Transport Options for Indian Cities

The city of Muenster, Germany has this message for urban transport planners in India:


I got this from Tim Harford's blog who got it here. Despite the quibbling over camera zoom and angle and whether the picture depicts transport patterns realistically, I think the poster makes a great point. The city compares the space used by various modes of transport in moving a comparable number of people. Here are the stats for moving 72 people

Bicycle: 72 people are transported on 72 bikes, which requires 90 square meters.

Car: Based on an average occupancy of 1.2 people per car, 60 cars are needed to transport 72 people, which takes 1,000 square meters.

Bus: 72 people can be transported on 1 bus, which only requires 30 square meters of space.

Besides space occupied there is also the problem of pollution. Bicycles don't emit pollutants and buses pollute less per passenger km traveled than other motorized transport. Yet currently we tax private vehicles less than public transport buses creating distorted incentives for vehicle choice. The various taxes that favor private vehicles more than bus public transport are nicely summarized in this letter from the Centre for Science and Environment to finance minister P. Chidambaram.

Coral Ecosystems of India's West Coast

I came across a small news report in this Sunday's Times of India of the recent discovery of a thriving coral ecosystem about 80 nautical miles from Panjim in Goa. This coral reef system has developed atop a shallow 40 km long bank known as Angria Bank. The sea floor surrounding this bank is about few 100 feet or so deep and suddenly rises to just 20 meters or so. The image below shows the location of Angria Bank.


The bathymetric surface is also seen in the image and although generalized you can still see the topography of the sea-floor on a regional scale. The dotted line marks the edge of the continental shelf of India. The shelf is the drowned extension of the continental crust of India. When you say that plate tectonic movements caused India to split away from Africa, the split did not occur at the position of the present coastline but roughly at the edge of the continental shelf. Back during the Pleistocene glaciation much of this shelf may have been exposed as sea-levels periodically dropped by a few hundred feet worldwide. As the glaciation ended around 12,000 years ago, sea-levels rose up to the present coastline, drowning large parts of the shelf. The Angria Bank as you can see is at the edge of the shelf. At the point marked Angria Bank you can see couple of elongated humps on the sea floor. That is the raised shallow bank. To the west the sea floor suddenly becomes deeper along a steep slope that grades into the deep sea plains. This marks the transition from the continental crust of the shelf to the ocean crust of the deep sea plains. The banks topographic high above the surrounding sea bed is probably structural in nature. The west coast shelf of India is riddled with coast parallel faults which originated with the tectonic breakup of India first with Africa and then with Madagascar. Vertical movements along these faults produce horst and graben structures, elongate ridges and depressions. The Angria Bank is likely such a horst. The coral community there must have started developing after the Holocene sea-level rise few thousand years ago and coral growth continues today. I am not sure what the composition of the foundation of this reef is. It could be basalt rock, the submerged continuation of the continental flood basalts that are exposed all over Maharashtra or it could be older Cenozoic sediment or even Pleistocene reefs developed during the interglacial phases of the Pleistocene glaciation when sea-level was high.

Such isolated shallows as ideal environments for coral growth. Far from continental rivers, the water are clear and devoid of terrigenous sediment which can make water turbid. Such turbidity can prevent sunshine from penetrating the water, inhibiting the symbiotic algae that lives within corals from efficient photosynthesis. Too much suspended sediment may also clog up the coral animals feeding mechanism. Many of the world's major coral ecosystems such as the Bahamas, Bermuda, Lakshadweep, Maldives are situated in such isolated shallows, some distance away from major continental river mouths and deltas.

The newspaper reports that the Maharashtra tourism department hopes to make this into a hot eco-tourism spot. I searched for Angria Bank and found several private tourist operators already offering a "four hour ride on speed boat" from Panjim for world class diving to the Angria Bank. Exploring coral ecosystems is one of the great experiences. My graduate adviser and I used to teach a class in carbonate depositional systems and took students to study the Florida Keys. I can tell you no matter how many nature documentaries you have seen, nothing prepares you for your first encounter with coral reefs. That world on the sea floor is something else. Besides just catering to tourists this newly found ecosystems needs to be studied in detail. Reef Watch a Mumbai based organization has already started a research program to document and study the biodiversity. And I hope the government steps in and works towards making the Angria Bank a marine bio-reserve. Better tourists with a camera than fishing trawlers.

