The dodo birdhe tiny, tropical island of the Republic of Mauritius is located near South Africa, east of Madagascar. Its seven hundred square miles are home to just over one million Mauritians, who are largely Hindu and Roman Catholic. Although the official language is English, less than 1 percent of Mauritians speak it. Instead many Mauritians speak Creole and Bhojpuri a language largely spoken in India. The island is also the former home of the dodo bird, which has been extinct for more than 300 years a bird that is responsible for putting the otherwise unknown nation on the global map. Mauritius is the only known home of the chubby bird, which has since become a point of national pride and has generated tourism for the country. The tourism interest in the dodo being that it is one of the best documented extinct animals that existed, and its death is a direct result of its interaction with humans. There is Dodo Travel & Tours and The Dodo Museum, dodo snow globes, and the idea for a frothy dodo cocktail has been floated around, according to a 2007 report from The New Yorker. The animal even appears on the Mauritian coat of arms and a statue of the bird is at the SSR International Airport. Zoologists and paleontologists from around the world visit the country to try and uncover the life of these little-understood creatures. The culture of Mauritius is a combination of Hindu, Muslim, French, Chinese, and African and the food, dances, and holidays observed are a reflection of that diverse blend. Among the holidays celebrated in Mauritius are the birthday of Hindu god Ganesha, the Chinese Spring Festival, the end of Ramadan, fire-walking ceremonies, and Tamil celebrations, as well as the Hindi festival of Holi where women and men joyfully squirt each other with brightly colored waters and powders.The dodo is one thing that that seems universal on the island nation, the extinction of the bird leaving an impression of resentment and a hatred of colonialism with islanders. Mauritius has a history of imperialism. It was first settled and abandoned by the Dutch, afterward it was settled by the French, and then conquered by the British in 1810.This anti-colonial sentiment recently came out during the 2006 Dodo Expedition, when paleontologists and zoologists predominantly from England and the Netherlands began a dig on land rich with dodo bird bones.In the 2007 New Yorker article, Digging for Dodos: Hunting an Extinct Bird, Ian Parker reported on the dig and some of the resistance scientists faced when working on uncovering the extinct birds, with local media and citizens criticizing the English and Dutch as greedy, exploiting the dodo for the second time by unearthing its bones. The English-language News on Sunday ran an editorial cartoon showing two goofy, salivating, wide-eyed Caucasians chasing a dodo skeleton, Parker writes in Digging for Dodos. The dodo was saying Youve eaten all my flesh, cant you allow my bones to rest in peace? During the dig, it would seem that islanders made little effort to conceal their feelings about foreigners disrupting the land. Team members rarely left the estate without someone saying, Where are you from? Holland? Oh, you ate the dodos. The recent dodo pride wasnt just a new-found interest in island history and culture from Mauritians, though. This passion for the dodo coincided with the European Unions ending the practice of buying sugar from former colonies at hearty prices. At that time, the landowners of areas rich with dodo bird bones began marketing their historical treasures, Parker writes. Sugar goes down, dodo goes up, says one scientist on the Dodo Expedition.

Its widely believed that the bird immigrated to the island by flight. A relative of the pigeon and dove, the dodo found no natural predators on the island and had an abundance of food, eventually evolving into a rounder version of itself with useless wings, nesting on the ground and over time growing one meter tall and weighing in at 23 kilograms.Tales from a Tanzanian AdventureFriday, 8:30 AM. Anxiously awaiting the arrival of our already half-an-hour late vehicle, we begin to wonder if we have crossed the threshold of African Standard Time. Urged to call our agent, Amit reluctantly agrees to drop 300 of his remaining 600 shillings in order to call and find out the ETA of our driver, Vincent, and cook, Bosco. Minutes later, the souped-up excursion-sized Landcruiser arrives massive tires, three rows of paired captain seats, a built-in fully powered mini-fridge, electrical outlets that dont work, and best of all, the type of sun-roof that would make a convertible jealous. Stocked with M&Ms, our saving grace, were off!Crossing the gates into the western Serengeti, the landscape quickly changes from rows of Coca-Cola and Sprite faced buildings to endless straw shaded fields. We are all excited by our first sightings of zebras, wildebeest, and gazelles, but soon grow anxious to see the rarer animals. Priyankas wish list: 1. baby elephant, 2. male lion, 3. lots of giraffes. The landscapes are incredible. Herds of wildebeest are everywhere, as the timing of our safari happens to coincide with their annual migration through the western Serengeti. Interestingly, just like humans trying to escape the heat, they often cluster in groups in the shade of some of the bigger trees that happen to spring from the occasional lush spot in the otherwise dry, flat plains. Midday, they group directly under the trees, but as the sun looks sideways in the late afternoon, the groups slowly seep out from under the branches in pursuit of the slowly elongating shadows.

