Triassic mass extinction may give clues on how oceans will be affected by climate change

Mass extinction, good news for this guy. Esparta Palma/flickr, CC BY

To hot to handle . Jessica Whiteside

Just over 200m years ago, the end-Triassic mass extinction killed off more than half of the species of organisms living on Earth’s land and in the oceans. We are only just beginning to understand how this – and the period of runaway global warming that followed – changed the chemistry of open oceans.

The end-Triassic mass extinction marked the transition between the Triassic to the Jurassic Period and the rise of the large herbivorous dinosaurs dinosaurs, such as the Diplodocus. The extinction meant that previously abundant species were cleared from ecological niches which allowed dinosaurs to move in with little competition from other animals. The Jurassic lasted another 55m years until the beginning of the Cretaceous Period.

But the extinction also had profound effects on ocean ecosystems. Previous research linked the extinction to rapid global warming and changes in ocean chemistry which were caused by massive volcanic eruptions that released large amounts of greenhouse gasses into the atmosphere. To hot to handle . jessica whiteside

One of the unanswered questions has been how global warming changed the chemistry of the oceans. Some studies provide a picture of environmental changes on land and in coastal shallow seas, but until now there has been little information on the conditions of ecosystems in open ocean areas – known as pelagic zones – where water is neither close to the seabed or the shore.

We decided to investigate this unresolved problem, as open ocean settings better reflect global conditions in comparison to shallow coastal areas, as open oceans tend not to be subject to small climatic changes experienced by other areas such as shallow coastal regions near to shore.

Toxic oceans

We extracted and analysed fossilised organic molecules – known as biomarkers – that are the remains of microscopic marine organisms from sediments deposited at the bottom of what was the north-eastern Panthalassic Ocean - the vast body of water that surround the ancient super-continent Pangaea. The sediment is now preserved as rock exposed on the coast of Haida Gwaii (also known as the Queen Charlotte Islands) off the coast of British Columbia in Canada.

Different types of biomarkers signify the presence of certain groups of organisms and allow us to track their abundance in Triassic oceans. Our results show that for a 600,000-year interval immediately after the end-Triassic mass extinction, water close to the ocean surface became devoid of oxygen and was poisoned by hydrogen sulphide, a by-product of anaerobic bacteria that is extremely toxic to most other forms of life. This oxygen depletion and hydrogen sulphide poisoning disrupted the availability of nutrients, altering the food chains and causing a major disruption of marine ecosystems.

Clues for the future

These results are similar to another major event in the geologic record that was also caused by greenhouse gas release: the end-Permian extinction, the largest-known mass extinction.

Our team’s discoveries about the end-Triassic mass extinction event have direct relevance to today’s world because we are currently experiencing a rapid rise in the atmospheric levels of the greenhouse gas, carbon dioxide (CO₂). Although the Earth was very different during the Triassic Period due to the lack of polar ice caps and higher initial CO₂ concentrations, the speed of CO₂ release from volcanic eruptions following the mass extinction is similar to those that we are experiencing today through the burning of fossil fuels.

The concern is that the consequences of rapidly rising atmospheric CO₂ levels can be expected to be similar: ocean acidification, oxygen depletion of the oceans, hydrogen sulphide poisoning and disruption of food chains through the killing off of photosynthesisers in the ocean.

Studies of ancient mass extinctions such as the one at the end-Triassic inform us of the possible consequences of our own CO₂ crisis.

System to rate the scarcity of important metals aims to keep shortage at bay

Rare earth elements, the unusual spices of the industrial world. Peggy Greb/USDA

Store cupboards usually contain the basics – canned tomatoes, soup, dry goods – but rarely the more exotic additions required in small amounts to make a dish sing. In the same way, a growing shortage of some of the rare elements needed for high-tech electronics and environmental technologies is causing manufacturers and governments to panic, with sporadic shortages leading to price spikes in some metals over the last decade.

