India Hotspot for Emerging Diseases

From National Public Radio another eye opener on emerging diseases. A team of researchers from the Consortium for Conservation Medicine, the Institute of Zoology (London) , Columbia University and Univ. of Georgia have shown that infectious diseases such as SARS, Ebola, AIDS are on the rise and their emergence likelihood is spatially non-random. Some places are more likely to act as sources of these diseases than others. Being something of a spatial analysis buff and a map freak I found this most revealing:

Source: Nature

a) zoonotic pathogens from wildlife
b) zoonotic pathogens from non-wildlife
c) drug-resistant pathogens
d) vector-borne pathogens

Spin the combinations any way you like and India especially north India emerges as a hotspot for emerging diseases in every which way. Not very surprising considering the very high population density and proximity with domesticated animals. The recent outbreak of Avian Bird flu in West Bengal is a reminder that such threats are real and the assessed risks are not an outcome of some computer simulation done in a far away lab. In this case Indian authorities acted promptly to control the threat and even received a commendation from the UN Food and Agriculture Organization. Yet there are still worrying trends that we have be aware off. Take case d in above figure, the one that indicates risk distribution of vector-borne pathogens. Nearly all of India is a high risk area. It's not just population density that is the problem but the abysmal state of public sanitation and cleanliness in our cities and villages. The Surat plague epidemic some years ago shows that this is a clear and present danger we face. Case a which is risk from pathogens from wildlife also takes a more urgent meaning especially in the light of recent reports of deforestation and dwindling tiger populations. I have written about these issues in earlier posts from a perspective of biodiversity and wildlife protection, but human wildlife interaction is increasing in India due to encroachment into forest by people living at the margins of these forests and by continued logging of dense forests. This is what Kate Jones one of the paper authors had to say:

“Emerging disease hotspots are more common in areas rich in wildlife, so protecting these regions from development may have added value in preventing future disease emergence”

There is a positive spin to everything. The fact that this research identified India as a hotspot for pathogens from wildlife indicates we still have some wildlife areas left intact! Protecting them will be good for both animals and people.

Why Palaeontologists Love Mudslides

The Burgess shale was deposited as a series of mudslides. This was the conclusion reached after a detailed sedimentological analysis by researchers from Univ. of Leicester and the Royal Ontario Museum. The Burgess shale is one of the most famous and important fossil localities in the world. Science Daily and Live Science carried reports of this paper. Most estimates based on molecular phylogeny and fossils place the origin of multicellular animals (metazoans) in the late Proterozoic Vendian period ( at or just before 600 million years ago). The subsequent Vendian-Early Cambrian fossil record is sparse (more on that later). The Burgess shale which is Middle Cambrian, dated to about 515 million years is however unusually rich in fossils giving us lots of information about various aspects of Middle Cambrian metazoans.

What makes the Burgess shale so special? Normally during fossilization organisms with hard durable skeletons have a higher chance of being preserved. The soft tissues of these organisms decay upon death or are consumed by scavengers. And organisms which are entirely soft bodied may not be represented at all. So we are left with a biased record in favor of the morphological characters of ancient organisms that are more easily preserved. I mentioned that fossilization normally preserves only the most robust materials of the organism. But occasionally it can preserve very delicate structures as well. One way this has happened in the early Cambrian is through phosphatization of body tissue. The process is delicate enough to preserve animal embryos. However large body fossils have not been found preserved in this manner. The Burgess shale fauna represent another type of preservation mode. The mud slides that formed the deposit buried the Middle Cambrian community rapidly and deeply. The deep burial protected soft tissue from oxidative decay and also from scavengers. This has enabled soft tissue forms to be preserved as impressions upon the mud along with skeletal fragments. Fossil assemblages preserved under such unusual circumstances where even the soft parts of organisms are preserved are called lagerstatte.

Since the Vendian-Early Cambrian body fossil record is sparse, scientists have relied heavily on lagersttate like the Burgess shale and the slightly older Chengjiang fauna from China to understand Cambrian animal evolution. Such lagerstatte have so far not been discovered in Vendian and Early Cambrian strata. This has led to many misunderstandings regarding early animal evolution. Creationists who insist that biological complexity cannot evolve through intermediate stages have used the Burgess shale as evidence that animals arose "suddenly", ignoring the older fossil record. The media often uses terms as "sudden appearance", "in the blink of an eye" without properly explaining what these terms mean in a geological context. The term Cambrian explosion hardly helps. Explosion does not mean that at one time nothing existed and then Poof suddenly complex animals appeared on the Cambrian sea-floor. Explosion refers to the evolutionary radiation of metazoans that took place in the Early-Middle Cambrian over a time span of about 15-20 million years. The image below summarizes the Vendian-Middle Cambrian fossil record.


