Category Archives: Education

Bee and wasp hotels on iNaturalist

If you’re fond of hole-nesting bees and wasps, please join the new “Bee and Wasp Hotels” project on iNaturalist.org to document the guests and hangerson that arrive at your hotel. Below are 20 of the most recent observations:

Currently the most photographed visitor is the four-toothed mason wasp (Monobia quadridens). But also plenty of mason bees as well as parasites looking for mason bees. There has also been a slug sighting (don’t ask). 

If this sounds fun but you don’t have a hotel, here are my thoughts on building one.

Shaving your legs to deter ticks

Girl with shaven legs

People shave their legs for a variety of reasons: to look younger, to look less like men, to show off tattoos, to show off muscle definition, to improve athletic performance (less drag, plus fools brain into thinking you’re going fast), to facilitate post-accident wound cleaning (cyclists), and because shaved legs induces a pleasurable sensory overload (at least to some). But can shaving also protect you from ticks? I became curious this week after watching a tick crawl up my leg:

Male American dog tick (Dermacentor variabilis) crawling on human leg.

No experiments on this topic have been done, but I found three relevant snippets on the internet:

“One thing that helps is shaving your legs. Not a foolproof way but I would say it reduces them critters by 80%, maybe more. I noticed that when my wife and I were out and she had none, I had around 14 that day.” source

“As an experiment I shaved my legs before riding point to point at lbl with KRS and a few others. It was tick season. After 40+ miles of riding I had 1 tick on my sock. Along the way KRS pulled OVER 15 ticks. We rode the same route at the same pace. I’ve kept the hair off ever since.”  source

“I’d say its mostly impractical. Although, I know many trail runners (including myself sometimes in the summer) do it to prevent ticks from attaching.” source

It makes sense that shaving would deter ticks. The first is obvious: ticks can grip hair, so if you are hairless (and are wearing shorts, skirt, or kilt), they can’t climb as fast. The second is that you if you have hairless legs you can most likely better feel them crawling up your leg. I.e., all eight of their legs are touching your skin’s sensory array. The third is that when you remove all your leg hair you are removing a lot of sensory distractions caused by wind (experiment on swimmers) and thus you can zero in on things crawling on you. Indeed, all of these mechanisms might touch on why we evolved to be relatively hairless in the first place.

One experiment that needs to be done is to count the numbers of ticks on a group of people out for a walk, some of whom shave. But at least in the United States, that would break down to men versus women, and males smell worse than women and thus might attract more ticks, regardless of hirsuteness. And men are usually larger, so there’s the surface area thing that goes against us, too. So it would be far better to recruit a group of hairy-legged people and ask them to shave just one leg, then march around a field known to have ticks. An ideal group for this experiment might be a men’s swim team right before the season begins. I.e., they all have hairy legs but will likely shave them for the season … so they won’t care. Would be crazy photogenic and a great way to strengthen bonds between campus coaches and faculty. Plus great team-building exercise. Would get the college on the evening news I’m sure.

A simpler design might be to just have a motivated group of people (perhaps students in a field ecology course?) conduct tick races on shaved, unshaved legs. You just need to start them on the ankles and have participants hold still while the ticks make their ascents. That would be equally photogenic and fun, I think.

If somebody does go ahead and conducts this experiment — and if the effect is huge (my guess) — the next step would be to alert the folks at the CDC so they could add a shaving recommendation to their tick page. The reaction to that would be entertaining.

Male American dog tick (Dermacentor variabilis) crawling on human leg.

Conference poster full of tips for creating conference posters

In case you need a quick guide to making a conference poster, here are two versions of my poster of poster tips. Just view them large, or display with a room projector and invite students to come up and read together. More details below the images.

Poster example (Colin Purrington's)
Advice on designing scientific posters

Both posters are descendants of a document I created circa 1997 for my evolution students at Swarthmore College. The bottom one is available as a PDF if you want to print an actual poster of it — which I highly recommend if you are assigning a poster project for your class.

My full tips are at Designing conference posters. I created the website for my students, too, but eventually made it public in case it might help make the world’s poster sessions more enjoyable.