Domestic robots
Machines that look after your home are getting cleverer, but they still need care and attention if they are to perform as intended

Floor-cleaning machines capable of responding to their environment were among the first commercially available domestic products worthy of being called robots. The best known is the Roomba, made by iRobot, an American company which has sold more than three million of the disc-shaped, frisbee-sized vacuuming robots. The latest model, the fifth version of the Roomba, has more sensors and cleverer software than its predecessors. Press the 'Clean' button and the robot glides out of its docking station and sets off across the floor.
Domestic robots are supposed to free up time so that you can do other things, but watching how the Roomba deals with obstacles is strangely compelling. It is capable of sensing its surroundings, and does not simply try to adhere to a pre-planned route, so it is not upset if furniture is moved, or if it is picked up and taken to clean another room. Its infra-red sensors enable it to slow down before reaching an obstacle - such as a dozy cat- changing direction and setting off again. 
It steadily works its way around the room, figuring out how to get out from under the television stand or untangle itself from a stray Game Boy recharging lead. Watch it for long enough, and you can sometimes predict its next move. The machine has a 'dirt sensor' and flashes a blue light when it finds things to
clean up. Only when it detects no more dirt does it stop going over the same area and, eventually, conclude that the whole room is clean. It then trundles back to dock at its recharging station. 
So the first observation of life with a domestic robot is that you will keep watching it before you trust it completely. Perhaps that is not surprising: after all, when automatic washing machines first appeared, people used to draw up a chair and sit and watch them complete their wash, rinse and spin cycles. Now
they just load them, switch them on and leave them to it.
The second observation is that, despite their current level of intelligence, certain allowances must be made to get the best out of a domestic robot. The Roomba can be set up to clean at particular times, and to clean more than one room (small infra-red 'lighthouses' can be positioned in doorways, creating an invisible barrier between one room and the next that is only removed when the first room has been cleaned). A 'drop-off' sensor underneath the robot prevents it from falling down stairs. All very clever, but what the Roomba will not do is pick up toys, shoes and other items left lying around. Rooms cared for by robots must be kept tidy. To start with, children will happily put things away in order to watch the robot set off, but unfortunately the novelty soon wears off.
Similar allowances must be made for other domestic robots. Sweden's Husqvarna recently launched a new version of its Automower lawn mowing robot. Before it can be used, a wire must be placed around the perimeter of the lawn to define the part to be cut. If toys and other obstacles are not cleared from
the lawn before it starts work, the robot will steer around them, leaving uncut areas. However, the latest version can top up its batteries with solar power, or send its owner a text message if it gets into trouble trying to climb a mole-hill.
But there is still only a limited range of domestic robots. Machines that mop the floor, clean a swimming pool and clear muck from guttering are made by iRobot. Several surveillance robots are also on offer. The Rovio, made by WowWee of Hong Kong, is a wi-fi-enabled webcam, mounted on an extending
arm, which rides along smoothly on a nimble set of three wheels. Its movement can be remotely operated over the Internet via a laptop or mobile phone. The idea is that Rovio can patrol the home when its owner is away, either automatically or under manual control: in the latter case, two-way communication allows the operator to see and talk via the machine. So you could, for instance, shout at the cat if it is sleeping on your best sofa.
Some machines are called robots even though they cannot move around. There is an ironing robot, for instance, that resembles an inflatable dummy: put a damp shirt on it, and it puffs up to remove the creases. Similarly, there are elaborate trouser presses that aspire to be robots. But do these devices really
count as robots? If so, then surely dishwashers and washing machines do, too.
Yet whatever shape or size robots come in, many will be adored. Another important observation from living with a robot is that it tends to become part of the family. 'People give them names, and if they have to be sent back for repair, they carefully add a mark to them to ensure they get the same machine back,' says Nancy Dussault Smith of iRobot.

