Air-Tree

The Air-Tree is a single task artificial tree that focuses solely on the purification of our breathing air (I’m not sure what other tasks a tree has).

The Air-Tree is a creatively designed eco-machine that sucks in the bad air through a fan at the base of the structure and filters it up to the top to release cleaner, fresher air into the atmosphere.

The Air-Tree, like all other trees do, provides an area to sit for the tired pedestrian and, unlike all other trees, is equipped with LED to create an ambient mood around the beautiful edifice.

FLO2

Olivia Bradateanu, an industrial designer from Montclair, NJ, has created a concept air purifier design she calls the ‘FLO2.’ The air purifier uses photosynthesis, a natural process that plants use to convert water, and carbon dioxide to oxygen and sugar using light.

The leaf-shaped air purifier is small and movable. Its curved shape and inviting lines are evidence that it is designed to be touched.

Gravity Filtered Water

Made of porcelain, glass and metal, the Ovopur water dispenser from Aquaovo doesn’t use any electricity. It uses gravity to filter and revitalize tap water. The water dispenser has a reusable, multilayer, 100 percent recyclable filter cartridge which removes impurities from the water. It holds up to 11 liters of fresh water.

The Nosk nose filter

Hayfever sufferers go through misery when they breathe in allergens like dust, pollen and mold spores. They sneeze, cough and their eyes water. The Nosk nose filter now offers these individuals an alternative to pharmaceutical solutions.

Twin soft filters are inserted inside the nostrils with just a thin translucent plastic strip showing on the outside. It’s almost invisible and will suit those who don’t care if people think it might be snot! Having something up your nose might also take some getting used to if this is to work, however.

CO2 Scraper

The ‘CO2 Scraper’ by Nectar Product Development is a carbon-positive building that will actually purify the surrounding air cleaner. It’s meant for high-pollution areas like factories, but I could see several of these in global metropolitan areas noted for their pollution like Los Angeles and Beijing.

The ‘CO2 Scraper’ is a giant skyscraper that is essentially a vertical forest. It can hold 200-400 large trees, which naturally absorb carbon dioxide and convert it into oxygen. A windmill-powered irrigation system fertilizes and waters the trees; the only outside electricity Nectar Product Development says the ‘CO2 Scraper’ needs is for an elevator so that maintenance workers can ascend the tower

Windmill Filters Salt Water

It’s always great when we get to feature new inventions that could change the world for the better. Take this windmill for example. It’s capable of turning salt water into pure, clean drinking water.

There are so many countries in the world that, despite being surrounded by ocean, suffer a serious lack of drinking water. There is no electricity required for the reverse osmosis system, so it could be an ideal solution for many third world countries. It’s capable of producing enough water for 500 people in a single day. Water reservoirs will allow enough water to be stored for five days, so even in mild drought situations, or if there is not enough wind for a few days, there will be enough reserve water.

“The windmill was designed at the Delft University of Technology (TU Delft) in The Netherlands,” DailyTech.com explains. “It runs by using the wind’s mechanical force to pump water, and utilizes a high tech reverse osmosis membrane. The pumped water is pushed against this membrane at approximately 60 bar of pressure, and the salt is kept inside while pure water travels across the membrane.

“The windmill setup is estimated to 5 to 10 m3 of fresh water a day, based on the device’s capacity at varying wind speeds.”

This could be world changing. If these wind-driven machines were installed in nations in which people are being forced to drink contaminated drinking water, millions of diseases and deaths could be prevented.

Solar Container Purifies Water

This solar container was created by the Italian designers Alberto Medo and Francisco Gomez Paz. The water bottle’s design was inspired by needs of developing countries, specifically with the intentino of killing harmful microorganism that contaminate the water. Unfiltered water contributes to nearly 2.5 million deaths each year and can cause very vicious diseases.

The bottle uses SODIS (solar water disinfection), a technology developed at the Swiss Federal Institute of Water and Sanitation. When mixed into drinking water, SODIS works together with the sun’s UV-A radiation and increased temperature to kill the majority of the microorganisms. This new technology could literally be a life saver.

