Unique red-headed monitor lizard found

At over a metre long and with a bright red head, you might think the Torch monitor lizard would be quite distinctive. In fact, nobody knew such a lizard existed, until a group of American and Finnish scientists stumbled upon it last year. Their discovery has only just been reported in the journal Zootaxa.

The Torch monitor - hide and seek champion. Image: Valter Weijola

The Torch monitor, or Varanus obor, is named for its most distinctive feature, its bright red or orange face. In fact, it is the only monitor lizard known to have evolved distinctive red pigmentation.  It lives mainly in coastal palm swamps and, like many monitor lizards, feeds on small animals and carrion.

The lizard is only found on the island of Sanana. Sanana is part of the Moluccan archipelago, nestled to the west of New Guinea in Indonesia, where the lack of predatory mammals has allowed large lizards like the Torch monitor and the closely-related Komodo dragon to reach the top of the food chain. But why haven’t mammals colonised the islands and supplanted the reptilian predators?

It’s all down to sea level: animals colonised the many small islands in the area during periods of low sea level such as ice ages, when sea levels were more than 120 metres lower than today as the water was locked up in polar ice caps. However, the entire region is sliced in half by a deep sea trench running from the Indian to Pacific Ocean, which never dried up. It prevented mammals from the Asian mainland from reaching the southern and eastern islands and Australia, and allowed monitor lizards to diversify and dominate terrestrial ecosystems.

Known as the ‘Wallace Line’ the sudden change in animal species was first described by Alfred Russell Wallace, who most famously worked out the details of evolution at the same time as Charles Darwin made his discoveries.

Paper Reference: Weijola, V., and Sweet, S. (2010). A new melanistic species of monitor lizard (Reptilia: Squamata: Varanidae) from Sanana Island, Indonesia. Zootaxa. 2434, pp 17–32.

Complex government spurred growth of ancient nations

Red tape, bureaucracy, and the nanny state have all been blamed for stifling progress and holding us back, yet it turns out a bureaucratic administration is just the thing if a nation is looking to expand.

The heart of a modern bureaucracy - inside, it's piled high with red tape. Image: Jedyooo/Wikimedia

The research, carried out by an American researcher, compared the archaeological remains in the Oaxaca Valley of Mesoamerica with the remains of five other ancient nations in Peru, Egypt, Mesopotamia, the Indus Valley, and China.

These are known as primary states – ones that formed without encountering other nations – and they are ideal places to study the original creation of nation states without worrying about outside influences.

The six primary states all show a distinctive pattern of growth, where expansion of each nation’s territory happened at the same time as the development of the bureaucratic government offices required to govern the growing nation. The researcher thinks this is no coincidence: only a bureaucratic administration and could support expansion, and only expansion could provide the resources needed for a fledgling state to support a bureaucracy.

Taking this one step further, the research suggests that even modern bureaucratic governments may be based on this need to expand, and we need to watch international politics very carefully if we are too keep this ‘predatory’ urge in check.

Bureaucracy is rarely seen as a good thing, adding layers of complexity and time to even the simplest of tasks, yet it seems to be an essential part of the growth of any nation. Academics have always recognised the necessity of bureaucracy in forming nations, but previous work suggested the bureaucratic processes were created before nations expanded. The new study seems to contradict that idea.

Of course, this raises a question for this blogger of whether the creation and growth of bureaucratic government can go too far, and what happens when it does? Answers to be submitted in triplicate on form XS42b by the third Tuesday of next month!

Paper Reference: Spencer, C (2010). Inaugural Article: Territorial expansion and primary state formation. Proceedings of the National Academy of Sciences. 107(16), pages 7119-7126. DOI: 10.1073/pnas.1002470107

An ash-filled sky

Image: NASA/MODIS Rapid Response Team

The plume of volcanic ash that is responsible for grounding planes across northern Europe traces a dirty smear across the Norwegian Sea in this photo snapped by NASA’s TERRA satellite.

A volcano beneath the Eyjafjallajoekull glacier on the south coast of Iceland is blasting ash up to 11 kilometres into the atmosphere. At this altitude, strong winds are blowing the plume of ash south-eastwards, towards the UK and mainland Europe.

But why is volcanic ash such a problem for aircraft? The ash contains tiny particles of volcanic glass, which can be sucked into jet engines. Jet engines operate at temperatures high enough to melt the glass particles, which causes sheets of glass to form, blocking fuel nozzles and other sensitive components.

The tiny glass shards are also abrasive, and they’ll quickly damage cockpit windows – reducing visibility. The risk to aircraft from volcanic ash is so great that it is far safer to cancel all flights until the ash plume disperses. As the volcano is still erupting, this may take some time!

