This Easter I spent a fair bit of time in the “Great British countryside”. From the Pembrokeshire coast in South Wales, to Lizard Point in Cornwall. But whilst walking along picturesque coastal paths from one outcrop (Geology feild trip) to the next I had a fair amount of time to let my mind wander. I grew up in the countryside and for all my life I have considered everything about the countryside quintessentially British, unspoilt, and natural. Large swathes of land quite distinct from the bustle of the city, for which I believed it was our duty to protect and conserve.
Many people share this view, hence why there is always so much uproar when new airports, roads or fracking is proposed; those filthy politicians always trying to tarnish our countryside. Right?
I realised last week whilst gingerly stepping over cow pats and hopping over styles, that there is simply nothing remotely natural about natural England. Every aspect of our landscape has been crafted by us and our ancestors before us. No area of Britain has escaped. Heather shouldn’t grow on hill tops, grass shouldn’t carpet the landscape. Deformed bovines with swollen udders and emasculated mouflon (the ancestors of sheep apparently) with ridiculous white puffy hair shouldn’t even survive. Why is the national bird of India, the peacock undeniably more well-known and common in ‘wild’ Britain than (the formally) native Great Bustard. A What? Yes, precisely…
Our ancestors have been altering the Earth for at least 400,000 years, since controlled fire was first used to clear the Savannah. Although the biggest change to the ecology of the Earth in millions of years (since the last ice age) began with the emergence of agriculture in the Middle East 7000 years ago.
Before this time, almost the entirety of Britain – and Europe – was covered in dense forest, such as what survives today in a few pockets of Central Europe. Bears and wolves of course limited the populations of herbivores, which we know in Ireland at least contained Giant Elk, with antlers up to 12ft long. The story is similar elsewhere. Recent findings, and re-interpretations of the writings of some of the earliest explorers, indicate even the most virgin of virgin rainforest in the Amazon basin is an anthropological artefact.
Research by Clark Erickson of the University of Pennsylvania found tens of thousands of km of raised banks across the Bolivian Amazon that he believes were dug by humans. He claims, “By corrugating the flooded fields, farmers created ridges on which they could plant their crops, clear of the floodwaters and also of highland frosts, while also collecting water for irrigation in the dry season. It was a flatland equivalent of the ancient practice of terracing hillsides. The digging and earth-moving involved in creating these structures, is comparable to building the pyramids. They completely altered the landscape.”
Erickson also stumbled on something else: a vast system—estimated to cover 500 square km’s—of fish ponds and weirs, which captured the fish in the wet season, to eat during the dry. They were fish-farming on the edge of the rainforest. These fish ponds and raised fields stretching across the plains for thousands of square km’s could have sustained maybe a million people. Buried charcoal in the roads and mounds suggests that they were created up to 2,000 years ago.
An Early Spanish on expedition to Baures, Bolivia in 1617, described entering towns along causeways that could take four riders abreast. The records of the explorer Jesuit confirm this and suggest that some islands and causeways remained in use into the eighteenth century. It is likely that the once flourishing people of Baures were devastated by famine or disease, and subsequently nature has retaken what was once hers, capitalising on the rich soils left behind, resulting in the diverse biodiversity that we see today.
The point here is that what we consider to be nature is prejudiced by what we consider to be the norm. The amazon, it appears, is no more natural than Cambridge fens which were long ago drained to farmland. However, true nature doesn’t care for fences or boarders, and when given the chance it will take bounce back, although not always in the same way.
To illustrate my point, today is the 27th anniversary of the Chernobyl disaster, and this is what the abandoned town of Pripyat looks like now:
- Chernobyl, 27 years on, now an eden for wildlife.
- The exclusion zone (approx. 3000 km2) has paradoxically become a unique sanctuary for biodiversity. The evacuation put an end to industrialisation, deforestation, cultivation and other human intrusions, making it one of Ukraine’s environmentally cleanest regions – except of course for the radioactivity. Beavers, deer, wolves, lynx, as well as rare birds such as black storks and azure tits have all moved in. The rare white-tailed eagle now thrives in the area, and Europe’s last remaining mega-fauna, the Przewalski horse and the European Bison have been introduced successfully. Suprisingly studies on voles have shown that the still existing high levels of radioactivity do not have any genetic (or physical) abnormalities.
