Читать книгу Extinction: Evolution and the End of Man - Michael Boulter - Страница 8

I think answers to this question will come from the interdisciplinary revolution that’s only just beginning. Coincidentally, information technology is making it possible to join together data from different disciplines. What is starting to happen for the first time is clearly shown in the composition of my research group. I’m a fifty-nine-year-old paleontologist, working with two thirty-year-old computer buffs with pony-tails, a young woman who knows more about biodiversity websites than anyone else, and Dilshat Hewzulla, a young mathematician from China who’s a genius at analysing large datascts.

We’re all from different backgrounds, working on the same problem: the changes in biology and environment through geological time. We all have very different knowledge, different skills, and different tolerances of computing. We are all totally dependent on one another. It’s unlikely that our group could happen in a large mainstream university department because all we have in common is individuality and eccentricity. We came together by accident rather than design, yet these oddities bind us together.

Dilshat has introduced to our group another young computer scientist from Urumqi, Alim Ahat, a mathematics graduate and director of a new software company in that city, Ugarsoft. It’s the leading computer company in Xinjiang, a province of China with 56 million inhabitants. There is also my old colleague and friend Richard Hubbard, who cycles round London wearing sandals, brightly coloured trousers that he makes himself, an Aertex shirt and keys around his neck. Whenever the hot nights of the Proms were televised it was usual to see him standing in the front row. At Oxford he studied chemistry, then archeology at London, and now he has an international reputation for performing principal components analysis on our paleontological data.

We work together in a simple and logical way, each taking responsibility for our own expertise and all coming together at the end to use our different perspectives and common sense to make an interpretation. 1 start off the process by finding new data from the scientific literature or the internet. That is then validated, cleaned up and cropped, maybe as much as half being thrown away. As I will keep mentioning in this book, the fossil record is notoriously poor, with gaps, uncertainties and much that is plainly incorrect. Mathematics and statistics help sort it out. Others in the group assemble the cleaner data into spreadsheets, write programs to compare them with things searched from other databases, and compile methods to analyse and model. You can see some of this work at http://www.biodiversity.org.uk

The changes in information technology and data availability arc happening so quickly that we come to accept a danger that the work will be out of date before it’s finished. Another challenge is our bid to compare and integrate data and concepts from mathematics, physics, chemistry, genetics, evolutionary and systematic biology, and cognitive psychology. This is bound to lead to new ways of thinking about what environmental and evolutionary processes do when they are at work on our planet.

This holistic view shows us what lies between the extremes of physical and biological change and teaches us that physics and biology work very differently. One has Laws, the other doesn’t. One can be described quantitatively, the other qualitatively. A question is whether these extremes can be compared, whether physics and biology can be understood and described in the same way. This is more than a semantic issue, because we need some way to monitor and conserve the changes humans arc inflicting on the stock of nature. I fear that the loss in biodiversity, whether it be ecological, botanical, zoological or genetic, seems to be inevitable, whether we count it or not.

The word ‘biodiversity’ sprang into use from the ‘National Forum on BioDiversity’ organised by the US Academy of Sciences in 1986. It was a major topic title at the 1992 Rio Congress which begat ‘Riodiversity’ and more reasonably, biodiversity. It is an interdisciplinary concept, enabling comparisons of previously separate ideas, a new way of thinking about biological systems. The biggest records of changes in biodiversity come from Europe and give an idea of how the problems of loss are being approached by scientists, industry and politicians. Last century, Europe lost most of its sea mammals, natural forests, grasslands and many other habitats and species. Other losses are high when measured in terms of local abundance, but the same species show relatively little change when expressed as regional diversity. It all depends on how you present the figures. I prefer to rely a little on feelings and my common sense.

Another quantitative estimate of the new century makes a chilling comparison to this European observation. It comes from a recent study of ‘Who will feed China?’, where 1.2 billion people now live, and makes cheeky comparisons between East and West. If every Chinese ate just one extra grain-fed chicken a year, that would account for Canada’s annual grain harvest. If Chinese used motor cars the way Americans do, global oil output and CO₂ pollution would both be more than doubled.

But the huge complexity of what’s going on does lead some of us to broader views of evolutionary processes, helping us to better understand the living systems on our whole planet. From the stimulus of the 1992 UN Convention on Biological Diversity, now ratified by over a hundred countries, these factors spread over into groups asking far-reaching questions concerning what science can do to help. One major job is to monitor biodiversity. Another is to educate the global population to respect the planet. Geneticists and pharmacologists are busy defining and extracting beneficial chemicals from threatened plants and animals. Researchers in agriculture and horticulture need the full genetic stock to breed new varieties. Scientists can also advise politicians and administrators and global companies, but usually these people don’t want to listen.

Monitoring this delicate biodiversity and keeping track of disappearing species from different places is proving to be harder to organise than you would think. Just after the Rio Convention several national and international groups began to plan monitoring projects. The first, Species 2ooo, began in the mid-1990s and aimed by that date to link together lists of all known animal and plant species. Our plan was to make internet links to the world’s authoritative biodiversity databases. We attracted the involvement of fish specialists in the Philippines, the insect group at the Smithsonian Institution in Washington DC, viruses in Tokyo, legumes in Southampton and fossils with my group. David Gee, one of the pony-tailed anoraks in my group, devised a program to query these at once, from one request. You can do this now from http://www.species2000.org.