Ancient Impressions of Sex

Fossils can tell us a lot of things about ancient life than just what the organisms looked like. Animals are preserved in a variety of ways in the fossil record. The most common mode is for the hard parts or skeletons of animals to be preserved. Skeletons tell us about the external form of the animal but skeletal associations inform us about paleoecology and paleoenvironments. Soft body parts usually decay away quickly but under certain conditions can leave behind impressions upon a soft substrate or are even mineralized as exemplified by phosphatized animal embryos from the late Proterozoic of China. Such rare preservation may tell us about developmental aspects of ancient animals. Another mode of preservations are trace fossils which as the name suggests as traces left on the substrate by activities of animals. These can be tracks and trails recording the locomotion of animals, groove or scratch marks of animals with appendages or tubular structures which usually indicate burrowing by animals into the sediment. These give us behavioral cues about animals. Animals who are immobile can sometimes be preserved in their living positions. That can tell us a lot about life history and ecologic strategies employed by these organisms. Some recent research has found just such fossils from south Australia in their living positions and it makes an interesting story.

Evidence from molecular phylogeny and the fossil record suggests that multicellular animals (metazoans) evolved around 600 million years ago in the late Proterozoic from a colonial protist ancestor. The Choanoflagellates are taken to be the nearest living equivalent of the ancestral protist. By mid Cambrian (about 520-515 million years ago) animals had evolved complex body plans recognizable in living phyla. There is an interesting temporal control on the mode of preservation of animals during this period which is taken as a reflection of how environments were modified by the evolution of successive grades of biological complexity. One of the earliest record of metazoan body fossils is the Ediacaran biota (570 to 540 million years ago), which are mostly impressions of animals preserved as body casts. In the late Proterozoic bacterial mats covered the shallow sea floor extensively. Animals often left impressions upon these soft mats or on soft mud. The mats trapped fine sediment which filled these impressions. Bacteria also produced a bio-geochemical environment which was conducive for precipitating of calcium carbonate which lithified the fine sediment thus preserving the filled impressions as a cast. Later in the early Cambrian when the first grazers evolved, bacterial mats growing on the sea floor were eaten up. As animals evolved locomotion bioturbation would also have destroyed any delicate body impressions by stirring up sediments. This type of preservational environment disappeared from the shallow marine shelf areas. Tracks, trails and burrows became more common as the sediment interface became increasingly disrupted by animal locomotory and feeding activities. The presence of grazers led to the evolution of predation. Predator- prey evolutionary arms races led to the origin of body armor for protection in the prey and breaking past the protective armor in the predators. Hard body skeletons appear in the fossil record by early-mid Cambrian.

Back to the main theme. Science daily reports on the discovery from the Ediacaran biota of Australia of the earliest instance of preservation of sexual reproductive strategies in animals. The star fossil caught in the act is Funisia dorothea a tubular organism preserved as lithified impressions.


Droser lab, UC Riverside

Judging by the image above the fossils appears to be a lithified cast. The tubular ropy structures have a slight relief against the enclosing material suggesting a slightly higher resistance to weathering. Funisia tubes were rooted to the sea-floor much like corals and sponges. The interesting thing about the fossils is the closely packed tubes which have been interpreted as a pattern of sexual propagation that accompanies animal sexual reproduction. Living in such densely packed communities increases the chances that sperm and eggs released in the water have the best chance of meeting. Living organisms like sponges and coral often reproduce sexually producing huge numbers of offspring. The researchers believe that the dense packing of similar sized fossils is highly suggestive of a similar larval "spatfall" i.e. large number of larvae being born at one time. I wrote above that this may be the first preserved evidence of sexual propagation in animals. This is not the same as saying that this is the first or earliest instance of sex in animals. One of the authors says "In Funisia, we are very likely seeing sexual reproduction in Earth's early ecosystem -- possibly the very first instance of sexual reproduction in animals on our planet." This is highly misleading. Sex is very ancient process, preceding the evolution of animals by hundreds of millions of years. Bacteria too have a form of sex, so do plants and fungi. Single celled Eucaryotes had evolved forms of sexual reproduction much before the advent of multicellular animals like Funisia.

Ediacaran biota are morphologically diverse. Some forms are thought to represent extinct clades which left no descendants. The taxonomic affinity of the fossil Funisia dorothea is not known and may represent one such extinct group. Some fossils have been shown to represent possible stem ancestors of Cambrian clades. These include Cnidarian and possible Arthropod stem forms. Such morphologic diversity implies diverse life strategies. These appear to have evolved very early in the history of animal evolution. I am not sure I agree with the general tone of the report which suggests that this will cause something of a rethink on animal evolution. When evolutionary radiations take place in empty ecologic zones, as late Proterozoic shallow shelf areas undoubtedly were, evolutionary novelty appears relatively quickly in response to major adaptive opportunities. This pattern of early evolution of novelty is seen not just during the Ediacaran radiation but throughout the history of life whenever empty adaptive zones have been filled for example during the early-middle Cambrian and later after the Permian and Cretaceous mass extinctions. That animals show sexual reproductive strategies early in animal evolution should not come as such a huge surprise.