The Burgess Shale and the Chengjiang fauna have assumed such iconic status that reading media reports I sometimes get the impression that without these fossil locales we would know nothing about early animal evolution. But that is just not true. The early fossil record although sparse does show a gradual increase in grades of complexity in animals. This is seen through an increase in size and complexity of trace fossils as well as body fossils. Representatives of most skeletonized phyla can be recognized in the fossil record by Mid-Late Cambrian times. Taxa representing lineages ancestral to phyla (stem-groups) however have not been recognized in many cases. This means that the fossil record of the early Cambrian does not by and large preserve the detailed stages of body plan evolution. This may partly be because the initial evolutionary radiation took place in soft bodied forms before skeletonization evolved. Early skeletons may also have been quite fragile, disintegrating in small pieces upon death of the organism, making reconstruction of form difficult. And finally, evolution of novel morphologies may have taken place geologically rapidly in ecologically restricted less diverse lineages reducing their chances of being preserved in the fossil record. This situation will change as more fossils are discovered and improved systematics place problematic Early Cambrian taxa to their correct position within various animal clades. The Burgess Shale and the Chengjiang faunas represent a time when complex body plans of animals had already been assembled. So although they tell us a lot about the disparity (range of morphological forms) and diversity during the Middle Cambrian, they are less useful in terms of understanding body plan evolution and the early diversification of animals which most probably took place in the latest Vendian and Early Cambrian. A notable exception to this so far has been the work of Graham Budd on Arthropods. Using an analysis of ancestral and derived character states of Arthropod stem taxa from early Cambrian and Burgess type deposits, Budd has reconstructed the various stages through which Arthropods acquired morphological features characteristic of their clade. Arthropods have an exceptionally rich fossil record in the Middle-Late Cambrian. Such types of analysis are constrained by the paucity of stem group fossils for many other phyla. A few more preserved fossil rich mudslides from the early Cambrian will go a long way in filling that gap.

Can a Country be Entirely Carbon Neutral?

I heard an interesting talk on National Public Radio in their climate connections section. Costa Rica wants to be carbon neutral in the next decade or so. The country is already known for its pro environment stance having put stringent measures to protect its rain forests. Now it wants to go a step further and make further emission reductions to an extent that it has almost no net emissions. This is going to be quite a challenge. Costa Rican rain forests absorb about 2.5 million tons of CO2 per year, and Costa Rica emits from various activities about 12 million tons of CO2 per year. One way the report said that Costa Rica will decrease this gap is to pay landowners to plant more trees, funded largely by an increase on gasoline taxes. But experts think that the gap is too large and transportation emissions are increasing too rapidly for these schemes to work. According to the report Norway and New Zealand have similar plans.

Oddly the report missed out mentioning Iceland, which I feel has the best chance of coming close to carbon neutrality in the next couple of decades or so. Iceland is a small, culturally homogeneous country used to taking policy decisions by consensus building and referendums. This makes it easier for politicians to set long term goals. For example Iceland is the only country where the entire population has volunteered to put individual genetic information in the public domain for medical research. In this spirit Iceland has declared that it plans to make the transition to a hydrogen economy by 2030-2040. In terms of natural resources, they might just make it. Geologically Iceland is a mid oceanic ridge, one of the few places on earth where this ridge rises above sea level. Because of this, the entire country is underlain by a vast hydrothermal system, driven by magmatic heat. Iceland derives most of its electricity from this geothermal energy with a little contribution from hydro power, making power generation essentially greenhouse gases emission free. The trick now is to reduce emissions from transportation and here Iceland is aiming to run its entire transportation network, from public transport to its fishing fleets to personal vehicles on hydrogen fuel cells. Hydrogen cells are not something unique to Iceland but the manufacture of hydrogen mostly from electrolysis of water consumes a lot of electricity and if this is derived, as it mostly is in other countries from burning coal, then you are simply pushing your emissions to the power plant. Since power generation in Iceland is mostly from clean energy, the entire cycle of fuel production for transport promises to be clean.