Miners, manufacturers and governments are keen to assess the overall risk, or “criticality”, associated with different metals in order to ensure that replenishment efforts are prioritised and business can continue as usual. Of course different firms or governments will have different views, so may come up with widely varying – and hence unhelpful – estimates of criticality for the same element. But a recent study by researchers at Yale University has provided a tool based on three factors that can offer a more reliable approach to estimating metal shortfalls.

Graedel et al/PNAS

You may need only a small amount of exotic spice for your dish, but if it’s not stocked at the corner shop, it wouldn’t matter if you needed the whole jar. Similarly we can be sure that some metals – iron, aluminium – will be found in deposits suitable for mining across the world, with huge reserves that we know about – so we don’t need to worry about these dry goods equivalents. But it’s the more exotic elements such as indium and selenium, the truffle oil of our analogy, that due to geology and economics are harder to find. These are high supply risk elements, yet are essential for uses in electronics and solar cells.

Production of some metals is highly concentrated in only a few countries, leading to geopolitical risks to supply – China’s moves to restrict rare earth element exports, or strikes in South African platinum mines are recent examples.

Just like that bagged, mixed salad that’s so convenient, but wastefully irrigated and flown to Britain from Kenya at great cost, mining is a energy-hungry business. Rarer metals, such as gold and platinum, occur in concentrations as low as 1g per tonne of ore. The additional energy needed to extract and process this ore means mining these metals has a much greater environmental footprint compared to more concentrated metals, such as iron, which is the major constituent of iron ore.

The energy and environmental costs of mining rare metals are no different to the air miles for flying in out-of-season fruit from the other side of the world – and they leave these metals vulnerable to cost spikes due to rising energy costs or environmental legislation.

Vulnerability of supply

It’s possible to substitute fancier ingredients with something more common – student pasta is generally dressed with industrial cheddar rather than parmesan. Manufacturers will similarly find ways to adapt to what’s available in the face of supply restrictions, just as miners will look for fresh deposits in order to take advantage of spiking prices.

Risks to global supply and environmental consequences for 15 rare earth elements. Graedel et al/PNAS

For example the rarer metal cobalt can be substituted by the more common nickel for many uses. But other metals, such as thallium and lead, are chemically very difficult to substitute and possible substitutes are equally rare.

Another consideration is how key the ingredient is to the recipe; it might be possible to leave out a bay leaf, but there’s no coq au vin without the wine. Some metals such as gold and silver are central to world and national economies, whereas others are insignificant.

Where criticality falls down

A systematic approach such as this loses sight of details. For example, the Yale researchers' criticality system flags gold as vulnerable to supply restriction because of its wide use and lack of available substitutes. But only 10% of gold has practical uses in electronics or dentistry, so the remaining 90% largely in bank vaults or jewellery boxes could be put to use if necessary.

Also gold is the most highly recycled metal; nearly all the gold ever mined – an estimated 176,000 tonnes – remains in use. Any shortfall from restricting gold supply can easily be made up from domestic gold sales (“Your gold for cash!”).

Another issue with criticality figures is that they are a snapshot. Due to the delays in reporting figures, the study is based on 2008 statistics that are already out of date. Nor do they anticipate changes in demand – tellurium is determined to be unremarkable, yet it is essential for solar panels and demand is expected to outstrip supply by 2020, potentially bringing an abrupt halt to the roll out of sustainable solar power.

Despite these issues this study presents the most consistent picture we have of threats to metal supply, one that will be of use to industry and governments alike. More vulnerable metals can be the target of measures to reduce use, increase recycling or locate more environmentally friendly or geopolitically benign sources – such as stocking up from the local farm shop.

The cutting-edge science taking on some of the world's most notorious parasitic plants

Can you spot the crop? ShutterStock

Thousands of plant species have adopted a “parasitic” mode of life, living off a host plant which supplies it with water and nutrients. Most of these remain harmless, but a few have evolved to become serious agricultural weeds that threaten food security in some of the world’s poorest regions.

