Test 04

|Part 1|

The Romans Reveal their Secrets

As Katherine Sheen rested on the banks of Hensham river on 3 August 2005, her gaze fell upon a small dirt-covered object amongst a tangle of tree roots. Cleaning away the soil, she realized it was a leather pouch. It fell apart as Katherine opened it, and the items inside fell to the ground. Although her university degree merely touched on the Roman occupation of ancient Britain, providing a very general overview of everyday activities, once she’d rubbed off some the dirt, Katherine immediately identified the coins in her hand as coming from that era. Despite their discoloration, Katherine had no doubt they were historically significant. As soon as she got home, she informed the police of her find.

That might have been the end of the story – except for the fact that the farmer who owned adjacent field then mentioned the lines of large stones his plough kept running into. By mid-August, with the farmer’s permission, a team of archaeologists, led by Professor Kevin Durrand, were camped out in the field. Durrand had previously worked on other projects where pieces of ancient pottery and the discovery of an old sword had led archaeologists to unearth sizeable Roman settlements. He was keen to start excavations at Hensham, and had got funding for a three-month dig. What his team eventually discovered, three weeks into excavations, were the remains of the outer walls of a Roman villa. As many Romans in Britain simply lived in wooden houses with thatched roofs, the family that occupied the villa must have been very wealthy. As the team continued their work, they looked for evidence that might indicate whether the villa had been attacked and purposely demolished, or fallen into such a poor state that it eventually collapsed. Looking at the way a set of slate roof tiles had fallen to the ground, they decided on the latter. What caused the noble Roman family and their servants to abandon the villa remains open to speculation.

Another find was six blue beads, crafted from glass, which the archaeologists speculated were part of a necklace. Durrand has previously found gold bracelets on other sites, but for him the beads are no less significant. ‘Every find contributes to the story’, he says. On the outer western wall, the archaeologists uncovered a number of foundation stones. On one is carved what the archaeologists made out to be a Latin inscription. But as the stone itself has endured centuries of erosion, the team has yet to work out what it says. Another find was a section of traditional Roman mosaic. Although incomplete, enough pieces remain to show a geometrical pattern and stylized fish. From this, Durrand assumes that a bath house would have been a feature of the villa. While his team have so far not found any hard proof of this, Durrand is confident it will turn out to be the case.

Something that the team is particularly excited about is evidence of a heating system, which would have served the Roman family and their visitors well in winter months. Although much of the system has long since crumbled at Hensham, Durrand and his team believe it would have been based on a typical Roman hypocaust; they have created a model for visitors to see. The furnace that produced the hot air needed to be kept burning all the time, a task that would have fallen to the villa’s slaves. As large branches would have taken too long to produce the heat required, it is more likely that twigs would have been gathered from surrounding woodland instead. Another fuel source used in some Roman hypocausts was charcoal, but evidence for this at Hensham has not presented itself.

The underfloor space was made by setting the floor on top of piles of square stones. Known as pilae, these stones stood approximately two feet high. The gap this created meant that the hot air coming out of the furnace was not trapped and restricted. Instead its distribution around the pilae and under the floor was free flowing. Floor tiles were not placed directly onto the pilae but separated by a layer of concrete, or at least a primitive version of it. This would have made the whole structure more solid, and helped reduce the risk of fire spreading to upper levels. The walls of the rooms above the heating system were made of bricks, but the key point here is that they were hollow, in order to allow heat to rise around the rooms and provide insulation. Some have been recovered from the Hensham villa and are now undergoing preservation treatment.

Another feature of the heating system that archaeologists have identified at Hensham was its clay pipes. These were cleverly built into the wall so as not to take up space. The principal reason for including the pipes was to let out air through a vent in the roof once it had cooled down. What the Romans may not have realised, however, was that gas produced by the burning fuel was expelled in this way too. In high doses, it could have been lethal if it had leaked into the upper levels. Inside the rooms in the villa, a layer of plaster would have been applied to the walls and painted in rich colours. Sadly, none of the original plaster at Hensham still exists. However, some of the tiles that the family would have walked on have survived. They would certainly have felt warm underfoot and helped generate an indoor climate that the family could relax in. In its day, the Hensham hypocaust would have been a remarkable piece of engineering.

|Part 2|

The Truth about Lying

A An area of scientific study that caught the public imagination during the 1970s involved a gorilla called Koko. Animal psychologist Francine Patterson claimed to have taught Koko a simplified form of American Sign Language, and through signing, Koko could apparently communicate basic ideas such as ‘food’ and ‘more’, as well as concepts such as ‘good’ and ‘sorry’. But Koko also used signs to blame other people for damage she had caused herself. While today there is some dispute about whether Koko truly understood the meaning of all the signs she made, Professor Karen Goodger believes she was certainly capable of dishonesty. ‘People use words to lie, but for animals with higher brain functions, there’s also a higher probability that they’ll demonstrate manipulative behaviours. We see this not just in gorillas, but in other creatures with a large neocortex.’