Deforestation in the 21st century
When it comes to cutting down trees, satellite data reveals a shift from the patterns of the past
A Globally, roughly 13 million hectares of forest are destroyed each year. Such deforestation has long been driven by farmers desperate to earn a living or by loggers building new roads into pristine forest. But now new data appears to show that big, block clearings that reflect industrial deforestation have come to dominate, rather than these smaller-scale efforts that leave behind long, narrow swaths of cleared land. Geographer Ruth DeFries of Columbia University and her colleagues used satellite images to analyse tree-clearing in countries ringing the tropics, representing 98 per cent of all remaining tropical forest. Instead of the usual 'fish bone' signature of deforestation from small-scale operations, large, chunky blocks of cleared land reveal a new motive for cutting down woods.

B In fact, a statistical analysis of 41 countries showed that forest loss rates were most closely linked with urban population growth and agricultural exports in the early part of the 21st century - even overall population growth was not as strong an influence. 'In previous decades, deforestation was associated with planned colonisation, resettlement schemes in local areas and farmers clearing
land to grow food for subsistence,' DeFries says. 'What we're seeing now is a shift from small-scale farmers driving deforestation to distant demands from urban growth, agricultural trade and exports being more important drivers.'
C In other words, the increasing urbanisation of the developing world, as populations leave rural areas to concentrate in booming citi es, is driving deforestation, rather than containing it. Coupled with this there is an ongoing increase in consumption in the developed world of products that have an impact on forests, whether furniture, shoe leather or chicken feed. 'One of the really striking characteristics of this century is urbanisation and rapid urban growth in
the developing world,' DeFries says. 'People in cities need to eat.' 'There's no surprise there,' observes Scott Poynton, executive director of the Tropical Forest Trust, a Switzerland-based organisation that helps businesses implement and manage sustainable forestry in countries such as Brazil, Congo and Indonesia. 'It's not about people chopping down trees. It's all the people in
New York, Europe and elsewhere who want cheap products, primarily food.'
D Defries argues that in order to help sustain this increasing urban and global demand, agricultural productivity will need to be increased on lands that have already been cleared. This means that better crop varieties or better anagement techniques will need to be used on the many degraded and abandoned lands in the tropics. And the Tropical Forest Trust is building management systems to keep illegally harvested wood from ending up in, for example, deck chairs, as well as expanding its efforts to look at how to reduce the 'forest footprint' of agricultural products such as palm oil. Poynton says, 'The point is to give forests value as forests, to keep them as forests and give them a use as forests. They're not going to be locked away as national parks. That's not going to happen.'
E But it is not all bad news. Halts in tropical deforestation have resulted in forest regrowth in some areas where tropical lands were previously cleared. And forest clearing in the Amazon, the world's largest tropical forest, dropped from roughly 1.9 million hectares a year in the 1990s to 1.6 million hectares a year over the last decade, according to the Brazilian government. 'We know that deforestation has slowed down in at least the Brazilian Amazon,' DeFries says. 'Every place is different. Every country has its own particular situation, circumstances and driving forces.'
F Regardless of this, deforestation continues, and cutting down forests is one of the largest sources of greenhouse gas emissions from human activity - a double blow that both eliminates a biological system to suck up C02 and creates a new source of greenhouse gases in the form of decaying plants. The United Nations Environment Programme estimates that slowing such deforestation could reduce some so billion metric tons of Co2 , or more than a year of global
emissions. Indeed, international climate negotiations continue to attempt to set up a system to encourage this, known as the UN Development Programme's fund for reducing emissions from deforestation and forest degradation in developing countries (REDO). If policies [like REDO] are to be effective, we need to understand what the driving forces are behind deforestation, DeFries
argues. This is particularly important in the light of new pressures that are on the horizon: the need to reduce our dependence on fossil fuels and find alternative power sources, particularly for private cars, is forcing governments to make products such as biofuels more readily accessible. This will only exacerbate the pressures on tropical forests.
G But millions of hectares of pristine forest remain to protect, according to this new analysis from Columbia University. Approximately 6o percent of the  remaining tropical forests are in countries or areas that currently have little agricultural trade or urban growth. The amount of forest area in places like central Africa, Guyana and Suriname, DeFries notes, is huge. 'There's a lot of
forest that has not yet faced these pressures.'