Parasitic plants are deceptively common, you have probably come across the snarling strands of Dodder – a stem parasite which infects nettles – in a local hedgerow. Even the world’s largest flower, Rafflesia arnoldii, found in the rainforests of South-East Asia, is a parasite, infecting and living off tropical vines.

A tropical parasite. ma_suska, CC BY

Plundering reserves

What unites all parasitic plants is their ability to locate a host plant – usually through recognition of specific chemicals – and form an organ called the haustorium. This organ forces its way into the host plant stem or root and allows the parasite to freely withdraw nutrients to fuel its own growth and reproduction, plundering the host’s reserves. When the host in question is an important agricultural crop, this can have devastating consequences for the farmer.

Perhaps the most notorious example of a parasitical weed in agriculture is Striga hermonthica – a root parasite which infects all major cereal crops. Usually found in Sub-Saharan Africa, farmers call it “witchweed” because it has a shrinking effect on the host plant, causing it to be stunted and dramatically reducing yields. As the parasite germinates underground, a farmer will have no idea if his plants are infected until the parasite sends up shoots of delicate (and ironically beautiful) purple flowers. At this point, it is too late and his harvest is doomed.

A beautiful nightmare for cereal farmers. Marco Schmidt, CC BY

Worse still, the land becomes practically useless as Striga seeds can remain dormant for decades to ruin any future harvests. As a result, Striga hermonthica is thought to be the largest biological constraint on cereal production in Sub-Saharan Africa, causing annual losses in the region of US$10 billion.

Suicidal germination

There are few ways to protect crops from parasites such as Striga. One method however, is to induce “suicidal germination” of the parasite seed by treating the soil with host-derived compounds – which induces the seeds to germinate. In the absence of a host, the parasite seeds cannot survive and die, allowing the soil to be sown for crops.

Another strategy is applying herbicides to the seeds of herbicide-resistant crops to prevent the parasite from attaching. Such chemicals, however, are too expensive for subsistence farmers who are left with labour-intensive options such as rotating crops with non-host species and weeding out the emerged parasite shoots by hand.

Biological control may be an alternative; the legume Desmodium uncimatum, for instance, appears to suppress Striga infestations. Curiously, Desmodium also repels another serious pest, the stem borer moth, making it a highly attractive form of natural control.

Breeding the solution

The most effective approach to date has been using naturally resistant crops, carefully selected through traditional plant breeding techniques. In some cases, the resistant host produces lower levels of germination stimulants, whereas in others the parasite is physically prevented from entering the host stem or root.

A problem with these cultivars is that they tend to be found among wild relatives of crop species which also have poor yield. It can take decades to breed parasite-resistant traits into commercial plants using traditional techniques. Genetic engineering is not currently an option as the genes supporting these traits have not been identified. Research groups are currently focused on identifying these resistance genes, so that they can be used to develop “DNA-markers” that can detect resistant plants early and so speed up the breeding progress.

Some of these resistant responses do occur in commercial crops, however an over-reliance on these has triggered the evolution of more virulent parasites and it is a constant race against time to identify new sources of resistance. If enough resistant genes are identified, plant breeders hope to incorporate them in a single crop to provide long term resistance.

Genetic control

Certain research groups have also begun to experiment with “RNA interference” (RNAi) technology. This is based on using short strands of ribonucleic acid – a biological coding material very similar to DNA – that can be used to disrupt expression of genes essential for parasitic plants to function. If the host plant is engineered to express RNAi strands that target parasite genes, then the parasite can be suppressed without any detrimental effect on the host. This has been successful in protecting tomatoes, but not for cereal crops against Striga.

Apart from being huge agricultural pests, researchers study parasitic plants because there’s still so much we don’t know about this fascinating group of plants. For example, we have yet to fully understand how parasites overcome the host immune system or exactly which substances it absorbs from the host plant.