B Human societies may appear to disapprove of lying, but that doesn’t mean we don’t all do it. And it seems that the ability, or at least the desire to deceive, starts from an early age. In one study run by psychologist Kang Lee, children were individually brought into a laboratory and asked to face a wall. They were asked to guess what toy one of Lee’s fellow researchers had placed on a table behind them – for example, a fluffy cat or dog. The researcher would then announce they had to leave the lab to take a phone call, reminding the child not to turn around. The research team were well aware that many children would be unable to resist peeking at the toy. Secret cameras showed that 30% of two-year-old children lied about not looking. This went up to 50% for three-year-olds and almost 80% of eight-year-olds. Interestingly, whereas the younger children simply named the toy and denied taking a peek, the older ones came up with some interesting reasons to explain how they had identified the toy correctly. Lee is reassured by this trend, seeing it as evidence in each case that the cognitive growth of a human child is progressing as it should. Parents, of course, may not be so pleased.

C Adults, however, can hardly criticise children. According to Professor Richard Wiseman, it appears that adults typically tell two major lies per day, and that one third of adult conversations contain an element of dishonesty. Other research indicates that spouses lie in one out of every 10 interactions. This probably comes as no surprise to Tali Sharot at University College London, who has run a series of experiments proving we become desensitised to lying over time. She has found that while we might initially experience a sense of shame about small lies, this feeling eventually wears off. The result, Sharot has found, is that we progress to more serious ones.

D Other researchers, including Tim Levine at the University of Alabama, have analysed our motives for lying. By far the most common is our desire to cover up our own wrongdoing. Second to this are lies we tell to gain economic advantage – we might lie during an interview to increase the chances of getting a job. Interestingly, ‘white lies’, the kind we tell to avoid hurting people’s feelings, account only for a small percentage of our untruths. But if we recognise our own tendency to lie, why don’t we recognise it in others? Professor Goodger thinks it has something to do with our strong desire for certain information we hear to be true, even when we might suspect it isn’t. This is because we might be ‘comforted by others’ lies or excited by the promise of a good outcome’, Goodger says.

E We might not expect ordinary people to be good at recognising lies, but what about people whose job it is to investigate the behavior of others? Paul Erkman is a psychologist from the University of California. As part of his research into deception, he has invited a range of experts to view videos of people telling lies and of others telling the truth. Among the experts have been judges, psychiatrists and people who operate polygraph machines for police investigations. None of these experts have shown they can detect dishonestly any better than people without their experience. Part of the problem is that so many myths still prevail about ‘give-away signs’ indicating that someone is lying.

F A common claim, for example, is that liars won’t look people in the eye during their explanations or while being questioned. Another is that they are likely to gesture as they tell their story, but so frequently that it seems unnatural – as if they are trying to convince others of their sincerity. However, many researchers have come to reject these ideas, suggesting a more effective approach is to listen to their narration style. A difficulty that liars face is having to remember exactly what they said, which is why they don’t provide as many details as a person giving an honest account would. It is also typical of liars to mentally rehearse their story, and this is why one stage follows another in apparently chronological fashion. Honest stories, however, feature revisions and repetition. Recent research has also disproved the widely believed notion that liars have a habit of fidgeting in their seats. Rather, it seems that they keep still, especially in the upper body, possibly hoping to give the impression of self-assurance. Liars also put some psychological distance between themselves and their lies. For that reason, they avoid the use of ‘I’ when narrating their stories. The reverse is true, however, when people write fake reviews, say, a hotel or restaurant. In these instances, ‘I’ features again and again as they attempt to convince use that their experience was real.

|Part 3|

Review: The Hidden Life of Trees by Peter Wohlleben

That so many copies of Peter Wohlleben’s book The Hidden Life of Trees have been sold is no surprise. Life in the urban jungle can be overwhelming, and many of us long to escape by seeing more natural environments. We hope an encounter with nature might make us feel more ‘alive’. Would we use this same term to describe nature itself, though? Forests and the trees that form them are commonly perceived as objects lacking awareness, like rocks or stones. But here, Wohlleben would beg to differ. From his observations, he has concluded that they are conscious in a way we do not fully understand.

