Extinction: Evolution and the End of Man. Michael Boulter
to diversify. There are now apes in the warm forests, and other new Families including camels and deer in the shrub. There are also new grasslands, legumes and palms. Evolution continues at a high rate, though as yet, in the Early Miocene, there are few, if any, modern species. They will come later, in the evening, migrating south to the more restricted equatorial latitudes of the modern tropics, and evolving into different groups to populate the cooler forests, wetlands and grasslands of the more temperate regions.
Through the afternoon, temperatures become much lower, the weather much more extreme, the ocean currents developing trends familiar today. The changes are not smooth or simple, but occur as oscillations over different timescales. Present-day changes in weather show that these uncertain variations continue. Around teatime the poles become covered with permanent ice, which slowly spread towards the Equator, developing glaciers and icebergs cooling the oceans. Coldloving mammals grow large woolly coats and take advantage of the new niches in the freezing landscape. They diversify accordingly.
Early hominids first appear around 11 o’clock in the evening, and at 20 minutes to midnight Homo habilis is soon followed by Homo erectus. Neanderthals and then modern humans originate a few minutes before 12 o’clock, depending on your view about the precise time, place and definitions of the species. This happens during the Pleistocene, the period of the ice ages, which began nearly 2,000,000 years ago. The northern hemisphere continents become glaciated at five- to ten-minute intervals for half an hour or so before midnight, the end of our day. But then, at just two seconds to midnight Jesus Christ is born to begin the first millennium of the calendar we record today.
Into the future, no one’s too sure how long our virtual journey will last, how far away that elusive end-point really is. Even the dates I’ve given for the virtual journey so far are debatable, different specialists arguing about them all. But what does seem to be pretty well agreed now is the basic plot of the story. Our Earth really is on this kind of journey. These changes really arc happening.
Our planet isn’t the only part of the system that is following the sequence of origin, expansion, maximum diversity, then finally contraction. Species and groups of species do the same thing. I suspect that man-made institutions like governments and empires, businesses and fashion also follow the same patterns, but I have no data to test that hypothesis. If so, this raises an important universal issue: can all these apparently different systems be following a similar pattern?
But so many different things are influencing the Earth system itself that it’s hard for us to be sure of the full effect of each one. We are just beginning to be able to take those that we recognise together, only just beginning to think of our own role in the system of nature and the many different influences we are making. Can the behaviour of our ancestors building Tirefour Broch 2,100 years ago, or hunting mammals in Alaska 8,000 years ago, be seen as part of the same evolutionary process that I’ve painted for the last 6c million years? Even more basically, can the human mind, from our position inside the system, have the ability to interpret these complex patterns and explain the way life works on the whole Earth?
Challenges for a young research group
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