Only three hours past the western gate, we happen across a water source, and with it, a gathering of animals. In dry season, the dwindling number of rivers and streams funnel the herds in the perfect bait for hungry lions. For us, just seeing the lions is a gift, but Vincent believes they may be preparing for an attack, so the engine is turned off and we become part of the scene. A female lion and her cub arise from their slumber; with ears pointed and shoulders tense, the lions head lowers. What a contrast the calm and confident lion was from the six of us, as we looked all around trying to grasp a sense of what was going on. We click away with our cameras, knowing something is amiss. Suddenly, she shoots out from under the tree, through the brush and around towards the back of the car! Within seconds her jaws are clenched around the neck of a wildebeest, and she is joined by the regal male lion. It happened so quickly that all of us had failed to even notice. The sight is astounding. Just ten yards away from our vehicle stand the male, female, and cub with a dead wildebeest.

We were more than spoiled on our first day of the safari, but nonetheless continued to be awed by the beauty of the landscapes throughout the rest of the weekend. The grandeur of fifty plus elephants controlling their stomping ground and families of giraffes careening their necks to enjoy their balcony view over all the action were only a couple of the memorable sights. And of course the lion spottings, which were interspersed throughout the weekend, never failed to spike our adrenaline. On our last night, we even enjoyed a special visit from the neighborhood elephant. Tired from a long day, we had gathered at our campsite expecting only a mix of tents, tired safari goers, and a peaceful evening. Instead we found a crowd gathering near the fenced-in cooking stations. DebyeHckel theoryThe DebyeHckel theory was proposed by Peter Debye and Erich Hckel as a theoretical explanation for departures from ideality in solutions of electrolytes and plasmas.[1] It is a linearized PoissonBoltzmann model, which assumes an extremely simplified model of the electrolyte solution but nevertheless gave accurate predictions of mean activity coefficients for ions in dilute solution. The DebyeHckel equation provides a starting point for modern treatments of non-ideality of electrolyte solutions.[2]OverviewIn the chemistry of electrolyte solutions, an ideal solution is a solution whose colligative properties are proportional to the concentration of the solute. Real solutions show departures from this kind of ideality at all but the very lowest concentrations (see, for example, Raoult's law). In order to accommodate these effects in the thermodynamics of solutions, the concept of activity was introduced: the properties are then proportional to the activities of the ions. Activity, a, is proportional to concentration, c. The proportionality constant is known as an activity coefficient, .[3]

In an ideal electrolyte solution the activity coefficients of all the ions are equal to one. Non-ideality arises principally (but not exclusively) because ions of opposite charge attract each other due to electrostatic forces, while ions of the same charge repel each other. In consequence ions are not randomly distributed throughout the solution, as they would be in an ideal solution.Activity coefficients of single ions cannot be measured experimentally because an electrolyte solution must contain both positively charged ions and negatively charged ions. Instead, a mean activity coefficient, is defined. For example, with the electrolyte NaCl

In general, the mean activity coefficient of a fully dissociated electrolyte of formula AnBm is given by[4]

Activity coefficients are themselves functions of concentration as the amount of inter-ionic interaction increases as the concentration of the electrolyte increases. Debye and Hckel developed a theory with which single ion activity coefficients could be calculated. By calculating the mean activity coefficients from them the theory could be tested against experimental data. It was found to give excellent agreement for "dilute" solutions.The model

An idealized representation of a solution of a 1:1 electrolyteA description of DebyeHckel theory includes a very detailed discussion of the assumptions and their limitations as well as the mathematical development and applications.[5]A snapshot of a 2-dimensional section of an idealized electrolyte solution is shown in the adjacent picture. The ions are shown as spheres with unit electrical charge. The solvent (pale blue) is shown as a uniform medium, without structure. On average, each ion is surrounded more closely by ions of opposite charge than by ions of like charge. These concepts were developed into a quantitative theory involving ions of charge z1e+ and z2e, where z can be any integer. The principal assumption is that departure from ideality is due to electrostatic interactions between ions, mediated by Coulomb's law: the force of interaction between two electric charges, separated by a distance, r in a medium of relative permittivity r is given by[6]

It is also assumed that The solute is completely dissociated; it is a strong electrolyte. Ions are spherical and are not polarized by the surrounding electric field. Solvation of ions is ignored except insofar as it determines the effective sizes of the ions. The solvent plays no role other than providing a medium of constant relative permittivity (dielectric constant). There is no electrostriction. Individual ions surrounding a "central" ion can be represented by a statistically averaged cloud of continuous charge density, with a minimum distance of closest approach.The last assumption means that each cation is surrounded by a spherically symmetric cloud of other ions. The cloud has a net negative charge. Similarly each anion is surrounded by a cloud with net positive charge.