They have just completed the first half-semester experiment, a complementation test with two loci in flies, and we sat down in lab and did an analysis of the data. Perfect execution! We got the expected result (the genes complemented each other) and all of the students are now officially masters of basic fly breeding.
Then, just because the F1s from that cross were all heterozygotes at two loci, we went ahead and did another cross with them, your classic dihybrid cross, which should result in 4 phenotypes with a ratio of 9:3:3:1, according to that old guy Mendel. It did! It’s always thrilling to do these simple experiments that we all take for granted and see that, by god, Mendelian genetics actually does work under these specific conditions, and even a gang of undergraduates who’d never looked at Drosophila before can do it.
We’ve got another experiment in progress, a mapping cross that we started before spring break — we have to overlap experiments a little bit so we can get them all done in a single semester. I’m impressed with this bunch, though. They’ve got the potential to be fabulous geneticists. So hire them after they graduate!
(I don’t actually expect most of them to want to go on to careers in genetics, but they could. They have the potential.)
Congrats!
One of the fun things about doing actual labs is getting data and seeing that random chance has an effect… but it goes down with more data. Back when I taught, having students first analyze their own results for a lab, then look at the class results to see if increased measurements helped get something more in line with theory, was always a nice part of the labs.
This is why there are so many cannabis strains around these days.