In recent decades, a number of writers have investigated our planet’s flora. The Cabaret of Plants by Richard Mabey and What a Plant Knows by Daniel Chamovitz, for example, have done much to reformulate our views about the green world. Central to many of these books is a serious message about sustainability, and The Hidden Life of Trees is no exception. What sets it apart is its approach to description: at the start Wohlleben announces that ‘When you know the trees … have memories and that tree parents live together with their children, then you can no longer just chop them down.’ Not everyone will be comfortable with this kind of anthropomorphism.

Nevertheless, Wohlleben’s experience of working in a beech forest in the Eifel mountains of Germany may put him in a better position than many to write a book about trees. In the introduction, he explains that he started out as a state-employed forester, taking care of trees purely for industrial reasons. The straighter they were, the more high-quality logs could be sawn. But after a while he began to appreciate trees for more than just their commercial worth. He gives some of the credit for this realisation to the tourists that would come to the forest, who were more enchanted by bent, crooked trees, which did not conform to the straight ideal.

An anecdote that stands out is Wohlleben’s encounter with ‘the gnarled remains of an enormous tree stump’ in the Eifel forest. More than anything else, it was this encounter that prompted him to look further into the hidden behaviour of trees. To his surprise, after scraping at the outside layer of bark covering the stump, he discovered a green layer underneath. This was chlorophyll, the pigment normally produced by living trees. Wohlleben realised that the only way the stump could still be alive was if the surrounding beeches were providing it with a sugar solution through their own roots.

Wohlleben is not the first person to claim that trees are cooperative. In the 1990s, Dr Suzanne Simard realised that fir and birch trees were supplying each other with carbon. Simard’s findings made complete sense to Wohlleben, who believes that this kind of nutrient exchange between neighbours is typical of a healthy forest. Wohlleben also had the opportunity to deepen his understanding of tree biology when researchers from Aachen University set up investigative programmes in his beech forest. Discussions with them reinforced his beliefs about the way trees thrived, and Wohlleben eventually found himself strongly opposed to some traditional forestry practices. He finally succeeded in persuading local villagers that the forest should be allowed to return to a natural state: this involved banning the use of machinery for logging, and giving up on pesticides for a start. Since then, Wohlleben has been noting how his beech forest has developed, and his observations formed the foundation for the book.

Humour and straightforward narrative make it instantly appealing to readers without a science background – elements that have successfully been translated into over a dozen languages. Those that do have scientific training, however, will be more demanding. Critics of Wohlleben point out that proper academic studies need to be done to prove all his claims are factually accurate. This seems a fair point. What the book will certainly do is transform nature lovers’ experiences of a forest walk. Once you know what is happening below ground, you can’t help but marvel at the complex life of trees. Will it transform the way we produce timber for the manufacturing industry? As large corporations tend to focus on immediate profits, they are hardly likely to adopt the longer-term practices that Wohlleben recommends.

One of these is allowing trees to grow nearer to each other. This is the opposite of what happens in many state-owned forests, where foresters deliberately space out trees so they can get more sunlight and grow faster. But Wohlleben claims this spacing prevents vital root interaction, and so lowers resistance to drought. Older, established trees, he explains, draw up moisture through their deep roots and provide this to juvenile trees growing below them. Fungal interaction is also given attention. For instance, when pines require more nitrogen, the fungi growing at their base release a poison into the soil. This poison kills many minute organisms, which release nitrogen as they die, and this is absorbed by the trees’ roots. In return, the fungi receive photosynthesised sugar from pines. Then Wohlleben explores the way trees employ scent, giving the example of acacia trees in sub-Saharan Africa. When giraffes begin feeding on an acacia’s leaves, the tree emits ethylene gas as a warning to neighbouring acacias. These then pump tannins into their leaves – substances toxic to giraffes. More controversial is Wohlleben’s suggestion that trees feel pain. Although scientific research has now established that if branches are broken off or the trunk is hit with an axe, a tree will emit electrical signals from the site of the wound, the application of the concept of ‘pain’ might be an instance where readers are unconvinced.