My own research PhD is investigating what defence pathways may underpin resistant responses to Striga gesnerioides – a species closely related to Striga hermonthica but which infects cowpea. It is clear that within my own area of research, besides the field of parasitic plants as a whole, there is more than enough to inspire scientists for many decades to come.

It turns out there's truth to 'dead battery bounce' after all

Some will come out alive, other will not. batteries by Anna Shkolnaya/Shutterstock.com

It sometimes seems as if AA batteries breed when left alone in dark drawers around the house. As children rip them out of toys as they run out of juice the dead ones without charge get mixed up with the new ones. And somehow a working battery tester or multi-meter is never to hand to test them (and may even have had its batteries purloined for use in something else).

One rumoured and simple test to determine a flat battery from a good one is the dead battery bounce – drop them on the floor, and the flat ones bounce. This has been met with a certain degree of scepticism, with many claiming the technique has no scientific basis at all. However, the matter has now been settled with the results of a peer-reviewed study from researchers at Princeton University published in the Journal of Materials Chemistry.

The dead battery bounce

What the study shows is that the more the battery discharges, the greater its bounce – as measured by dropping batteries down plexiglass tubes and recording the height of the bounce. This correlation levels off when half the power has been used. As well as putting doubts over the usefulness of the technique to rest, the authors have also figured out just why the batteries’ properties and tendency to bounce changes as its power is depleted.

Dissecting batteries

Most disposable batteries consist of two chambers. One is the positively charged cathode, which contains manganese dioxide. The other is the negatively charged anode, which contains zinc in the form of a gel, and some potassium hydroxide – the alkali that gives standard, non-rechargeable alkaline batteries their name.

Inside an alkaline battery. Tympanus

When the two ends of a battery are connected, the zinc reacts with the hydroxide in the anode which frees electrons to flow to the manganese dioxide at the cathode, generating electricity. During this process the various chemicals react to form zinc oxide and another form of manganese oxide. When all the zinc has reacted, there is no more to create a flow of electrons, and so the battery goes flat.

The Princeton University team then dissected batteries with various degrees of discharge and examined their contents under a scanning electron microscope. They discovered that in the process of discharging, there also a physical as well as chemical change in the nature of the battery.

The zinc oxide forms around the zinc particles embedded in the gel, slowly turning the gel to a ceramic. While the material starts as tightly packed particles, the oxidisation process forms tiny bridges between them, producing a material a bit like a network of linked springs, which gives it bounce. Anyone who has ever dropped a jelly on the floor will know that gels don’t bounce – but the ceramic mold it’s formed in might.

However, “maximum bounce” is reached when the battery is down to about half its charge, at which point the amount of bounce levels off despite the fact that more zinc oxide is still forming. So the bounce technique can reveal that a battery is not fresh, but it is not an indicator that it’s entirely flat. Still, it’s an easy and instant way of checking the profusion of batteries filling our drawers – no multimeter required.

Where and what is happening in your brain when you sleep?

Dreamtime. Sleep by Shutterstock

Sleep has profound importance in our lives, such that we spend a considerable proportion of our time engaging in it. Sleep enables the body, including the brain, to recover metabolically, but contemporary research has been moving to focus on the active rather than recuperative role that sleep has on our brain and behaviour.

Sleep is composed of several distinct stages. Two of these, slow-wave (or deep) and REM sleep, reflect very different patterns of brain activity, and have been related to different cognitive processes.

Slow-wave sleep is characterised by synchronised activity of neurons in the neo-cortex firing at a slow rate, between 0.5 and three times per second. The neo-cortex comprises the majority of the cerebral cortex in the brain which plays a role in memory, thought, language and consciousness. In contrast during REM sleep, when most of our dreaming happens, neuronal firing is rapid and synchronised at much higher frequencies, between 30 to 80 times per second.