- It appears ‘Nature’ is just somewhere where humans aren’t. Mega cities might be the green solution.
The threats of ‘Global Warming’ ‘Climate Change’ have been drilled into us to such an extent that it appears we are become immune to them, in fact instead of addressing the issues, we are ever more comfortable turning a blind, obnoxious, eye. Today the World Bank has released the latest report warning of the devastating effects of a predicted 4oC rise in mean global temperatures over the next century. So what, we heard that before, and we are all still alive right? Let’s continue driving our 4X4’s and drilling for oil, and we will work out some way of dealing with it later. In any case, cold old England could do with a nicer, warmer summer.
The fact that this report has failed to make it into the headlines is worrying. Instead of warning us that ‘we’re on track for a 4°C warmer world marked by extreme heat-waves, declining global food stocks, loss of ecosystems and biodiversity, and life-threatening sea level rise’, PM time-wasting welsh income tax, tube strikes have made it onto the BBC homepage today. In august this year, on the day that it was announced that artic sea ice has reached an unprecedented low level, three weeks before the average annual minimum, the argument about where the new runway should be built filled the media. The question of should another runway even be built was not even considered. The recent American election was taken to a standstill by a freak tropical storm, most likely of higher intensity due to the effects of climate change on ocean currents. Yet as they recover from Sandy, the US is pledging to increase the oil industry substantially over the next decade.
Read the report (http://climatechange.worldbank.org/content/climate-change-report-warns-dramatically-warmer-world-century ) it’s scary. Look at the figures released by the IPCC regarding the observed effects of climate change that we can see right now. Even more scary. The raw data is undeniable. The predictions of course cannot be perfect, but these are the accumulation of almost 30 years of climate science to date. We should be taking notice.
Take a minute to browse the environment section of the Guardian or journals such as Nature. Reports and studies demonstrating the decline of animal species come in by the day. Today for example the guardian reports that Britain’s bird population has decreased by 44 million since 1966.
What is concerning is that all these figures, warnings and predictions are now so commonplace, that it seems we are becoming immune to them. I urge you to take a step back, really think about it and read the report as if you have never heard about climate change before. If asked by your grandchildren, “you knew about climate change, so what did you do”? I for one want don’t want to say ‘nothing’.
Tomorrow I begin my Ecology 1b project, with the aim of answering the question: ‘Is there a link between higher atmospheric carbon dioxide levels and the growth rate in ash trees?’
I admit that on the outset this does not seem like the most enthralling of projects, but here I will attempt to justify why it is in fact ‘quite interesting’.
Firstly, all recorded data suggests that CO2 levels have soared since the industrial revolution.
Worldwide, trees are incredibly important for carbon sequestration – eg taking CO2 out of the atmosphere, and storing in tree trunks. Plant more trees; store more carbon - It would seem.
We can also model how much CO2 we could remove from the atmosphere through the planting (or the prevention of destruction) of certain trees.
However, we believe that in order to improve these models, we need to find out how the growth rate of trees (and hence carbon storage) changes with increased/decreased CO2.
We will test this hypothesis on Ash, as these fast growing trees are readily available to core in our location. If we find a significant correlation in Ash then it would be important to test other species, especially ones which are currently used in climate models as sources of carbon storage.
As a side to our main study we will also look for general correlations in our tree core data. In 1987 there was a big storm that felled many ancient (and dominant) trees in Surrey. We will check the core data to see if this event is recorded in the subsequent growth rate of surviving trees. Perhaps with more space, and less competition, the growth rate of Ash increased in this location in the Surrey hills.
Lets see how it goes…
A few days ago, we received the sad news from the Charles Darwin Research Station in the Galapagos Islands that Lonesome George has passed away.
It appears the last act of the sole survivor of Chelonoidis nigra abingdoni, (a subspecies of giant land tortoise) was to trend on twitter; a feat certainly unique in the tortoise world, and most likely never to be repeated again.