Minus A2 air purifier

You can customize your Minus A2 air purifier by choosing the customized filter that will benefit you most. You have a choice of pet, baby and new house. Each type of customized filter is specially engineered to trap and destroy different type of germs, chemicals or allergens. The unit also comes with six stages purifications and deodorizations. Traps airborne allergens and contaminants down to 0.3 microns in size, 99.97% of the time

China's Miyi Tower Will Clean River Below, Foster Cultural Arts Above

Los Angeles-based architects Studio SHIFT and SWA Group recently won a competition to revitalize New South Town in the Sichuan Provence of China. What you see here are the renderings for the Miyi Tower, an incredibly forward-thinking architectural design.

The above-ground portion of China’s Miyi Tower will be a community space, packed with amenities that, according to Inhabitat, will feature educational, entertainment and community programs specifically target towards promoting Chinese heritage and natural resources. There will be an auditorium, restaurants and exhibition spaces implemented throughout.

Beneath the community space portion of Miyi Tower, however, the magic really begins. State-of-the-art mechanical and natural filtration in the southern portion of the tower will filter the heavily-polluted Anning River and thereby transform it into a habitat to support a thriving ecosystem.

South Korea Oxygen Concentrators

List of "Oxygen Concentrators" for sale.

Website: http://www.alibaba.com/countrysearch/KR-suppliers/Oxygen_Concentrator.html

PLANTS FOR HEALTH: Fight Air Pollution With Plants!

It has been almost 20 years since the EPA confirmed the dangers of indoor VOCs (volatile organic chemicals), yet so little has been done to make the air inside our homes and offices and less toxic. Poor ventilation systems, sealed buildings and our use of synthetic products in the home are the main causes of our inner-pollution and, for most of us, these problems can’t be reversed overnight. But with the help of plant therapy, we can combat household VOCs and breathe easier. That is why we are super excited about this excellent Plants for Your Health chart from Good Magazine.

Good has made it easier to fight indoor air pollution by pairing pollutants with there botanical adversary in this quick reference chart for the home. Indoor air pollutants like gas heaters, smoke, pressed wood, insulation, paint, pets, humans and even air fresheners. All of which can have detrimental effects to your health including headaches, bronchitis, asthma, and skin irritations, just to name a few. Thankfully, a few potted plants here and there can reverse some of the toxic effects in your abode, and bring life and color to a beige on beige rental.
Chrysanthemums, spider plants, English ivy and weeping figs are among the dozens of plants that’ll do double duty in your home. Good Magazine’s super chart will guide you through your homes worst toxins and their botanical combatants.

Website: http://awesome.good.is/marketplace/010/010plants_for_health.html

Chloroplasmic Colonnade by Noah Baen

An environment created and nurtured by Brooklyn-based artist Noah Baen, “Chloroplasmic Colonnade” will be resident at Safe-T-Gallery in Dumbo from September 14 to October 14th. The installation will contain both living and inorganic elements, gathered mostly from the streets and back lots of Brooklyn, and will reflect on both our spiritual and our scientific understandings of the natural, green world.

Arranged a bit like a cloister, the different elements of the piece will be centered on a chloroplastic oxygen generator, a prop from a basic botany course, which will be actively capturing light energy and releasing pure oxygen -- oxygen that will be captured and periodically released into the gallery. Fully cognizant of the differences between the controlled, air-conditioned environment of an art gallery and the rougher, more immediate world of the streets of Brooklyn, the installation will attempt to broaden our understanding of each.

Website: http://www.safetgallery.com/NoahBaen/ChloroplasmicWriteup.html

Humanair Air Purifier Cleans Air Without Noise or Ozone Emissions

The United States Environmental Protection Agency has identified indoor air quality as one of the top five most urgent environmental risks to public health. Most currently available air cleaners are noisy and require filter replacement, while traditional electrostatic precipitator devices produce excessive ozone, a toxic gas that can harm the lungs. The Humanair can purify air without neither noise nor ozone emission. The device slowly moves high volumes of air in virtual silence with no noticeable draft.

Designed by Adrezej Loreth for Humanscale

Kamal Meattle on how to grow fresh air

Video: Kamal Meattle on how to grow fresh air | Video on TED.com

O Oxygen by Mathieu Lehanneur

In his ground-breaking new interiour design for Paris’ Flood Restaurants, visionary designer Mathieu Lehanneur has taken the integration of ecology and experiential design to new heights.

