Neolithic farmers brought deer to Ireland

The origins of the iconic Irish red deer was a controversial topic. Was this species native to Ireland, or introduced?

In a new study that was published 30 March 2012 in the scientific journal Quaternary Science Reviews, a multinational team of researchers from Ireland, Austria, UK and USA have finally answered this question.

Comparing DNA

By comparing DNA from ancient bone specimens to DNA obtained from modern animals, the researchers discovered that the Kerry red deer are the direct descendants of deer present in Ireland 5000 years ago. Further analysis using DNA from European deer proves that Neolithic people from Britain first brought the species to Ireland.
Although proving the red deer is not native to Ireland, researchers believe that the Kerry population is unique as it is directly related to the original herd and are worthy of special conservation status.

A link to the past

Fossil bone samples from the National Museum of Ireland, some up to 30,000 years old, were used in the study. Results also revealed several 19^th and 20^th century introductions of red deer to Ireland, which are in agreement with written records from the same time. At present there is no evidence of red deer in Ireland during the Mesolithic period, 9000 years ago, when humans first settled there.

Neolithic house, Irish National Heritage Park. Image: David Hawgood (Geograph, used under a CC BY-SA 3.0)

The investigation’s findings are in agreement with archaeological evidence, which also suggests a special relationship between humans and red deer during later prehistoric times. Antler fragments and tools are frequently found in Neolithic, Bronze Age and Iron Age excavations.
Dr Ruth Carden, working as a researcher in the National Museum of Ireland, who led the study, said “The Kerry red deer represent a unique population within an Irish context and therefore should be given special conservation and management status within Ireland.”
The genetic analysis also showed that some of these herds were descended from animals imported from Britain in the 1800s and 1900s, matching the historical records.
The DNA showed that the reds away from Kerry have started to “hybridise” or cross-breed with Sitka deer, a species introduced here in 1860. There is however no such interbreeding for the Kerry red population, Dr Carden added. Sitkas also live in the forests of Killarney but the DNA analysis showed no interbreeding had yet taken place.
Dr Allan McDevitt, from the School of Biology and Environmental Science, University College Dublin, one of the lead geneticists said “We have very few native mammals in Ireland but certainly those that arrived with early humans, such as the red deer, are every bit as Irish as we are.”
Source: School of Biology and Environmental Science, University College Dublin

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More information:

R F Carden, A D McDevitt, F E Zachos, P C Woodman, P O’Toole, H Rose, N T Monaghan, M G Campana, D G Bradley, C J Edwards (2012). Phylogeographic, ancient DNA, fossil and morphometric analyses reveal ancient and modern introductions of a large mammal: the complex case of red deer (Cervus elaphus) in Ireland. Quaternary Science Reviews. doi: 10.1016/j.quascirev.2012.02.012
School of Biology and Environmental Science, University College Dublin
The Heritage Council, Ireland
Woodman P.; McCarthy M.; Monaghan N., (1997) The Irish quaternary fauna project: Quaternary Science Reviews, Volume 16, Number 2, 1997 , pp. 129-159 http://dx.doi.org/10.1016/S0277-3791(96)00037-6

Report on the symposium on Modern Human Genetic Variation

This image shows the chronology of the Neolithic wave of advance in Europe. The arrow corresponds to the Y-direction in the model. Credit: http://iopscience.iop.org/1367-2630/12/12/123002/pdf/1367-2630_12_12_123002.pdf



The following text is taken from the http://dienekes.blogspot.com/


Joshua Akey summarizes the talks of a recent symposium at the Swedish Royal Academy of Sciences. Two bits of information stand out from his report. The first:

In another talk focused on demography, Mattias Jakobsson (Uppsala University, Sweden) presented novel data on the impact of the agricultural revolution on the genetics of contemporary European populations. Specifically, Jakobsson and colleagues obtained nearly 250 Mb of sequence from three 5,000-year-old remains of Neolithic hunter-gatherers and one Neolithic farmer excavated in Scandinavia. Analysis of these sequences in the context of the present day European gene pool suggests that the spread of agriculture involved the northward migrations of farmers. Thus, these data provide the most direct and compelling support for the demic diffusion model of agriculture (as opposed to cultural diffusion) described to date.

It seems I have my answer to the what's next question. Jakobsson has been doing some interesting work on the demography of human emergence and dispersal, so it will be interesting to see not only the novel sequences from these Neolithic Scandinavians, but also how they fit into existing models of demic diffusion.

The second bit of information:

Similarly, Jeff Wall (University of California San Francisco, USA) described a novel method for inferring archaic admixture, which he applied to publicly available whole-genome sequence data generated by Complete Genomics. Provocatively, he finds higher rates of introgression in Asians compared to Europeans. An advantage of Wall’s method is that it does not require an archaic genome to infer introgression, and thus he was able to also test the hypothesis that contemporary African genomes have signatures of gene flow with archaic human ancestors. Strikingly, Wall indeed did find evidence of archaic admixture in African genomes, suggesting that modest amounts of gene flow were widespread throughout time and space during the evolution of anatomically modern humans.

I guess that I shouldn't throw explanation #1 out the window yet. Wall was involved in the recent paper on archaic African admixture, which only looked at a small subset of the genome, so it is nice to see that he is now working with full genomes, and that the race to data mine complete genomes for archaic admixture is afoot.

The book of abstracts is online at the symposium site. The Jakobsson paper does seem to agree with our emerging picture of a non-local origin of northern European farmers as well as greater survival of pre-farming populations in the northern periphery of Europe, but it will be interesting to see where exactly extant populations fall on the farmer-hunter/gatherer continuum.


Origins and genetic legacy of Neolithic farmers and hunter-gatherers in Northern Europe
Mattias Jakobsson

Department of Evolutionary Biology, Evolutionary Biology Centre (EBC), Uppsala University, Sweden

The prehistoric spread of farming in Europe has garnered intense interest for almost a century, and was one of the first questions to which population genetic data was used to investigate demographic hypotheses. However, the impact of the agricultural revolution on the European gene pool remains largely unknown. We obtained 249 million base pairs of quality-filtered human autosomal sequence data from some 5,000 year-old remains of three Neolithic hunter-gatherers and one Neolithic farmer excavated in Scandinavia, the northernmost fringe of agricultural practice at the time. Applying novel methods to study population structure based on low genome-coverage data, we find that Northern European Neolithic farmers are most similar to modern-day southern Europeans, contrasting sharply to Neolithic hunter-gatherers who are most similar to extant individuals from northern Europe. With most extant European populations appearing genetically intermediate between the two Neolithic groups, our results suggest that migration from the south by a genetically distinct group of humans accompanied the spread of agriculture to geographic regions where hunting and gathering was the mode of subsistence, but that admixture eventually shaped modern-day patterns of genomic variation.

Archaic admixture in the human genome
Jeff D Wall

Department of Epidemiology & Biostatistics, University of California, San Francisco, USA

We describe a method that uses patterns of linkage disequilibrium in extant human populations to identify regions of the genome that were inherited from ‘archaic’ human ancestors, such as Neandertals, Homo erectus or H. floresiensis. We validate this approach using two recently published archaic human genomes, and show that several ancient admixture events must have occurred, both within and outside of Africa. We also explore differences in the amount of archaic admixture across different contemporary human populations.


Finally, here is the meeting report:

Investigative Genetics 2012, 3:7 doi:10.1186/2041-2223-3-7

Understanding human evolutionary history: a meeting report of the Swedish Royal Academy of Sciences symposium of modern human genetic variation

Joshua M Akey

LINK (PDF)