All this remains a pipe dream for most other countries. Power generation for example in China and India is mostly coal driven and this situation is unlikely to change in the near to medium future of about 20-30 years, the critical time bracket in which most climate change experts says we must reduce emissions to avoid "irreversible changes" to the climate. Methods of sequestering CO2 by pumping it in underground storage are available but are only locally employable due to geological constraints and are very expensive. Other forms of alternative technologies like wind and solar suffer from a combination of local and temporally sporadic availability and high costs compared to fossil fuels. Nuclear energy seems to be constrained by costs and public suspicions on its safety. Transportation fares no better. The much inflated balloon of biofuels was punctured some time back by research which indicated that again in the short to medium term increasing demand for biofuels will adversely impact land use patterns causing deforestation and destruction of wetlands. The gains in emission reductions at the wheel will be more than offset by the increased emissions during the production of biofuels.

Where does all this leave us? Research budgets for alternative energy seem to be falling and there is no indication that countries like China and India are moving towards cleaner energy, both having plans for massive increases in coal fired power plants. The recent mad rush to claim sovereignty over portions of the Arctic sea-bed for future oil prospects indicates that no developed country is in a position to wean its economies from fossil fuels for some time. The transition from fossil fuels to cleaner renewable energy is likely to be a very gradual process. In the meantime I think it will be time well spent if we shift some of our focus from preventing global warming to adapting to it.

Arctic Oil: U.S. Gets With the Programme

New maps of the Alaska arctic continental slope show that the slope extends about 185 km further from the coast than previously thought. This makes a huge difference to how much territory the U.S can now claim for oil rights. In a previous post I had written about the geo-political situation around the Arctic ocean. Russia, EU, Denmark, Canada and the U.S are all slugging it out to carve the biggest barrels out of the arctic sea-bed oil. The law of the sea give countries exclusive mineral rights up to a distance of 200 nautical miles from their coasts. The U.S is yet to ratify this treaty and the recent discovery may provide Congress with the push needed to do so. A lot of oil is though to lie beyond this exclusive zone, and with the Arctic ocean becoming ice-free in the summers, countries are now scrambling to show that geologically their continents extend beyond this zone. This would according to an exception in the law of the sea treaty give them additional rights. Russia says geology proves that the Lomonosov ridge is part of their slope, but I think Denmark can make an equally convincing claim. The geological situation is seen in the image below.

Credit: NOAA

The current U.S claim is almost certainly going to be challenged by the Canadians. Below is an image of the U.S claim, polygonal area marks out the extension of the Alaskan continental slope.

Credit: UNH/NOAA

Estimates vary about the total arctic reserves but the more optimistic one's place about 25% of the world's undiscovered oil and natural gas in the these frigid depths. The director of NOAA's Office of Coast Survey had this to say about the new maps:

"These are entirely new insights into what the ocean bottom looks like. The data will be used to gain a better understanding of many things, including ecosystems and climate circulation models."

Hmmm.... somehow I think oil and not ecosystems will be given priority!

So, here's how this is going to work. Global warming is clearing up Arctic ice, giving access for more exploration and development of oil and natural gas deposits, which in turn will add to further global warming.

What a great scenario!

India's Tigers and Forests

I have been blogging quite a bit about the state of India's wildlife and forests. There has been a lot of news about this topics lately. Not all of it bad. Recently the Indus dolphin was sighted in Punjab river Beas after the gap of about 70 years. But overall the news has been depressing. Bharatpur bird sanctuary has virtually dried up. According to the latest census the tiger numbers in the country are now thought to around 1400 only, much below the earlier figure of about 3000 given by the government. And there is more bad news of the state of the forests. The latest census of the Forest Survey of India reveals that between 2003 and 2005 India lost about 700 sq km of prime forest land and suffered lots of degradation of dense to moderately dense forests. By a coincidence I had posted on this topic a few days before this report (2003-2005) came out. That post used data from an earlier census (2001-2003). That census showed that forest cover has actually increased by around 2700 sq km. But the devil is in the details. All that "growth" is either an artifact of better mapping due to improved satellite resolution or counts monocultures planted on degraded land away from any critical wildlife habitats. The core forests in and around tiger reserves for example continue to vanish and become degraded. Afforestation is not being directed to where it is most needed. I had used the Nameri tiger reserve in Assam to illustrate this point using images more recent that those used in the 2003 survey. Now this latest report confirms that prime forest areas are shrinking.

All over the world, not just India the basic problem has been that population pressures have altered the landscape in often irreversible ways. Contiguous forested areas have become fragmented. They are now islands surrounded by human presence and activities. In India nowhere is this illustrated with more clarity and devastating realization than where the Himalayan foothills grade into the north Indian plains. Below image shows this situation where the ranges suddenly give way (green dotted line) to irregular jagged pieces of forest, isolated from other such pieces, islands surrounded by intense agriculture land use.