It was a testament to George, who died at about 100 years old that not only the conservation world, but the wider public acknowledged his passing. To many he was the symbol of conservation. To others a relic of evolutionary history. For it was Giant tortoises like George that inspired the young Darwin on his travels to the Galapagos. Each sub-species adapted to different niches within each island – the fingerprint of an adaptive radiation in response to natural selection.
Scientists back in the 1970′s thought that the Chelonoidis nigra abingdoni lineage was already long gone. They were surprised when they found George wandering on the small island of Pinta alone (hence the name). In the decades since, they’ve tried, in vain, to find a female of the same subspecies for him. Their efforts, it probably goes without saying, were unsuccessful. Still, they tried to continue George’s ancestral line, even if they couldn’t guarantee his subspecies. They penned him with two females from a closely related sub species, genetically similar enough they hoped, and waited to see what might happen. They celebrated when eggs were produced, but alas, none of them hatched. George, it seemed, was destined to remain the rarest creature on the planet, despite the Research Station’s best efforts.
Most probably George’s ancestors were wiped out by European colonisers for their meat. Unfortunately the trend continues, and many of the world’s tortoises are in trouble:
- Ploughshare tortoises have their shells defaced to make them worthless on the black market. There are only a few hundred left in the wild and they are critically endangered.
- Poachers known as “the tortoise mafia” and locals who eat tortoise meat threaten Madagascar’s rare tortoises, which include the Ploughshare, Spider, Radiated and Flat-tailed species.
- Burmese starred tortoises are also listed as critically endangered on the IUCN Red List. They get their name from the striking yellow and dark brown star pattern on their shells.
Lonesome George became part of the Galapagos National Park breeding programme, and despite the failure to produce fertile offspring, his genes will be preserved. Artificial fertilisation may yet provide a route to maintain his unique gene pool.
A fellow student of mine, Olivia Green, recently visited George and all the Galapagos islands. She discovered that although there is a heavy tourist influence, the place is not trashed. In fact some 20,000 giant tortoises of other subspecies still live on the Galapagos. Perhaps the haven which inspired Darwin can now also inspire us as a model of conservation in the modern world – treading the fine line between publicity, tourism, and the maintenance of a pristine environment along with its inhabitants.
A comment on the BBC News article reads “Species going extinct is part of the evolutionary process including those affected by other species including man…we are just part of the planets eco system” If anyone reading this does not feel saddened by this view, then I feel sadden for you.
We are not passive entities in the processes driving extinctions on our planet. We as a species cause the destruction, but we can also prevent it. But the lesson I think we can learn from Lonesome George is that extinction is also fickle. Despite the best efforts of the world’s leading conservation experts and the universal appreciation of his plight, the figurehead of conservation could not be saved. This does not mean that conservation is doomed, but it is an eye opener and reminds us that public awareness about endangered species does not equal saving them.
Conservation must shift its position from a charity case to an economic necessity. Post cards from the Galapagos in return for a donation may make us feel good inside, but in reality, as proved by George, the charitable approach to conservation is not sustainable.
This is how you can ‘win’ the dating game - basically by being a mathmo’.
Research http://www.bluesci.org/?p=6998#more-6998 tells us that after a given number of social interactions (the learning phase) with members of the opposite sex we tend to assign ourselves a ranking. This ranking is relative to those that we have met, therefore rankings will not necessarily regard people like Angelina Jolie, unless you have been very lucky.
This has parallels to the ‘score out of 10 rating system’. You might well consider the most attractive person in your lecture theatre a solid 9 at the time. Transport yourself to Beverly Hills (or wherever Megan fox and Angelina Jolie hang out) and that rating is pretty sure going to be lowered accordingly; along with your own, unless you really do back yourself.
Right, so you have a ranking. How can you maximise your chances in the most efficient way.
1 – Be speedy, and meet as many people as possible.
A high turnover rate is apparently the key to success. This is given that everyone else that you are interacting with is doing the rating for you. The rating system doesn’t lie. Don’t spend ages worrying about the rank of your potential mate; they will do that for you.
2 – Play the Percentages.