So you think humans are unique

There was a time when we thought humans were special in so many ways. Now we know better. We are not the only species that feels emotions, empathises
with others or abides by a moral code. Neither are we the only ones with personalities, cultures and the ability to design and use tools. Yet we have steadfastly clung to the notion that one attribute, at least, makes us unique: we alone have the capacity for language. 
Alas, it turns out we are not so special in this respect either. Key to the revolutionary reassessment of our talent for communication is the way we think about language itself. Where once it was seen as a monolith, a discrete and singular entity, today scientists find it is more productive to think of language as a suite of abilities. Viewed this way, it becomes apparent that the component parts of language are not as unique as the whole.
Take gesture, arguably the starting point for language. Until recently, it was considered uniquely human- but not any more. Mike Tomasello of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and others have compiled a list of gestures observed in monkeys, gibbons, gorillas, chimpanzees, bonobos and orang-utans, which reveals that gesticulation plays a large role in their communication. Ape gestures can involve touch, vocalising or eye movement, and individuals wait until they have another ape's attention before making visual or auditory gestures. If their gestures go unacknowledged, they will often repeat them or touch the recipient. 
In an experiment carried out in 2006 by Erica Cartmill and Richard Byrne from the University of St Andrews in the UK, they got a person to sit on a chair with some highly desirable food such as banana to one side of them and some bland food such as celery to the other. The orang-utans, who could see the person and
the food from their enclosures, gestured at their human partners to encourage them to push the desirable food their way. If the person feigned incomprehension and offered the bland food, the animals would change
their gestures -just as humans would in a similar situation. If the human seemed to understand while being somewhat confused, giving only half the preferred food, the apes would repeat and exaggerate their gestures-again in exactly the same way a human would. Such findings highlight the fact that the gestures of non-human primates are not merely innate reflexes but are learned, flexible and under voluntary control - all characteristics that are considered prerequisites for human-like communication.
As well as gesturing, pre-linguistic infants babble. At about five months, babies start to make their first speech sounds, which some researchers believe contain a random selection of all the phonemes humans can produce. But as children learn the language of their parents, they narrow their sound repertoire to fit the
model to which they are exposed, producing just the sounds of their native language as well as its classic intonation patterns. Indeed, they lose their polymath talents so effectively that they are ultimately unable to produce some sounds- think about the difficulty some speakers have producing the English th.
Dolphin calves also pass through a babbling phase. Laurance Doyle from the SETI institute in Mountain View, California, Brenda McCowan from the University of California at Davis and their colleagues analysed the complexity of baby dolphin sounds and found it looked remarkably like that of babbling infants, in that the young dolphins had a much wider repertoire of sound than adults. This suggests that they practise the sounds of their species, much as human babies do, before they begin to put them together in the way
characteristic of mature dolphins of their species. 
Of course, language is more than mere sound -it also has meaning. While the traditional, cartoonish version of animal communication renders it unclear, unpredictable and involuntary, it has become clear that various species are able to give meaning to particular sounds by connecting them with specific ideas. Dolphins use 'signature whistles', so called because it appears that they name themselves. Each develops a unique moniker within the first year of life and uses it whenever it meets another dolphin.
One of the clearest examples of animals making connections between specific sounds and meanings was demonstrated by Klaus Zuberbuhler and Katie Slocombe of the University of St Andrews in the UK. They noticed that chimps at Edinburgh Zoo appeared to make rudimentary references to objects by using distinct cries when they came across different kinds of food. Highly valued foods such as bread would elicit high-pitched grunts, less appealing ones, such as an apple, got low-pitched grunts. Zuberbuhler and Slocombe showed not only that chimps could make distinctions in the way they vocalised about food, but that other chimps understood what they meant. When played recordings of grunts that were produced for a specific food, the chimps looked in the place where that food was usually found. They also searched longer if the cry had signalled a prized type of food.
Clearly animals do have greater talents for communication than we realised. Humans are still special, but it is a far more graded, qualified kind of special than it used to be.