Final Activity Report Summary - PLEISTOCENE GENETICS (The genetics of climate change in the Late Pleistocene)
During my two years as a Marie Curie Fellow, my research focussed on the investigation of past changes in population size, extinctions and recolonisations in relation to past changes in climate. The research was mainly focussed on two species, namely the woolly mammoth and the red deer. Along with several national and international collaborators, I worked on the following projects:
1. a comparative study on 15 woolly mammoths using sequences from the full mitochondrial genome, in which we estimated the differentiation between two highly differentiated variants of the mitochondrial genome that diverged one to two million years ago. We also showed that the loss of one of the variants, some 40 000 years ago, was most likely the result of random processes rather than natural selection.
2. a population-level study on woolly mammoth, using shorter mitochondrial deoxyribonucleic acid (DNA) sequences, via which we analysed a large number of samples in order to identify pas population dynamics. Preliminary results suggested an extinction event in Europe at the end of the last Ice Age, followed by a recolonisation from Siberia a few thousand years later. The last remaining population of the mammoth, on Wrangel Island, did however not go through any dramatic genetic changes. We rather observed a gradual decline in genetic variation as the final extinction event approached.
3. a study on red deer populations in Eurasia using mitochondrial DNA, where we observed contrasting histories in Europe and Siberia. During the coldest stage of the last Ice Age, red deer seemed to have been confined to the southernmost parts of Europe. In Siberia, on the other hand, preliminary results suggested a continuous presence of red deer throughout the late Pleistocene and up until only a few hundred years ago.
4. a study on nuclear genetic diversity in the woolly mammoth. Nuclear DNA was much more difficult to recover from old samples, and has therefore been infrequently used in ancient DNA studies. Here, we performed the first ever population-level study on an Ice Age species using nuclear DNA, by analysing genetic diversity in a sample of particularly well preserved mammoths from northeast Siberia. The results suggested few genetic changes in this geographic region between 60 000 and 12 000 years ago.
1. a comparative study on 15 woolly mammoths using sequences from the full mitochondrial genome, in which we estimated the differentiation between two highly differentiated variants of the mitochondrial genome that diverged one to two million years ago. We also showed that the loss of one of the variants, some 40 000 years ago, was most likely the result of random processes rather than natural selection.
2. a population-level study on woolly mammoth, using shorter mitochondrial deoxyribonucleic acid (DNA) sequences, via which we analysed a large number of samples in order to identify pas population dynamics. Preliminary results suggested an extinction event in Europe at the end of the last Ice Age, followed by a recolonisation from Siberia a few thousand years later. The last remaining population of the mammoth, on Wrangel Island, did however not go through any dramatic genetic changes. We rather observed a gradual decline in genetic variation as the final extinction event approached.
3. a study on red deer populations in Eurasia using mitochondrial DNA, where we observed contrasting histories in Europe and Siberia. During the coldest stage of the last Ice Age, red deer seemed to have been confined to the southernmost parts of Europe. In Siberia, on the other hand, preliminary results suggested a continuous presence of red deer throughout the late Pleistocene and up until only a few hundred years ago.
4. a study on nuclear genetic diversity in the woolly mammoth. Nuclear DNA was much more difficult to recover from old samples, and has therefore been infrequently used in ancient DNA studies. Here, we performed the first ever population-level study on an Ice Age species using nuclear DNA, by analysing genetic diversity in a sample of particularly well preserved mammoths from northeast Siberia. The results suggested few genetic changes in this geographic region between 60 000 and 12 000 years ago.