Sleek round aquariums sit throughout the space, each filled with 100-litres of Spirulina Plantesis. The micro algae creates oxygen through photosynthesis, aided by the large bright windows nearby. Besides their eye-popping futuristic vibe and awesome visual quality – the aquariums seem to almost glow with an organic phosphoresence – the pure, fresh oxygen they release into the air adds to a full-sensory, holistic experience. The design goes beyond what you can touch and see to improving the environment of the very atmosphere inside the space. You may not be able to consciously sense it, but undoubtedly your body will know.

Local River by Mathieu Lehanneur

Local River is a home storage unit for live freshwater fish combined with a mini vegetable patch. Local River is based on the principle of aquaponics coupled with the exchange and interdependence of two living organisms-plants and fish. The plants extract nutrients from the nitrate-rich fish waste. In doing so they act as a natural filter that purifies the water and maintains a vital balance for the eco-system in which the fish live.

Local River responds to everyday needs for 100% traceable fresh food and aims to replace the decorative ‘TV aquarium' by an equally decorative but also functional ‘refrigerator-aquarium'.

In collaboration with Anthony Van den Bossche

Andrea by Mathieu Lehanneur

Video Animation: YouTube - bel air lehanneur robillard

Designed by Mathieu Lehanneur and david edwards of harvard university, andrea is an air purifier which uses indoor plants to filter air. originally known as bel air, the design has gone through a number of tests in order to make it available to consumers with updated features. It is said that the air we breathe in the places where we live and work can often be 5 to 10 times more noxious than walking on the street, along with the dangerous chemicals found in commonly used household products.

Andrea is a response to counter our domestic pollution, by putting a green lung with enhanced capacities to filter the air and capture toxic particles into our homes. It enables the de-pollution of indoor air through the leaves and roots of the plant which is housed inside the unit. The best performing plants are those which are actually quite common, including spath or peace lily, red-edged dragon tree, spider plant and aloe vera.

Floating Garden By Duende

From Duende:

Floating Garden uses two techniques for eliminating nitrate wastes voided by fish:

1/ Gravel-bed filtration: tank water moves over a tray where it seeps thru a 5cm layer of river-sand. The sand bed traps suspended waste particles and forms a host environment for the aerobic and anaerobic bacteria that transform azote into nitrates.

2/ Aquaponics : nitrate-enriched water pours over a layer of plant-life. The substratum of roots extracts the nitrates to sustain plant growth, which means that water returning to the tank is pure. Needless to say, the vegetation is adapted to wet environments: e.g. Amazon-basin plants or tomatoes rather than cacti.

The combination of these two techniques in a simple easy-to-use product marketed for the general public as of spring 2010 is a significant innovation. It is a little known fact that aquarium fish are up front in the domestic pets market.
Aquarium water remains stable: it is clean and the tank needs only minimal upkeep: a sponge wipe over glass faces to remove algae deposits, an occasional top-up to compensate surface evaporation, and of course food for the fish.

The prototype on show for sale at Forum Diffusion as of 25 June was developed thanks to an Audi Talents Award that Benjamin Graindorge won early this year. It gives concrete form to a 'passion for waterworks' shared by Benjamin Graindorge and Duende Studio. What with Graindorge's 'Domestic landscapes' and the 'Local River' project developed with Mathieu Lehanneur by Anthony van den Bossche, it only needed one step more (and a lot of experiments) for the principle to be turned into a commercially-viable product, realistic but full of poetic potential. Elegant design associated to extended function make 'Floating Garden' an object rich in paradox - thoughtful and forward-looking.

List of Sensors

To find a comprehensive list of sensors, go to:

http://www.parallax.com/Store/Sensors/tabid/86/Default.aspx

Actuators

An actuator is a mechanical device for moving or controlling a mechanism or system. An actuator typically is a mechanical device that takes energy, usually transported by air, electric current, or liquid, and converts that into some kind of motion.