Such patterns of brain activity during REM sleep are reminiscent of those observed during wakefulness, and for this reason REM sleep is often referred to as “paradoxical” sleep.

Cognitive functions

There is growing evidence that slow-wave sleep is related to the consolidation of memory and is involved in transferring information from the hippocampus, which encodes recent experiences, and forging long-term connections within the neo-cortex. REM sleep has been linked to processes involving abstraction and generalisation of experiences, resulting in creative discovery and improved problem solving.

Though there are substantial similarities between wakefulness and REM sleep, numerous studies have explored differences in the activity of brain regions between these states, with the cingulate cortex, hippocampus and amygdala more active during REM sleep than wakefulness. These regions are particularly interesting to cognitive neuroscientists because they are key areas involved in emotional regulation and emotional memory.

However, which sub-regions are active within these broader cortical and limbic areas – the pathways in the brain that produce these patterns of activation – and the precise function of the activity in these regions during REM sleep is currently under-described.

Cortical activity in rats

A new study published in Science Advances studied the physiology and functionality of REM sleep in a group of rats and provides insight into the cortical activity and the sub-cortical pathways that result in this activity. The level of detail of this study provides a major step forward for our understanding of the effect that REM sleep has on our brain and cognitive behaviour.

Rat sleep. Tomi Tapio K, CC BY

The authors studied groups of rats who were allowed to sleep, but prevented from entering REM sleep for three days. Six hours before assessment, half of the rats were allowed to sleep normally, and half continued to be deprived of REM sleep. The rats that were permitted to sleep normally then demonstrated raised levels of REM sleep within those six hours. This enabled a comparison of the effect of recent REM sleep between groups. An additional control group of rats were allowed to sleep normally throughout the study.

Gene expression analysis involves tracking the presence of particular mRNA or proteins that can be identified as the consequences of certain genes operating. The rats who underwent substantial REM sleep before testing were found to demonstrate greater expression of several genes that are associated with syntaptic plasticity (how quickly their synapses can adapt to changes in a local environment) and which affects the efficiency of neural transmission in the hippocampus.

In the neo-cortex, the gene expressions related to how well our synapses adapt also increased following REM sleep, but those related to neural transmission were reduced compared with the group that was prevented from REM sleep. So, the function of REM sleep appears to be due to changes in the way that neurons communicate. This is consistent with the view that REM sleep allows the brain’s memory processing systems to re-balance, which enables effective responses to experiences the next day.

Where in the brain?

Stained neurons from somatosensory cortex in the macaque monkey. Brainmaps.org, CC BY

In a further study, the same group determined the precise location of where these changes actually occur in the brain. In the neo-cortex, there was a general increase in plasticity throughout several areas, including sensorimotor regions that bring together sensory and motor functions. In the hippocampus, it was generally confined to the dentate gyrus, which is thought to contribute to forming new episodic memories among other things. REM sleep was also associated with reduced neuro-transmission throughout many regions of the neo-cortex, indicating that REM sleep likely results in a general weakening of the connections between synapses, which may enable brain networks to better learn from multiple experiences rather than be affected only by single instances.

The claustrum: consolidating emotion and memory. Was a bee

The final studies the group conducted determined the source of the cortical changes in plasticity and neuro-transmission during REM sleep. By tracking signal transmission between different brain areas together with chemical lesioning (in which brain areas are temporarily inactivated), they identified two further areas called the claustrum and the supramammillary nucleus as having key roles during REM sleep.

These two areas have been identified as involved in integrating emotion and memory. The claustrum is a very thin layer of neurons that are found underneath the inner neo-cortex. It is known to link to and from very many regions of this part of the brain. As such, the claustrum has been implicated in integrating stimuli from several senses and is involved in linking areas involved in emotional processing and attention.

The supramammillary nucleus, within the hippocampus, is also known to interconnect to multiple areas of the brain, several of which are associated with emotional processing.