The volcano near Eyjafjallajoekull first erupted on the 20th March 2010, following months of small earthquakes, and caused Icelandic authorities to evacuate around500 people. The second eruption on the 14th April was ten to twenty times larger than the first because this time the magma came into contact with glacial ice, causing a powerful explosion, which threw ash high into the atmosphere.

While a potential hazard for aircraft, the ash probably isn’t a major health hazard for the UK population. The ash plume is so high that ash particles aren’t expected to reach the ground in the UK, according to a statement from the Health Protection Agency. So the only thing you need to look out for are the predicted beautiful red sunsets!

Animals thrive without oxygen

We can’t survive for very long without oxygen. Researchers thought the same was true for every other animal, until an Italian and Danish team found tiny animals thriving in oxygen-free sediments deep below the Mediterranean Sea.

A Loricifera called Spinoloricus: tougher than it looks! Image: Danovaro et al (2010)/BMC Biology

The tiny animals are known as Loricifera, and they grow to just one millimetre long. They were found living in anoxic (or oxygen-free) sediment on the Mediterranean seafloor, in conditions that would kill other animals fairly quickly.

Anoxic basins in the Mediterranean seabed are some of the most extreme environments on Earth. Over 3000 metres below the waves, a thick layer of salty brine collects in shallow basins, preventing oxygen dissolved in the seawater from reaching the sediment. The sediment is also packed with poisonous hydrogen sulphides, and the water at that depth is under extreme pressure, meaning the Loriciferans need a whole host of specialist adaptations just to survive. They rely on a trick used by many extreme-living single-celled organisms to generate energy without using oxygen, but this is the first time anyone has seen a multi-cellular animal do so.

But how do researchers know that the Loriciferans were spending their entire lives in the anoxic basins? The tiny beasts may have just drifted in from another patch of seabed, died, and then been scooped up in the sediment samples. To make sure this wasn’t the case the researchers used a fluorescent dye that only stains living cells, showing many of the Loriciferans were still alive. They also showed that there was no way the creatures could just have drifted into the basin in which they were found.

Researchers have known for a long time that bacteria, viruses and other single-celled organisms can survive in such hostile conditions, but this is the first evidence that multi-cellular animals can live, and reproduce – the researchers found several Loriciferans carrying eggs – quite happily in this bizarre alien world.

Paper reference: Danovaro, R., Dell’Anno, A., Pusceddu, A., Gambi, C., Heiner, I. and Kristensen, R.M. (2010) The first metazoa living in permanently anoxic conditions. BMC Biology, 8:30 doi:10.1186/1741-7007-8-30

Acidic oceans threaten marine life

Our oceans are more acidic than they have been for forty million years, according to a group of scientists from Spain and Australia. Acidic conditions, caused by increased levels of CO₂ dissolving from the atmosphere into the oceans, are damaging the fragile ecosystems on which many people rely for food.

A fossil foraminifera shell. Image: Hannes Grobe/Wikimedia

The scientists reviewed the latest evidence for ocean acidification. They found that there is strong evidence that the chemistry of our oceans is changing as atmospheric CO2 levels increase, and that these changes are happening around 100 times faster than they have in the past.

Marine animals, including molluscs and crustaceans, with shells made from calcium carbonate are at risk from increased acidity. The more acidic water means there are fewer carbonate ions available, so the animals build much thinner shells, leaving them vulnerable to predators.

Corals, which support a huge number of marine species, also rely on the same process to build their tough skeletons – less carbonate in the water means they can’t grow as quickly. Coral reefs are constantly being eroded by the power of the sea; the tiny animals that build coral reefs only just managing to create new coral faster than they are destroyed. Increased acidity pushes this delicate in the other direction – coral reefs will be destroyed faster than they can grow.

Surprisingly, the change in ocean pH required to cause such dramatic effects is tiny. A decrease of 0.1 pH units (acids have a low pH) since the industrial revolution has already caused some marine animals, known as foraminifera, to produce thinner shells. The scientists predict ocean acidification could cause a 0.4 drop in pH by 2100, with potentially dire consequences.

Our best predictions, based on our understanding of ocean acidity levels far into the past and the effects we can see happening around us today, suggest acidification could cause serious changes in our oceans over the next few decades. This latest review of the research paints a rather bleak picture, unless we can do something to clean up our atmosphere.

Paper reference: Pelejero, C., Calvo, E., and Hoegh-Guldberg, O. (2010). Palaeo-perspectives on ocean acidification. Trends in Ecology and Evolution. Available online: 30 March 2010. DOI: 10.1016/j.tree.2010.02.002