Todd and Miller applied a well-known system of hypothetical decision-making called the “secretary problem” to dating. In this situation, a person must pick the best secretary from a group of applicants who appear in random order, drawn from a pool whose quality is not known. Once rejected, applicants cannot be recalled. It’s all about moving forward and making smart choices.
The solution involves remembering the best ‘applicant’, and then picking the next person who is even better. In this case an applicant is anyone who is interested in you – anyone who accepts an invitation for a date for example, but is within 25% of your own ranking.
So, what’s the magic number? In the secretary problem, the ideal percentage for sampling is 37% of a pool of 100 applicants. That means it would make sense to initially sample 37 people, remember the best of the best, and then pick the next candidate who meets or exceeds that standard.
Despite there being a few more than 100 single people in the world, it is probably unlikely that you would have the time (or money) take as many as 37 out on a date in a short space of time. Thankfully, according to their research, in a group of 1,000 potential mates, only 1 to 2 percent needs to be sampled.
Therefore, the plan for quick success is as follows:
Be realistic. Date at least 10 potential partners. Remember the best of them, and when you find someone equal to or better than, stick with that.
(Be warned though – it’s probably dangerous taking advice from guys that do mathematical modelling, and worse, those that write blogs)
After sitting through a lecture given on primate sociality, I began to consider just how different are we than our primate cousins when attempting to get laid? Are we just Chimps in Chinos?
The image proposed spectacularly by Disney, of the happy husband and wife Mufasa and Sedibi, distributing a strict moral code across the African plains, remains unfortunately, a fantasy. Most animals do not find love and pair up for life. The magnificent colours worn by the mallard drake, is most probably not to impress his ‘wife’ but more the young mistresses further down the river. In fact monogamy (staying with a single life partner) is extremely rare in the natural world, with only 5% of mammalian species being instinctively faithful.
Most animals are promiscuous, and from an evolutionary perspective that makes sense. Males can produce energetically cheap sperm, and it is in not too much of a hassle to ‘donate’ this to a willing female. Therefore a male can theoretically mate with as many females as he meets in his lifetime. In this scenario, the most successful males will be those that are the most promiscuous.
A female on the other hand, has to produce energetically high cost eggs, and invest considerably much more time and energy into pregnancy and the raising of her young. She therefore has a limited number of offspring that she could possibly produce in a lifetime. Therefore, to ensure her genes have the best chance of surviving into future generations she should be picky, and only mate with the physically fittest and most attractive males – for if he is attractive it his likely her sons will be too, ensuring the safe passage of her genes into future generations.
Given this ‘female choice’, not all the males will be chosen; only the most attractive will get to mate. This would then lead to males competing amongst each other to prove their worth – perhaps displaying a huge, vividly coloured tail with a million spots, or baby blue sports blazer on a night out. Whilst the Australian bowerbird is judged on his nest making abilities http://www.youtube.com/watch?v=GPbWJPsBPdA perhaps our inherent appreciation of sport is rooted in an ancient mating display.
All sexual organisms are under the same pressures to reproduce and ensure the survival of their offspring. Depending on environmental conditions, and the behaviours of other individuals within the species, alternative mating strategies may result.
In primates we see that when food sources are spread out and clumped, females tend to congregate in small stable groups, as to monopolise the resource, increase foraging efficiency and reduce the threat of predation. Often the female groups will be closely related, so juvenile males tend to leave, forming bachelor groups until they get lucky with the girls (in chimps however the females leave the natal group).
At this point I would like to make amusing parallels to our infamous ‘laddish’ behaviour. Is a trip to the pub not just an elaborate way of young males announcing their arrival to sexual maturity? Boisterous behaviour, and necking pints may serve to strengthen social bonds, but it is usually so raucous that it will not go unnoticed by any female in the proximity.
If there is limited availability for fertile females, due to long gestation periods, there will be intense male-male competition. Sexual dimorphism will result as only the biggest and most dominate males will get to breed with their harem of females. This ‘polygamous’ behaviour is perhaps best demonstrated by the huge silverback gorillas.
