Editor's pick: Not a plastic thing but a conspiracy
The thing that defeated a Go grandmaster was not a machine – a contraption of metal and plastic – but a conspiracy of all known previous grandmasters, ably helped by a similar conspiracy of experts in computer programming (19 March, p 5 and p 9). Seen this way, such a defeat was unavoidable in the nature of games. Perhaps more generally such situations are unavoidable in the nature of human cooperation.
The moral is not that we should now try to design games that will defeat these imagined enemies, nor that we should freeze in horror at the thought of what they may get up to next. It is that we should put our powers of cooperation to better use in trying to deal with the dangers of our actual situation, which are perfectly real.
Newcastle upon Tyne, UK
The editor writes:
• A conspiracy of grandmasters is the starting point – but the result is a machine that makes . Humans master Go by learning patterns of play; AlphaGo has no such constraints and came up with several entirely new approaches to the game.
Even mice are smarter than our AI
Hal Hodson reports on a debate about whether artificial intelligence will eventually exceed human intelligence (26 March, p 23). This presumes that artificial intelligence currently lags behind and is gaining on human intelligence.
In reality, artificial intelligence hasn't even reached the starting blocks. Existing systems are interesting and sometimes useful, but not even minimally intelligent. Even a mouse might attempt to climb out of the maze – a sign of independent decision-making and intelligence. Watson would never get bored of answering questions on the TV show Jeopardy and AlphaGo would never decide to read a book instead of playing Go. The time to start debating AI versus human intelligence is after we have created artificial intelligence.
First class post
SETI has only listened for 30 years… to around 200 stars: give it a break!
Louise Fazlagic for the search for extraterrestrial intelligence around red dwarf stars (9 April, p 7).
A Turing test for prosthetic limbs
I am constantly amazed by the most recent developments in prostheses: Helen Thomson now reports a bionic finger that can feel textures (12 March, p 12). I propose that the ultimate test for a prosthetic hand would be for the user to try to find a particular object in their pocket – the prosthetic would need to deliver enough information to discern coins, keys, lighters and paper notes. As in a Turing test, the device passes if its performance is indistinguishable from that of its biological equivalent. I suspect that mechanical prosthetics are still nowhere near this.
Given that biological tissues currently offer the pinnacle of sensory perception, perhaps we could attempt to develop biological prosthetics. Could this help prevent rejection, and could it help deal with the loss of connectivity that plagues the junction of hardware prosthetics with biology?
The trouble with infinity in circles
You published a diagram claiming that when using rectangles to approximate a unit diameter circle, the total perimeter is four, unless you use infinitely many rectangles, in which case the total is pi (19 March, p 37). The first part of that claim is true, but the second is clearly false. Since the midpoints of the sides of the rectangles are never tangent to the circle (except at the ends of two perpendicular diameters), the total perimeter will always be four.
If you approximate the circle with a regular polygon whose sides are all tangent to the circle, then as the number of sides tends to infinity, the perimeter of the polygon will converge to pi.
Cambridge, UK
The editor writes:
• The point we were trying to make was precisely that using sequences of finite objects to approximate an infinite one can have serious pitfalls – though we could have made that clearer.
Fish species split before our eyes
Michael Le Page reports on three-spine sticklebacks in Switzerland's Lake Constance embarking on the path to speciation (5 March, p 14). Anyone who has fished for tiger fish (Hydrocynus forskahlii) on Lake Kariba in Zimbabwe will be very familiar with this. There are long, thin tiger fish in the Zambezi river and shorter, fat ones in the lake itself. A simple explanation would be that the plumper fish find it harder to fight the strong currents in the river, so tend to get washed out into the lake, where currents are more diffuse. The slender fish are more streamlined and can hold their position in the river. It may well be that the same process is operating in Lake Constance. Over time this may lead to separate breeding colonies, and consequent genetic diversity.
Climate change and changing land use
Surely the solution to carbon storage is far simpler than Fred Pearce suggests (20 February, p 30). He makes the assumption that land use for farming will stay the same.
Livestock farming uses roughly a third of the land mass. Because of the contribution this makes to greenhouse gas emissions, a recent concluded that it is unlikely that global temperature rises can be kept below 2 °C without a radical shift in meat and dairy consumption. Rather than creating vast monocultures of fast-growing trees or blankets of algae (that might well have their own detrimental effects), I wonder how much carbon emission could be saved if more people in developed countries ate less meat.
Don't demonise pine martens
The portrait of a pine marten by Terry Whittaker was splendid (19 March, p 25). But I was disappointed that you described the species as “one of Scotland's most voracious predators”.
Such language reinforces 19th-century attitudes to certain predators that still prevail on many game-shooting estates. These are associated with widespread illegal persecution of a number of rare and threatened species. is neither more nor less voracious a predator than, say, a blue tit.
A chicken farmer is not at all surprised
You report another observation of male-to-male necrophilia in birds (5 March, p 18). Any chicken farm operator will have seen this many times.
Sexually active cockerels queue to mate with recently deceased birds. Injured chickens also suffer unwanted attention from male birds, presumably due to the posture they adopt.
Part of the job involves rapid removal of unwell birds, for welfare reasons and to prevent males wasting valuable sperm.
Electricity supply still needs grids
Aviva Rutkin writes that the firm Transactive Grid aims to trade electricity between consumers on President Street in Brooklyn using the digital blockchain protocol, which means it will no longer be possible for a consumer who buys electricity not to pay the person who sells it, so electrical utility companies would no longer be needed (12 March, p 22). The article concludes that the only problem to be overcome in rolling out this scheme is “the might of the utility companies”.
It would seem that another problem is the role the utility plays in keeping consumers supplied with electricity when the sun goes down and on cloudy days. The utility just might insist on being paid for the wires it installed, and for the power stations which make this supply of electricity possible.
How to measure the refugee crisis?
Given the continuing coverage of migrant crises (9 April, p 29), and more occasional coverage of the economic importance of the arms industry, further thought could be given to representing the linkage between the two. A measure of refugees per kiloton (RPK) might record the number of refugees from a country per kiloton of explosive to which it is exposed.
This statistical innovation could also provide a connection between the role of countries engaging in bombardment and the numbers of incoming refugees. It may even focus debate on an equivalent to the “polluter pays” principle: “bomber pays” reframes financial responsibility for the integration of refugees.
Chaos, capitalism and planning
You quote Yonathan Parienti, who wants a system for online activists to put their money where their click is, saying: “Remove capitalism and you have chaos. We want to make it better without turning to radicalism” (12 March, p 20). I assume Parienti meant “disorder”, not “chaos” in the strict sense. And this point of view contrasts with many of your regular contributors on the problems facing humanity.
If we hope to continue with any sort of ordered existence, then the laissez-faire policy of the past three or four centuries is clearly going to have to stop. More and more we shall need to give careful consideration to the exploitation of Earth's limited resources.
Production simply for profit needs to be replaced very soon by production for basic needs. How humanity finishes off its dwindling resources will need management according to internationally agreed protocols.
For the record
• Oh spawn it! Many people have in fact persuaded corals to breed in captivity (February, p 42).
• The geological feature associated with the demise of the dinosaurs consists of clay a few centimetres thick; a sub-layer a few millimetres thick is strongly enriched in the element iridium, compared with the rest of Earth (2 April, p 8).