Back from South Africa - #dimensionsZA

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Protea canaliculata at Teeberg in the Swartberg Pass, South Africa
Photograph by Kent Holsinger
Click on the image for a high-resolution image in a new window.

I left Capetown about 8:00pm last Thursday (2:00pm EDT), and I arrived back in Hartford just before 7:00pm EDT on Friday (1:00am Saturday in Capetown, 29 hours after I left). The flight was long, but uneventful.

My personal bag and, more importantly, the duffle with DNA samples arrived with me. The trip was a great success.

The focus of this trip was to collect samples in a hybrid zone between Protea punctata and Protea venusta at Blesberg and to collect additional samples of both species in areas of Swartberg Pass where they are not known to be hybridizing.

Nora will use the samples to unravel the dynamics of this hybrid zone. She left dataloggers in place at Blesberg to record temperature and humidity for the next year. She'll use the results from analysis of RAD SNPs (more on that in a moment) to develop a hybrid index, look at performance of individuals along the steep environmental gradient, and relate individual performance to traits. In addition, she collected seed for half-sib families which she'll use for paternity analysis to determine whether there are asymmetries in gene exchange and to identify the causes of any asymmetry she detects.

The hybrid zone is also of great interest for the Dimensions of Biodiversity project. Justin will use RAD sequencing to identify a large number of polymorphic SNPs. We'll use those SNPs as markers in a genome-wide association study to dissect the genetic basis of traits that distinguish these two very different species.

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Protea venusta at Blesberg, ca. 20km east of Klaarstoom, South Africa
Photograph by Kent Holsinger
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Nora and Jane did remarkable work in getting all of the samples. Notice I said "Nora and Jane did remarkable work." I bagged out on a lot of it. I made it down the slope at Blesberg on the first day of work there. That's a Protea venusta in the foreground about 2/3 of the way to the bottom. What the photograph doesn't show is that the only way to where we were when I took it was down the cliffs in the background. We were about 200m below the top when I took the photo. The other thing the photo doesn't show is that it had rained heavily the day before so that the rocks and restios were slick.

On the first day of work at Blesberg, I know that I slowed things down, because I'm not as sure on my feet as Nora and Jane. On the second day, I started down again and was making progress slowly. But as I was clambering down a particularly steep pitch about 150m from the top my legs started to give out. It wasn't just that I was moving slowly. I was afraid that if I descended any further, I wasn't going to make it back to the top. I asked Nora and Jane to go on without me. I climbed back to the top by myself -- slowly -- and waited for them to return.

For the next two days I didn't even try to make the descent and help. I collected some samples of Protea montana and looked for more than the single individual of Protea pruinosa -- without success. But Nora and Jane made the trip quicker every day, even though the conditions got worse.

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Nora (on the left) and Jane (on the right) heading down from the top of Blesberg on one of those days where I wimped out and stayed on top.
Photograph by Kent Holsinger
Click on the image for a high-resolution image in a new window.

At least it didn't snow while we -- they -- were working on Blesberg. A few days later we were working in Swartberg Pass. I made the (short) steep hike to Waboomsberg without a hitch. It was cold and windy, but the trail was dry. We quickly found the 20 individuals of Protea venusta we went for and returned to the pass. Then I even managed to remember where the Protea venusta population in the pass was better than Jane. I was pretty proud of myself about that.

The next day, we were planning a longer, 14km hike to Oliewensberg (7km each way), but we passed a policeman on our way up to the pass, and when we arrived at Teeberg, we decided to turn around. The road was covered with ice and snow. I'm sure our 4x4 would have made it, but we were 200m or so below the summit, and the hiking conditions would have been even worse.

We left Prince Albert the next morning making contingency plans, since we didn't think the snow would have melted and we didn't expect to be able to collect samples. To our surprise, the drive to the summit was pretty easy, so we started up the path. At first, the going wasn't bad, occasional patches of snow, but the trail was mostly bare, although it was a bit wet.

Once again it became clear that I was going to slow Nora and Jane down, but since we had plenty of time, and I was only slowing them down a little, we kept going. At about kilometer 3, though, things changed. The going got very steep, which would have been fine had the trail been clear. Unfortunately, it was covered in 10-15cm of heavy, wet snow. I was climbing through it -- very, very slowly. Nora and Jane waited for me at the top of an intermediate summit, and just before I got there, I looked at my watch. We'd come about 3.5km in an hour, and we had another 3.5km to go -- under worse conditions. This time I could have made it, but I was moving so slowly because of my unsteadiness, it would have taken us another couple of hours to get to where we needed to sample. And once I arrived, I wouldn't have been able to help. I told them to go on without me, and I went back to the summit and waited in the car.

In the end, Nora and Jane got a lot of really good samples. We even picked up several taxa for the trait-environment analysis in Dimensions that we hadn't sampled before. So it was a very successful trip. At the same time, I began to wonder about my future in South Africa during the flight home.

Nora needs someone dependable, i.e. someone other than me, to help her when she goes back next year. We've collected samples and trait data from all of the taxa it's reasonable to imagine we can get for our trait-environment analyses. Jane doesn't need me as a field assistant for her polymorphism work. I can't think of a good reason that anyone should spend good money to get me to South Africa next year.

I don't like thinking this, but I have to wonder whether 2013 may have been my swan song.