The implications of this work provide converging evidence that REM sleep modulates activation and synaptic processing in areas of the brain that contribute to the processing of emotion. This is also consistent with previously untested accounts that suggest REM sleep is important for encoding memories (but without their emotional content). While the role of dreaming during REM sleep is still yet to be linked to observed effects from neuro-chemicals in the brain, understanding what is happening in our brains when we dream could yet prove to be key to processing of emotion and memory.

Amazon Dash is a first step towards an internet of things that is actually useful

From 1-click to 1-push ordering with Amazon's Dash Button. Amazon

The internet of things has attracted a lot of attention and generated considerable column inches; and yet, despite all the attention, has remained pretty much absent – an internet of vaporware.

Samsung wants to internet-connect all the items in your home and major firms such as Cisco, IBM, and Apple are all keen to get involved in… in whatever it is.

Sometimes “smart” devices have really been about proof of possibility rather than producing any significant improvement in functionality or additional benefit to the consumer.

Finally Amazon, very much a real, non-vaporous company, has produced an internet of things device called the Dash Button. The marketing hype that Amazon is building around Dash goes some way to hiding its mundane nature: while the hand-held Dash device can automatically place orders for household goods by scanning barcodes or through speech recognition, the cut-down Dash Button is a small, push-button fob to keep next to, for example, the washing machine in order to order a single product such as washing powder with a single press. Using the household Wi-Fi network to connect to Amazon’s website, the device places the order and deliver is arranged, with payment and address details already in place as part of the householder’s Amazon Prime account.

Amazon Dash, a wand to order household goods. Amazon

To keep an edge, move quickly

Dash is not necessarily a surprising move for Amazon. This is after all the same e-commerce company that “created” the “1-Click” ordering system and even patented it in the US in 1997 (to great scorn), although the patent was rejected in Europe 14 years later.

As a further weapon in the Amazon armoury that includes competitive pricing, efficient delivery supply chains and huge choice of stock, shrinking the purchasing process to its most simple is an obvious element in Amazon’s competitive advantage. Maintaining that advantage requires the company to have sufficient vision, preparedness and ability to take risks in order to implement new technological developments in a retail context when opportunities arise.

This risk can sometimes bring significant rewards for the company. For example Amazon was quick to respond to the growth of the cloud for business, with its Amazon Web Service now one of the leading cloud computing and storage services – confirming Amazon as a leading technology company, not just a shopfront. On the other hand the Amazon recommendation system Grapevine was also proof that sometimes the company is slow to act, or can miss the market altogether.

A ‘future’ that’s older than you’d think

An internet of things device such as the Dash button is relatively mundane. There have been more ambitious and visionary attempts to simplify grocery shopping in the past. For example LG’s Internet Digital DIOS – the original internet fridge – arrived back in 2000, but the “smart fridge” failed to interest consumers. This proves that the technology has existed for some time but the willingness for consumers to accept this level of automation has taken much longer to evolve.

cheezburger.com

Nor does Dash really represent the full potential for the internet of things in that it still requires human interaction – pressing the button – to place the order. Ultimately, shouldn’t devices automate, not just simplify, such mundane necessities as restocking washing powder? Although technically possible, this degree of automation (a promise of internet fridges) remains a step too far for the majority of consumers and the Dash is the acceptable compromise.

Sometimes the first examples of products demonstrating a new and innovative technology may prove to be beyond the wants and even skills of would-be consumers, or beyond their preparedness to engage with it. More recent devices are certainly more simple and accessible than an internet fridge, and perhaps more commercially viable too. First steps – small steps, but steps nonetheless – towards a more fully-evolved potential. But if you want insight into what the future will look like, just scroll back to the past.