The brown dotted polygons mark the approximate boundaries of the Dudwa tiger reserve in Uttar Pradesh. Three patches of forest which are becoming increasingly fragmented and frayed at the edges literally. How do you manage healthy tiger populations is these isolated islands? They are few 100's of sq km large, able to sustain a few ten's of tigers at most in each of the forest patches. How do you ensure a healthy gene pool with such small numbers? Some years ago when I was living in Florida, wildlife authorities were faced with a similar problem with the Florida panther. A small population showing signs of debilitating health effects from inbreeding. So, the Texas cougar a close relative of the panther was introduced in the Florida habitats of the panther. The results are encouraging. Florida panther populations today are healthier. Increasingly it is not going to be enough to just manage the physical aspects of the ecosystem. Our wildlife management plans currently claim to focus on afforestation, resolving human animal conflicts at forest margins, controlling logging and poaching. These are worthy goals. Poaching especially is suspected to have disproportionately contributed to the recent decline in tiger numbers. But even if our reserves become well protected against poaching we have to live with the reality that most of our tiger habitats are never going to connected to each other again and animals trapped in isolated habitats will need more help. We will have to manage their biology for them as well. Conservationists often talk about setting up migration corridors but take a look at the above image of Dudwa which for administrative purposes is one tiger reserve. The three forest patches are separated by 10's of km of intense agriculture land use. It is inconceivable that we can change land use and relocate humans on this scale. Most reserves in India are now separated by 100's of km of no forest areas and migration corridors cannot be thought of as a general solution to habitat isolation. In this context saying India has a total of 1400 tigers or 3000 tigers or some other number becomes less meaningful than assessing what viable population can be maintained in each of the forest islands across which natural migration and gene flow is now impossible. By such separate assessments may come the unpleasant knowledge that 1500 to 2000 is the total healthy population that can be sustained given the limited amounts of forests left. Off course this number will be hopefully much more, but to come to a stage where we are in a position to develop a tiger management plan backed by some hard science we will need increasingly focussed biological information on individual tiger populations. This means developing genetic databases of tigers to understand the genetic structure of populations. Regular screening for signs of inbreeding and setting up a well funded programme for induced gene flows across our tiger reserves. Are we geared up for a biological management plan for tigers?

What has been the reaction of the government to the recent report that 700 sq km of prime forest has been lost?

"Overall, the decrease is insignificant. It is not worrying as India's forest cover has more or less stabilised and ranks number 10 globally on a per capita basis," said Devendra Pandey, director-general of Forest Survey of India.

It is a statement only an Indian bureaucrat can make. Factually correct in a very narrow sense but showing a contemptuous arrogant indifference to the ground ramifications of the finding. Pretending everything is fine because we rank number 10 globally on a per capita basis. How on earth is that hollow boast supposed to help the tiger? Dismissing the real loss of prime habitat by pointing out that our forest cover has more or less stabilized. In an earlier post I pointed out how meaningless this stabilizing is in the context of the health of critical wildlife habitats. Afforestation is simply an exercise carried out to balance the books of the ministry of environment and forest. Let's take another look at how this "stabilization of forest cover" is working out. Below is a forest cover map of Buxa tiger reserve in West Bengal. This data was complied from 2001 satellite images.

Source: Forest Survey of India

Green is dense to moderately dense forest and yellow is open forest which has about 10-40% forest cover. Look at the area around the red arrow. And compare it with a close up below of the same area taken in 2006.


If our afforestation programme really was meaningfully designed, this open forest shown in 2002 should have been targeted for improvement. The reality? By 2006 the entire area has been converted to farmland. "Ground Truthing" in remote sensing parlance refers to the validation of automated classification algorithms used in land cover mapping. Over here the term ground truth has taken on a much more urgent meaning. The truth is that our prime ecologically rich forest areas are disappearing but the government doesn't seem to care. Through its reports it is misleading it's citizens by creating statistical illusions of forest cover "balance" and "stabilization". As long as somewhere far away an equivalent amount of area is greened with monoculture plantations the forest department goals of "stabilizing" forest cover will be met and a false victory proclaimed.

Write to your state forest department and demand action. The link to the Maharashtra forest department is : Maharashtra Forest Officials

See also:

India Gains Forest Cover, But....
Bharatpur Bird Sanctuary Dries Up
Indus Dolphin Sighted in Punjab