But after five years’ work, the target is still very far off. Species 2000 and other projects have involved a lot of talking, a lot of travelling around the world going to meetings, and a lot of disagreement about which standards to use. They also got caught in a Catch-2 2 situation, which may mean that they can never succeed. The scientists involved believe strongly in precise objective monitoring; because that’s so slow and expensive, nothing happens very quickly. When private-sector money is offered, the condition is for fast results and common names, none of the precision of whether it is one species or another. Most scientists run away from this kind of thing, scared of the commercial sector and of not winning a good reputation in the one they know.

One monitoring project that does seem to be working began long before the Rio Conference. It’s run by UNESCO’s conservation group and is called ‘Man and the Biosphere’, MAB. The programme has devised an international system to conserve particular biosphere reserves, natural areas with animals and plants that can be sustained. Now there are 368 such areas, in 91 countries, and the number is growing. They are selected, monitored and maintained by a whole variety of environmental groups and agencies. In the UK, some are rather formal government committees, others anorak-clad bird watchers, and all contribute to a huge database (www.biodiversity.org.uk).

Another approach to monitoring biodiversity has been formulated by a group of scientists from Oxford and Washington DC. They have identified a number of hotspots, parts of the world with high diversity in exceptional danger of loss. Hotspots such as those around the Mediterranean are estimated to contain 44 per cent of the world’s 300,000 known vascular plant species and 35 per cent of the total known species of mammals (4,809 species in the hotspots), birds (9,881), reptiles (7,828) and amphibians (4,780). But how can we monitor these very sensitive places and police them for restoration to even something approaching their former state?

Data like those from these hotspots are accumulating at an increasing rate. Money and expertise are coming from national and international agencies to survey the biodiversity of these special regions and make it available publicly. These early schemes are scattered around different agencies and have different standards and objectives, but eventually they will come together. The internet will see to that. During the Rio Conference it was clear there wasn’t enough information to support the arguments of gloom and doom that were being expressed publicly. Now the situation is quite different, though a lot more has to be done. Around the time of the Rio meeting, my own research group started to build databases of where fossils were found, not realising where the work was going to lead. We thought we were making a catalogue of species, detailing their geological age and where they have been found. It’s still far from complete.

Instead, our energies have taken us into the very different world of data analysis, the mathematics of complex systems and to the edge of chaos theory. Our approach is to standardise all the data into the same format, with separate Microsoft Excel columns for names, ages, location, ecosystem and other variables. To make sense of the incredible amounts of such data, we propose models against which to test those data. If we think biodiversity is changing in a particular way, we describe that way with a mathematical equation and see if the data can fit it. We test to discover if there are any broad trends showing up to conform to the model. To our great surprise the patterns that are emerging from our analysis of records of extinct plants and animals are clear and definite, and our scientific results confirm our right to be very worried about what is happening to life on our planet.

We have found consistent patterns in these evolutionary changes, in groups of animals that are extinct, and in others that survive. The changes follow a simple model that can be expressed as a mathematical equation, and we use this to predict likely trends in evolutionary change. It’s rather like how weather forecasters accumulate data from earlier records of location, temperature, wind and pressure. The patterns are then used to calculate how the values will go forwards in time, and separate statistical methods give a reasonable amount of certainty. We have been doing something very similar working from our evolutionary patterns, and it’s now very clear that there is sudden and unexpected interference in the patterns: the environmental changes caused by man.

Darwin’s mentor, Charles Lyell, was one of the first geologists and is best remembered today for his maxim ‘the present is the key to the past’. This principle urges geologists to interpret ancient structures by observing the way things happen in the present. I fear this oversimplification has misguided many innocent students of geology, as journalistic phrases often do. I will argue in this book for another way to explain the urgent crisis for biodiversity. This is by inverting Lyell’s phrase to become the past is the key to the present. That’s what our article was all about, the one Dilshat’s e-mail to Taiwan told me had been accepted for publication: computer modelling from fossil data. This paper works more subjectively than most modern evolutionary theory. That is one reason why the work is so controversial. In it we interpret evolutionary patterns in the fossil record with the statistics and mathematics of complex systems and chaos theory. As I will explain in chapter 3, we compare our results with those from three other well-worked sets of data: one set derived from purely random processes, a second from artificial sources, and the third from natural ones. Our results have the same pattern as those from the third system. Nature, we argue, is in control of itself: biological evolution is controlled from within that system of life on Earth.

Our analysis encourages a different way of looking at the large datasets of biological information from all the different disciplines now being brought together. It takes us away from the search for laws, precise definitions and quantitative testing. Instead, it leads us back into the state of mind where we worked with mystery and uncertainty, accepting that we cannot explain everything in detail. The systems of life in the diverse and changing environments on this planet are so complex that only subjective methods can assess them now. Scientists need to accept life’s beauty, and work with it like a fairy story, changing the focus to fit the particular needs of the particular circumstances at different times. Narratives change. In the past science has often responded to what it knew by telling stories about the world and finding the facts to confirm them. Today, the facts are telling a new story, less welcome than some of the earlier ones, and with an ending that we may not be able to change.