PZ Myers gets Expelled

PZ Myers who blogs at Pharyngula has an absolutely hilarious post on how he got expelled from a movie theater in Minneapolis. He along with a guest had gone to see the creationist propaganda movie Expelled. As he stood in line a policeman came up to him and told him that he was on a blacklist and had to leave immediately which Myers did. PZ Myers who teaches biology at University of Minnesota has been a nemesis of the creationist community, but what a silly infantile reaction to ban him from the movie! What is even funnier is that they allowed his guest to go in...

Small Humans and Science Outreach

One good place to follow science research is Science Friday on National Public Radio. Last week they had a interesting talk on newly discovered fossils of humans from the island of Palau. The unusual aspect of these fossils is that they most probably represent the remains of an extinct population of pygmy humans that inhabited that island about 2000-3000 years ago. Small body size is a common feature of hunter gatherer populations living in tropical habitats and these fossils show a body size comparable or slightly smaller than pygmy populations of S.E.Asia and Africa. The scientist in conversation Lee Berger gave quite a few insights into the phenomenon of island dwarfism which is an extreme reduction in body size as a response to living on resource poor islands where life spans are short and early reproductive maturity evolves at the expense of continued body size growth. I thought this topic would be of interest to Indians, since we have our own pygmy island populations in the Andaman islands. Recent genetic analysis suggests that these original inhabitants of the Andaman represent a population of great antiquity perhaps descendants of people who migrated out of Africa in the Late Pleistocene around 50,000 years ago and settled in the Andaman islands shortly thereafter. Their short stature is thought to have evolved independently of the African pygmies. The thought that a pygmy population living in another place went extinct is sobering given the current situation of the various Andamanese tribes such as the Onge. These people now number in their few hundreds and live in special reserve areas mostly out of contact from other island inhabitants. Anthropologists believe that such small statured human populations were once common all along the S.E. Asian islands from the Andaman to Malaysia to Philippines to Indonesia. Immigration of agriculturists in the past couple of thousand years have marginalized them. Only a few pygmy tribes remain today along these island chains. The Palau population may have been such an island outpost of small people.

Shifting tracks what struck me about this talk was how entertaining it was. Even someone with no special interest in anthropology will find that "the excitement of doing science" really comes through the enthusiastic give and take between host Ira Flatow and the guest Lee Berger. I feel this kind of a conversation about science is missing between Indian scientists and the public. Our scientists are by and large invisible. During school we used to meet them on that boring tiresome "science day" where hordes of kids are paraded through labs and given pep talks by all too grave looking scientists. Elsewhere they get invited occasionally on TV and in the print media, but the topics discussed are always too grandiloquent, India's moon mission, launch of a new satellite, general discussions on global warming. In newspapers too there is a lack of regular science columns where specific research topics or a specific piece of work carried out by Indian scientists in Indian labs is written about. Online editions now offer an opportunity to invite scientists or science journalists to start blogs but so far our media have not used this avenue. I am really not sure how much to blame the media for this. Science does not seem to attract most young Indians as an exciting career option and the lack of engagement of scientists by the media is probably a reflection of this. There may also be a perception that unless you are doing some earth shattering piece of research its not worth reporting on. But that is really not the point of a science conversation. The point is to engage the public and instill in them an interest in the practice of doing science. All discoveries big and small are interesting to the working scientist and programs such as Science Friday convey that excitement to listeners with great effectiveness. Besides mainstream media today there are avenues for Indian scientists to create their own audience primarily through their own blogs. This opportunity for science outreach still remains woefully unexploited by Indian scientists. I don't have a count of how may science faculty and science researchers blog but I suspect hardly any do. In Pune for example, there are several institutes of higher education and research, University of Pune, IUCAA, Indian Institute of Tropical Meteorology, National Chemical Laboratory but I have yet to discover a blog by a faculty or researcher from any of these places. What are other ways for Indian scientists to have a conversation about science with the public? An initial step may be University radio stations. These are essentially low power community radio stations. Mumbai and Delhi University have already started broadcasting and hopefully science will get some space. Individually their reach will remain local. But can a network of such University stations be set up with program sharing? Another way to get around the local coverage would be to set up attractive websites and provide online radio streaming and podcasts of programming. In general community radio may prove to be a really good tool for science outreach and our science institutions need to capitalize on the recent FM boom and be more proactive in using airwaves to promote science conversations with the public.