Project 3:	The Evolutionary Context of Humans and the Integration of Post-Genomic Research
Principal Investigator:	Dr. Robert A. Foley
Collaborators:	Dr. Marta Mirazón Lahr, Dr. Jay Stock, Prof. Barry Keverne, Prof. Pat Bateson, Dr. Nick Mundy
Funding:	The Leverhulme Trust

At the centre of all biological problems lies evolution, and this must be true for post-genomics. Taking evolution 'into account' requires two major concerns: the first of these is related to mechanism and function - i.e. how whole organism traits can be interpreted in terms of selection and other evolutionary mechanisms; the second is a concern with history, or the actual context in which these mechanisms took place. The co-ordinating theme of the post-genomics initiative will therefore be focused on human evolution. The contextual emphasis of this theme relates to its co-ordinating role, and this will structure the research carried out.

The work on genomic imprinting is concerned with the mammalian and primate heritage in development. Much of the interest in this field lies in the allocation of maternal resources to the developing offspring, and conflicts that may arise between mother, father, and offspring, particularly in relation to brain development. During the course of human evolution two very significant and linked changes have occurred that are directly relevant to this; the first is the enlargement of the brain, and the other the extension of periods of growth and longevity. In effect these signal the changing development of humans. The relationship between the timing and selective basis for this and genomic imprinting is an emerging issue, and one that requires a strong input in terms of understanding the evolution of maternal strategies and paternal investment. The evolutionary context for this is the long-term evolution of Homo over the last 3 million years, and requires, in particular, research into the energetic basis for brain enlargement and life history extension.

The research into heterochrony and allometry extends this theme. Changes in the human phenotype are the outcome of relationships between the rate of growth and the timing of events in relation to shape outcomes. This has occurred over several timescales, and the evolutionary context can provide both a macroevolutionary (long term human evolution), and microevolutionary context (the diversification of human populations in the last 100,000 years.). The former is essential for understanding the unique and universal characteristics of human growth relative to other animals, the latter for exploring the ecological and cultural basis for human adaptability seen today. This latter aspect is one that is now being strongly driven by the emerging knowledge of human genetic diversity, one of the major outcomes of the HGP and its sister programme, the HGDP.

The research to be carried out on phenotypic plasticity and epigenesis, links to human evolution through a concern with the interactions between growth, ecology and behaviour. The notion of sensitive periods in growth, where survival is dependent upon information received from the environment, is particularly important for humans, given their prolonged maturation and, in effect, the extension of sensitive periods of development. An evolutionary perspective can provide insights into the conditions under which the growth patterns changed, explore anthropological variation into maternal and paternal strategies, as well as the ecological and behavioural context for selection in relation to affluent and deprived uterine environments that lie at the basis of the thrifty phenotype model.

The final research theme, the ecological patterning of human growth and development, takes the ecological context further still. Human development is a dynamic process, and the variation seen today exists in a specific demographic and historical context - in other words, it is the outcome of evolutionary history. Molecular genetics is doing much to unravel that evolutionary history, and is providing information on how genetic variation relates to major ecological changes - for example, the adoption of agriculture at different times in different parts of the world, or the extent to which populations may be recent migrants or long term adaptive outcomes to local conditions. The integration of genetic and palaeoanthropological approaches to the study of human growth, and in particular the diversification of human populations over the last 100,000 years, is perhaps one of the most important post-genomic initiatives.

In sum, human evolution provides the framework for interpreting ourselves as whole organisms. Evolutionary biology can provide an explanatory framework in terms of the mechanisms that give rise to particular biological features and systems. The work of the other four research themes will be explicitly evolutionary, but it is only through their integration with the historical dimension that the patterns emerging can be linked to particular ecological contexts, and show how pattern and process are related. The study of human evolution from a post-genomic perspective - that is, the integrated use of both genetic and anthropological information - will provide a means of linking biological mechanisms (e.g. genomic imprinting) and the unique features of humans (e.g. larger brains), to the broader field of evolutionary biology. The research to be carried out will be directed both at the investigation of the ecological and behavioural context for the evolution of humans as a whole (i.e. over a period of millions of years), and the diversification of the human population in the last 100,000 years.