The birds have flown, so the feild work takes a pause for a bit. Now it's time to get into some lab work. My attention is being divided across three main areas: Genetic sexing, feather reflectance measurements and microscope work to examine feather wear. I will get into genetic sexing of red knots soon, they are monomorphic and we need to be able to determine sex from feather samples using PCR. Feather reflectance is a major part of our study, yet we have had all sorts of problems getting our incredibly expensive equipment to work effectively, that's frustrating! So, the most recent work has been on looking at feather wear. Birds moult and replace worn feathers and we are interested in how melanin investment affects the wear and reflectance of the feathers. You can see in this photo below, a relatively new feather and a worn feather.
The wear in this case maps the black outline of the feather - black has different proportions of melanins than the red coloured feather. Our job is to come up with a method that allows us to consistently score the degree of wear. We have spent some time looking at the feathers under 90x magnification, examining barbs and barbules and the wear. Here's some shots- up close and personal.
Above you can see how the barbules have worn off the barbs. Zooming in (though admittedly on a different feather), these look a bit like this... 
and zooming in again...
Who would have guessed there was so much to a feather? Looks aren't everything, are they? Yet for birds they are a lot - camouflage, quality signals, status signals and more. Hmmm...better leave it there, so I don't wear you out.
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