Actuators are devices designed to convert energy into motion. For different types of
actuators energy comes in different forms: mechanical, electrical and potential energy stored in compressed liquids or gasses.

Most commonly, actuators are used to achieve either linear or rotational motion and when connected to other components a wide range of applications can be covered. Click on this link to see some common applications actuators can be used for.

Based on the energy source, linear actuators are categorized primarily as electromechanical, mechanical, pneumatic and hydraulic.

Both pneumatic and hydraulic actuators utilize the pressure pushing against a piston to produce force and potion. In the case of hydraulic actuators pressure arises in the form of compressed liquid and in the case of pneumatic actuators in the form of gas.

Mechanical actuators convert one type of motion into another. In the case of linear
mechanical actuators rotational motion is converted into linear using a gears or screws. Electro-mechanical linear actuators utilize motors to produce rotational motion which is then converted into linear motion using screws, gears or other mechanical elements.

Dyson Air Technology

The Dyson Air Multiplier™ fan works very differently to conventional fans. It uses Air Multiplier™ technology to draw in air and amplify it 15 times, producing an uninterrupted stream of smooth air. With no blades or grill, it’s safe, easy to clean and doesn’t cause unpleasant buffeting.

Mahoney Tables

The Mahoney tables are a set of reference tables used in architecture, used as a guide to climate-appropriate design. They are named after architect Carl Mahoney, who worked on them together with John Martin Evans, and Otto Königsberger. They were first published in 1971 by the United Nations Department of Economic and Social Affairs.

The concept developed by Mahoney (1968) in Nigeria provided the basis of the
Mahoney Tables, later developed by Koenigsberger, Mahoney and Evans (1970), published by the United Nations in English, French and Spanish, with large sections included in the widely distributed publication by Koenigsberger et al. (1978). The Mahoney Tables (Evans, 1999; Evans, 2001) proposed a climate analysis sequence that starts with the basic and widely available monthly climatic data of temperature, humidity and rainfall, such as that found in HMSO (1958) and Pearce and Smith (1990), or data published by national meteorological services, for example SMN (1995). Today, the data for most major cities can be downloaded directly from the Internet (from sites such as http://www.wunderground.com/global/AG.html, 2006).

—John Martin Evans , The Comfort Triangles
The tables use readily-available climate data and simple calculations to give design guidelines, in a manner similar to a spreadsheet, as opposed to detailed thermal analysis or simulation. There are six tables; four are used for entering climatic data, for comparison with the requirements for thermal comfort; and two for reading off appropriate design criteria. A rough outline of the table usage is:

1.Air Temperatures. The max, min, and mean temperatures for each month are entered into this table.
2.Humidity, Precipitation, and Wind. The max, min, and mean figures for each month are entered into this table, and the conditions for each month classified into a humidity group.
3.Comparison of Comfort Conditions and Climate. The desired max/min temperatures are entered, and compared to the climatic values from table 1. A note is made if the conditions create heat stress or cold stress (i.e. the building will be too hot or cold).
4.Indicators (of humid or arid conditions). Rules are provided for combining the stress (table 3) and humidity groups (table 2) to check a box classifying the humidity and aridity for each month. For each of six possible indicators, the number of months where that indicator was checked are added up, giving a yearly total.
5.Schematic Design Recommendations. The yearly totals in table 4 correspond to rows in this table, listing schematic design recommendations, e.g. 'buildings oriented on east-west axis to reduce sun exposure', 'medium sized openings, 20%-40% of wall area'.
6.Design Development Recommendations. Again the yearly totals from table 4 are used to read off recommendations, eg 'roofs should be high-mass and well insulated'.

Website: http://en.wikipedia.org/wiki/Mahoney_tables

Psychrometrics

Psychrometrics or psychrometry are terms used to describe the field of engineering concerned with the determination of physical and thermodynamic properties of gas-vapor mixtures. The term derives from the Greek psuchron (ψυχρόν) meaning "cold" and metron (μέτρον) meaning "means of measurement".

Although the principles of psychrometry apply to any physical system consisting of gas-vapor mixtures, the most common system of interest is the mixture of water vapor and air, because of its application in heating, ventilating, and air-conditioning and meteorology. In human terms, our comfort is in large part a consequence of, not just the temperature of the surrounding air, but (because we cool ourselves via perspiration) the extent to which that air is saturated with water vapor.

