Strikes cigarettes. Horn is usually red or red-tipped, like a cigarette. Also, tobacco gives you dark teeth and lungs … and tobacco hornworms have black shadows on their stripes. Tomato hornworms (Manduca quinquemaculata) have eight chevrons (Vs), which you can remember by thinking of V8 juice, which is primarily tomato juice. Here’s the graphic you can share with friends who might have it wrong:

Photographs of tobacco and tomato hornworm caterpillars

If you can, please spread the word … most of the tens of thousands of tobacco hornworm photographs on the internet are misidentified as tomato hornworms. Even Wikipedia page for tomato hornworm shows tobacco hornworm larvae (I’m working on it …). The problem is that tobacco hornworm eats tomatoes, and people with fancy cameras grow a lot of tomatoes.

For people living in Hawaii, please note that the above doesn’t include Manduca blackburni, which is closely related to tomato hornworm.

Photograph of tomato hornworm from Amanda Hill.

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It is not the strongest of the species that survives

“It is not the strongest of the species that survives, nor the most intelligent, but the one most adaptable to change.”

From Charles Darwin Foundation gift shopThis quote (and hundreds of mutant kin) is often attributed to the naturalist Charles Darwin, but he said no such thing (see a recent post on the true source). The mistake is everywhere: in coffee table books, in natural history museums, and even in the gift shop of the Charles Darwin Foundation (photo shown here is from their Twitter feed — click to enlarge).

It is not the strongest of the species that survives, nor the most intelligent, but the ones most adaptable to change Charles DarwinThis misattribution is, of course, annoying to people who admire Charles Darwin and his actual writing (he wrote ~25 books, and thousands of letters). So to fight this, I thought I’d make a few slides that might eventually get included in Google search results, and thus available to people who want to use the quote in their business management slide decks. I made three versions. Please use these slides if you are able. Share them on Twitter. Etc. Every bit helps.

It is not the strongest of the species that survivesThe first version features a marine iguana with its mouth open, as if it was saying something. Darwin and others described these beasts as stupid looking, but the species are adapted to the islands in a rather spectacular way  — individuals evolved to swim underwater and eat algae — so it’s a rather good image to use for the quote. The second is a photograph of Charles Darwin, perfect for people who like the quote but really need a photograph of the chap who clearly inspired Megginson. The third slide is a photograph of Leon C. Megginson himself. He was a professor of business management in Louisiana. Download any of the slides by clicking on the thumbnails, then save.

It is not the strongest species that surviveAs proof of why we need to get the word out, please see Twitter feed below, updated to show recent Tweets that contain the quote. The phrase is especially adored by nutritionist bloggers, consultants, and business folks who spew inspirational quotes. It would be great if those quotes credited Dr Megginson.

And here’s a quote I dreamed up to explain what is going on:

“It is not the strongest of the sentences that survives, nor the most intelligent, but the one that sounds most like Darwin.”

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I was asked on Twitter if I could clarify my views on text justification for conference posters, but decided I couldn’t come up with a good 140 character response. So here you go:

fabric-postersI recommend left-justified research posters for several reasons. First, I read in some typography/readability article (can’t find reference but will keep looking) that your brain subconsciously uses the ragged right edge to better gauge vertical reading position, allowing reader to more quickly travel through a paragraph. This matters less if you have good space between lines of text, but matters a lot if you’ve squished lines together to fit more on your poster (unfortunately, a very common scenario). Second, left-justified text has more predictable spaces within and between words, and that consistency makes sentences easier (faster) to read. Fully justified text can be especially awful when column widths are too small, and for smaller text boxes like figure and table legends. As an example of how awful those space problems can be, here’s an artificial dem on stration. These spacing issues are much bigger problems for people with dyslexia (20% of people, perhaps) and other reading disorders. That said, typesetting software such as InDesign have really good controls for minimizing the spacing problems of fully justified text. And some fonts (often the ones you have to actually purchase) are good at spacing themselves. Third, left-justified paragraphs suffer much less from the rivers and pigeonholes of white space that are sometimes created by full justification. These distracting visual elements are probably more of a problem for people or disciplines that are fond of big words, which coincidentally are those that love to have poster sessions. You can minimize rivers and pigeonholes by turning on automatic hyphenation, of course. In related news, Powerpoint doesn’t do auto-hyphenation, which makes it terrible for posters because you typically want to cram as much on a page as possible. Finally, errors in spaces between sentences (you just need one) are much easier to catch if you are using left justification.

But there are at least two reasons why you might reasonably ignore what I’ve written above. First, full justification looks so cool! If you want people to think you’re cool and professional, and you probably do, you might just go ahead and hit that button … because most viewers (and mentors, and poster judges) will also be similarly impressed. Unless they’re dyslexic, in which case they might hate you. A compounding problem is that justification looks cooler and cooler as you reduce font size … contributing to the word problem that plagues almost all conference posters. Second, there seems to be some research (again, I’m looking for citations I know I have somewhere) suggesting that full justification might increase a reader’s comprehension of the text. My guess is comprehension increases because one reads it more slowly. Changing the font every sentence might also increase comprehension in the same way, though I don’t recommend doing that. (Hyphenated paragraphs take longer to read, too.)

By the way, don’t center-justify text in figure legends and table captions. Many prestigious journals use centered text in this way, but I think they’d change to left justification if they could do so without admitting to prior foolishness.

As an aside, I recently purchased a Kobo eReader because I can specify left-justification. I couldn’t do that with my Kindle. I can also now read while floating in a pool (my Kobo is waterproof).

If for some reason the above didn’t bore you, please see more of the same at Designing conference posters. Drop me a note if you have actual data for any of the above speculation.

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Red milkweed beetles

Mating pairs of red milkweed beetles (Tetraopes tetrophthalmus) are not rare (they can couple for hours at a time), but I thought this couple looked cute, in a worried sort of way. The half-lidded expression is because their compound eyes are bisected by their antennae. Beautiful beetles.

Colin Purrington Photography: Insects &emdash; Red milkweed beetles (Tetraopes tetrophthalmus)

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