thespineanditstingle said: Wait, so what did you actually do to get the pee? What are the pros and cons of each method? Don't leave us hanging!
You write, dear readers, and I listen. There’s been A LOT of interest in the methodology outlined in Things I Learned as a Field Biologist #635. Lamentably, this is not my story to tell: although I’ve collected many bodily excreta/secreta from from many primates, the Strepsirrhini ain’t my game.
However, to satiate the curiosity of the masses I wrote to my good friend Luca Pozzi - whose work is featured in that post and who is currently in Madagascar running some field experiments on the mouse lemurs in question - to ask him for more details!
(Just to visually establish his expertise with the nocturnal beasties, this is Luca. Chilling with a galago. Like a boss.)
I was originally planning on using screen shots of our conversation on WhatsApp for this post, but Luca and I go way back and the conversation can get delightfully salty, so please permit me to paraphrase.
First off: why collect this urine in the first place?
Two reasons: behavioral experiments and chemical analyses. The Strepsirrhini are much more olfactory oriented than our own infraorder within the primates (we belong to the Haplorhini). Especially in the nocturnal strepsirrhines - like the mouse lemurs and galagos that Luca specializes in - urine is used to chemically signal a number of things about the animal who lays down the track. Urine can mediate the sexual functioning of males and females, reproduction, and give sniffers of urine information on relatedness, group membership, and social and sexual status of the urinator. It’s also been proposed to have pheromonal properties! For example, the urine of dominant males has been shown to shut down the reproductive functioning of lower ranking males!
Luca is specifically collecting the urine to test the phylogenetic information it may carry. What that means is that he wants to a) figure out what chemicals are inside it, and b) see if differences in that chemical composition of the urine can be linked to differences in preference for conspecifics vs. heterospecifics (e.g., do they prefer sniffing the urine of another Microcebus murinus to, say, the urine of a closely related species like Microcebus berthae).
Second: Which method works best?
Ok, here’s the deal: Although Luca has tried all of these methods, it’s difficult to say which works best. Here are some thoughts:
1) The Belly Rub method: This one seems ok, but doesn’t work all the time.
2) The Alcohol Method (which is my favorite because it also involves blowing gently on the belly of the mouse lemur once the alcohol is applied, so that it cools while evaporating… and who WOULDN’T want to blow gently on the alcohol-soaked belly of a mouse lemur?!): doesn’t really work well at all, so Luca has scrapped it. Sad face.
3) The Squeeze Method: this one is the money maker. To quote Luca directly:
Most of the times either they pee immediately… (especially one species) or they need some squeezing.
Of course, it’s not all urine and roses:
Unfortunately, most of the times they just don’t pee at all. Or they pee too fast [once they’ve been removed from the trap].
Finally, how is the urine collected, exactly?
I’ll leave this to Luca’s words:
Ideally, directly in a glass tube. Of course, this is almost impossible so sometime I make them pee on a piece of glass and then I pipette the urine with a pasteur pipette in a glass tube. As you can easily imagine everything needs to be glass cause plastic releases lots of compounds that affect chemical properties [of the urine].
Then the samples need to be frozen. We use a -20 [degrees Centigrade freezer], although ideally it should be a -80.
Awesome, Luca. Thank you so much for helping me explain the ‘BECAUSE SCIENCE’ behind that post.
Anything to add for the readers here about working with mouse lemurs in the field?
They are pretty adorable. Except for when they bite you.
If you want to know more about Luca’s awesome work with mouse lemurs and galagos, you can find out more here at:
Or by following him on Twitter at @LPozzi81:
For now, next time you’re in the dark forests of Madagascar, have a mouse lemur in hand, and desperately want to sample their urine, you know exactly what to do:
Squeeze. But squeeze gently. And don’t get bit.
Nota bene: Naturally, all of this squeezing, rubbing, and blowing is approved by the Institutional Animal Care and Use Committees (or similar bodies) of the universities affiliated with Luca’s work, and has been additionally approved by permitting officials in Madagascar and Germany (many permit-granting agencies also require said proof of IACUC approvals before sample collection is allowed).