Internet of things devices meant to simplify our lives may end up ruling them instead

Internet of things: a helping hand, or holding us back? gleonhard, CC BY

Technology’s promise of wonderful things in the future stretches from science fiction to science fact: self-driving cars, virtual reality, smart devices such as Google Glass, and the internet of things are designed to make our lives easier and more productive. Certainly inventions of the past century such as the washing machine and combustion engine have brought leisure time to the masses. But will this trend necessarily continue?

On the surface, tech that simplifies hectic modern lives seems a good idea. But we risk spending more of the time freed by these devices designed to free up our time through the growing need to micromanage them. Recall that an early digital technology designed to help us was the continually interrupting Microsoft Office paperclip.

It’s possible that internet-connected domestic devices could turn out to be ill-judged, poorly-designed, short-lived technological fads. But the present trend of devices that require relentless updates and patches driven by security threats and privacy breaches doesn’t make for a utopian-sounding future. Technology growth in the workplace can lead to loss of productivity; taken to the home it could take a bite out of leisure time too.

Terry Gilliam’s futuristic film Brazil was set in a technologically advanced society, yet the future it predicted was dystopic, convoluted and frustrating. Perhaps we’re heading down a similar path in the workplace and home: studies show that after a certain point, the gadgets and appliances we employ absorb more time and effort, showing diminishing marginal returns.

We’re told to change passwords regularly, back up content to the cloud and install the latest software updates. Typically we have many internet-enabled devices already, from computers, phones and tablets to televisions, watches and activity trackers. Cisco predicts that 50 billion things will be connected to the internet in five year’s time. Turning such a colossal number of “dumb” items into “smart”, web-connected devices could become the biggest micro-management headache for billions of users.

Security updates for your internet fridge or web toaster? What happens when one causes it to crash. Once you bought a television, turned it on and it entertained you. These days it could be listening to your private conversations and sharing them with the web. That’s not to say a television that listens is bad – it’s just another concern introduced thanks to this multi-layered technology onion that’s been presented to us.

Internet-connected teapot, anyone? A.cilia, CC BY-SA

Good for some, not necessarily for all

Some smart technologies are designed for and better suited to certain groups, such as the elderly or disabled and their carers. There are genuine, real-world, day-to-day problems for some people that something like Google Glass and an internet-enabled bed could solve. But the problems that affect anything that’s computerised and internet-connected re-appear: patches, updates, backups and security. Once we wore glasses until our prescription ran out and the only update a person applied to their bed was to change the linen for a cleaner version.

Internet of things devices and online accounts are unlikely to take care of themselves. With so many dissimilar devices and no uniformity, managing our personal technological and digital identities could be an onerous task. Much of this will is likely to be managed via smartphones, but our dependence on these tiny computers has already demonstrated negative impacts on certain people. Could we witness a technological version of Dunbar’s Number, which suggests there’s a limit to the number of people we can maintain stable social relationships with? Perhaps we can realistically only manage so many devices and accounts before it gets too much.

Too much choice

Facebook founder Mark Zuckerberg famously explained that he wears the same T-shirt every day to reduce the number of decisions he has to make. Yet technology keeps pushing us towards having to make more decisions: how we respond to emails, which software to use, how to update it, interacting on social media – and that’s before we start getting messages from our internet-enabled bathroom scales telling us to shape up. You only need to watch the weekly episodes of BBC Click or Channel 5’s Gadget Show to see the rapid pace with which technology is moving.

Technological complexity increases – and what reaches the marketplace are essentially unfinished versions of software that is in a perpetual state of beta testing and updating. In a highly-competitive industry, technology companies have realised that even though they cannot legally sell a product with a shelf life, there is little to gain by building them to last as long as the mechanical devices of the last century, where low-tech washing machines, cars and lawn mowers wouldn’t face failures from inexplicable software faults.

Of course some will find their lives improved by robot cleaners, gardeners and washing machines they can speak to via their phone. Others will look to strip away the amount of technology and communication in their lives – as writer William Powers did in his book Hamlet’s Blackberry. The majority of us will probably just be biting off more than we can chew.