However, we like chimps, do not differ greatly in size between the sexes. In our closest relatives this is due their complex social groups, in which many individuals mate casually and frequently with another. As a result, male chimps have much larger testes in relative to male gorillas. This is because a male chimp will have to compete with other males who are also mating with his girls. Producing more sperm gives him a better chance of being a successful father.
Close comparison of our own genitalia in relation to other apes suggests that we too have a promiscuous past. We fit somewhere in between chimps and gorillas in terms of testes size, which predicts that a series of short term partners was probably the norm in early hominids. Another distinctive feature of human anatomy not shared amongst other apes is the occurrence of concealed ovulation in females. Female chimps – like other mammals – make it very clear as to when they are receptive – meaning males close by get pretty rowdy, and so she is very likely to become successfully impregnated. The males on the other hand, ‘realise’ that there is a low chance that the baby will actually be his, so the potential gains to his fitness by giving paternal care is outweighed by the costs of doing so – the cost being the loss of the opportunity to mate with other females. Mothers have babies, fathers have maybes. So the fathers leave.
However, given that it takes roughly a modern couple 3 to 4 months of ‘trying’ to actually conceive, an early male of our species that adopted the tactic of a chimp would not be likely to leave many descendants. In fact the most successful strategy would be to stay with the same female for 3 to 4 months until she becomes pregnant. At this stage the male is probably most likely to move on and try his luck somewhere else – sound familiar? Do not be fooled by images of muscular cave men fighting of huge monsters with their bear hand to protect a cowering wife and child. The earliest women were more than capable surviving as single parents. In fact evidence suggests that in fact foraging mothers produced most of the food for the clan not the ‘heroic’ mammoth hunting men.
An interesting point is that with the development of concealed ovulation, for the first time in primate history perhaps males had to invent ways to keep his women entertained. Rather than be won over by brutish strength, perhaps an early women chose her partners based on who she could possibly put up with for 3 to 4 months at a time. If this coincided with the emergence of language, could it be that the wittiest or the most romantic males were the most successful with the ladies? Could the human brain have evolved to its unique size not based on problem solving, but due to sexual selection, with the best minds winning ‘the game’? As a currently single natural scientist, with better words than abs, I would love to think so.
Three almost complete skeletons of a huge feathered dinosaur have been unearthed in north-eastern China. The new species has been named as ‘Yutyrannus huali’ meaning “beautiful feathered tyrant” and it is thought that it is a distant relative of the infamous Tyrannosaurus Rex.
Importantly, it is by far the largest feathered dinosaur ever to have been discovered. The paper, published in Nature, raises intriguing questions as to why some of these scaly reptiles developed this ‘fuzzy down’ like plumage typical of a newly hatched duckling.
The fossils include part of the Yutyrannus tail and, crucially, its skull. They reveal the sharp teeth, three-fingered hand and pointed head of a typical theropod – a carnivore that walked on its hind legs.
The adult Yutyrannus would have been about 30 feet long, weighing 1.4 tons, with six inch long feathers. Although this is much smaller than its T.rex cousin, it was 40 times heavier than Beipiaosaurus, the previously plumed record-holder.
The feathers of Yutyrannus were only simple filaments, certainly not adequate for flight. This evidence supports the theory that the feathers evolved for insulation instead. The soil has been dated to around 125 million years ago to the mid-Cretaceous period, and it is thought this was a particularly chilly time. It is not known for certain whether Dinosaurs such as Yutyrannus were warm or cold blooded, but in either case even a thin insulating plumage could be selectively advantageous, aiding survival in more extreme climates.
Conversely, the feathers may have been used in mating displays, hinting at complex behaviours not traditionally associated with these terrifying lizards. Recent discoveries like this in China have bolstered the theory that birds today are the descendants of small feathered theropods that took to the trees, either for food or safety. Subsequently, it is thought, that pioneers such as Archaeopteryx then learned to glide or fly through the evolution of more advanced feathers.
Feathers are notoriously hard to preserve in the fossil record, so the true extent of feathered dinosaurs may never be known. But the sheer size of Yutyrannus is decisive, as we can now say with confidence that feathers were not solely evolved for flight. Instead, evolution hijacked existing features of sexual selection, or adaptations to the cold, and propelled dinosaurs into the skies.