Website: http://en.wikipedia.org/wiki/Psychrometrics

Human Thermal Comfort

Human thermal comfort is defined by ASHRAE as the state of mind that expresses satisfaction with the surrounding environment (ASHRAE Standard 55). Maintaining thermal comfort for occupants of buildings or other enclosures is one of the important goals of HVAC design engineers.

Thermal comfort is affected by heat conduction, convection, radiation, and evaporative heat loss. Thermal comfort is maintained when the heat generated by human metabolism is allowed to dissipate, thus maintaining thermal equilibrium with the surroundings. Any heat gain or loss beyond this generates a sensation of discomfort. It has been long recognised that the sensation of feeling hot or cold is not just dependent on air temperature alone.

Factors determining thermal comfort include:

Personal factors (health, psychology, sociology & situational factors)
Air temperature
Mean radiant temperature
Air movement/velocity (see wind chill factor)
Relative humidity (see also perspiration)
Insulative clothing
Activity levels.

Website: http://en.wikipedia.org/wiki/Thermal_comfort

Future Smart ‘Living’ Architecture

One of the most effective ways to cut down the ecological footprint of buildings is to follow the lead of nature through biomimicry. Habitat 2020 is a future forward example of biomimetic architecture that fuses high-tech ideas with basic cellular functions to create ‘living’ structures that operate like natural organisms. This nature-inspired approach to city living looks at the urban landscape as a dynamic and ever-evolving ecosystem. Within this cityscape, buildings open, close, breathe and adapt according to their environment.

The surface would allow the entry of light, air and water into the housing. It would automatically position itself according to the sunlight and let in light; thus electricity for lighting would not be needed during the day. The air and wind would be channeled into the building and filtered to provide clean air and natural air-conditioning. The active skin would be capable of rain water harvesting where water would be purified, filtered, used and recycled. The skin could even absorb moisture from the air. The waste produced would be converted into biogas energy that could be put to diverse uses in the habitat.

Website: http://www.ecofriend.org/entry/habitat-2020-the-green-architecture-of-the-future/

http://live.philips.com/index.php/nl_nl/video/off-the-grid-habitat-2020-vision/16713202001

Nine Basic Laws of Nature

01) Nature runs on sunlight
02) Nature uses only the energy it needs
03) Nuture fits form to function
04) Nature recycles everything
05) Nature rewards co-operation
06) Nature banks on diversity
07) Nature demands locall expertise
08) Nature curbs excesses from within
09) Nature taps the power of limits

- Janine Beyus

Lotus Leaf

The Lotus effect refers to the very high water repellency (superhydrophobicity) exhibited by the leaves of the lotus flower (Nelumbo).[1] Dirt particles are picked up by water droplets due to a complex micro- and nanoscopic architecture of the surface which enables minimization of adhesion.

Tardigrades

Tardigrades have found to be able to dry out completely but stay alive for months and months then regenerate itself.

Spider Silk

Spider silk is five times stronger than steel, ounce to ounce. It can elongate 40 per cent (unlike steel) and spring back to the original length, when released of load.

Abalone

The inner shell of a sea creature called 'abalone' is twice as tough as our highest tech ceramics. The nearest tougher material made by man is polyaramid Kevlar - a fibre so tough that it can stop bullets. But to make Kevlar, petroleum molecules are poured into a pressurised vat of concentrated sulphuric acid and boiled at several 1 00 of, in order to force it into a liquid crystal form. Then, it is subjected to high pressure drawing. The energy input is extreme, and this process results in toxic byproducts

Trees and Bones

Learning from Trees and Bones How to Optimize Strength and Materials
The next time you drive through a forest, go ahead and thank the trees out your window for helping on your car's crash safety and gas mileage. Trees engineer themselves in a number of ways to maximize their strength, such as arranging their fibers to minimize stress and adding material where strength is needed (take a look at the extra material beneath a heavy branch, for instance). Bones – unlike trees in that they must carry moving loads – go a step further by removing material where it's not needed, optimizing their structure for their dynamic workloads. Engineers have incorporated these and other lessons learned from how trees and bones optimize their strength and minimize their use of materials into software design programs, such as Claus Matteck's “Soft Kill Option” software, which are revolutionizing industrial design. Using these programs to design cars, for example, has resulted in new vehicle designs that are as crash-safe as conventional cars, yet up to 30% lighter.

