4 Why did people give up hunting and gathering?

"Why not?" might be the popular response. Yet over 40 years ago anthropologists argued convincingly that for some modern hunter-gatherers, life was almost idyllic – unlike the stressful, labour-intensive, disease-ridden lot of farmers. The what and when of the first "farming" in Britain (defined by foodstuffs rather than any resemblance to modern practices) are reasonably well known. Around 4000BC, new resources (wheat and barley, sheep and cattle), crafts (pots, different stone tools) and houses (large rectangular, not small round) appeared in England and rapidly spread across Britain and Ireland. Hunter-gatherer knowledge acquired over millennia seems to have been snuffed out; people stopped fishing. The technologies and foods ultimately originated in the near east, and Britain was a late adopter. But why so sudden and so thorough? Were the natives, as some archaeologists say, so impressed with the new culture that they rushed to follow it? Had the old life been nasty and brutish? Or did resource-hungry immigrants disrupt and eradicate a successful tradition, or even the hunters themselves? The answers to such questions will tell us much about ourselves, and our land.

Roman shaped Britain Michael Fulford

Without the fruits of archaeological investigation we would know almost nothing about the four to five centuries when Britain was either ruled directly by Rome or its affairs strongly influenced by the Roman empire. For the first time Britain was part of a world power whose influence extended deep into Africa, Asia and Europe. The significance of those centuries endures to this day in the political shape of the United Kingdom. Significant elements of our road network and many of our great pre-industrial towns and cities also originated in the Roman period. Without archaeological research we would have little understanding of some of the iconic monuments of our island from the northern frontier systems of the Antonine Wall and Hadrian's Wall, to the spa town of Bath and the massive coastal forts of south-east England. The very limited written sources, such as Tacitus's biography of Agricola, governor of Britain in the late first century AD, merely whet our appetite for greater knowledge and understanding of our Roman past.

Michael Fulford is professor in archaeology, Reading University, and director of the Silchester Town Life Project.

5 Why was Stonehenge built?

Not long ago, archaeologists said they could not answer this, so should not ask it. Times change. Archaeologists have worked hard to develop ways of using apparently intractable data to solve such key "why" queries, and now university press offices out-compete retired engineers and astronomers with speculations about one of the world's best known ancient sites. Stonehenge theories have moved from the narrow, technical (solar observatory), through the vague (temple) to the ritually specific (a place for healing, pilgrimage or ancestors). There is a new awareness that fieldwork in the surrounding landscape, recently conducted on a large scale, can take us closer to explaining Stonehenge. Attempts so far have largely invoked religion, but as excavations are analysed and the new precision of radiocarbon dating is exploited, other factors including economics, politics and social change are likely to play a part in understanding a world able to bequeath such a unique and enduring monument.