Mussels

a sea-creature produces 'adhesive; uses it and cures it in 3 min, right inside water, to stick itself to anything in the tidal zone for eating or mating. This adhesive needs no primer and such a sticking power is unachieved by man-made adhesives. We are only dreaming of inventing one, which can work in moist conditions.

Rhino Horn

Rhino horn manages to self repair itself, through it contains no living cell.

Rhinoceros horns, unlike those of other horned mammals, consist of keratin only and lack a bony core, such as bovine horns. Rhinoceros horns are used in traditional Asian medicine.

Beetle-inspired Water Harvester

A fog-catching device patterned on the Namibian Beetle’s prodigious water harvesting abilities captures ten times more water than existing fog catching nets. The beetle’s ability to pull water from fog is due to bumps on its wing scales that have water-loving tips and water-shedding sides. QinetiQ (UK) has developed plastic water-harvesting sheets that mimic the beetle’s bumps, useful for capturing water in cooling towers and industrial condensers, arid agricultural systems, and buildings in fog-rich areas.

Website: http://news.nationalgeographic.com/news/2001/11/1101_TVdesertbeetle.html

Giant, Deep Sea Sponges Evolved Fiber Optic Exoskeletons

This gigantic sea sponge has an exoskeleton made of glass rods, and each rod can grow up to a meter in length. In the deep sea, these massive sponges contain a menagerie of other tiny lifeforms, all dependent on their sea sponge hosts for something in short supply far under the water. They need light - and some sponges have a evolved a way to provide it using fiber optics.

Sea sponges are among the most primitive animals on Earth. They don't move and don't have differentiated body structures. They basically have organized groups of cells living in an exoskeletal framework. Glass sponges build their exoskeletons from silica and create elaborate shapes from glass-like rods called spicules, pictured below.Some glass sponges get incredibly large, with spicules a meter long and surprisingly wide. No one was really sure why the sponges and their spicules sometimes grew so large. It turns out another mystery about sea sponges was the key to solving this one. The sponges often have millions of tiny organisms living inside them, like glass shrimp and algae. Those organisms need light to survive, and if you were writing a Lovecraftian horror story, there are worse analogies you could use than, "Dark as the inside of a sea sponge."

Some curious German scientists stuck photosensitive paper inside glass sponges, then shined a light into their spicules. Sure enough, the paper showed light exposure patterns consistent with the spicule positions. Those glass-like tubes are more glass-like than we thought. The sponges use them to transmit light (a rare commodity deep beneath the ocean) down into their own bodies, where it shines (dimly) onto their wee symbiotes. The spicules act exactly like fiber optic cables, even bending the light around curves. They're still waiting for FiOS though.

Website: http://io9.com/5085064/giant-deep-sea-sponges-evolved-fiber-optic-exoskeletons

Brittle Star Found Covered With Optically Advanced "Eyes"

Scientists have discovered a species of brittle star whose outer skeleton is covered with crystalline lenses that appear to work collectively as an all-seeing eye.

The visual system of lenses in the species Ophiocoma wendtii is the first of its kind observed in nature and is superior to any manufactured lenses, said Joanna Aizenberg, a researcher at Bell Laboratories in Murray Hill, New Jersey.

"These lenses have exceptional optical performance," said Aizenberg, who is co-author of a report on the discovery published in the August 23 issue of Nature. "They are compensated for physical effects that bother us when we fabricate lenses in the laboratory"—effects known as birefringence and spherical aberration.

Brittle stars are sea creatures that have long, thin arms emanating from a small disk-shaped body. They belong to the phylum of echinoderms, which includes sea urchins, sea cucumbers, and sea stars.

O. wendtii is about the size of an outstretched human hand and lives in coral reefs from Bermuda to Brazil.

Light Sensitive

Gordon Hendler, a marine biologist at the Natural History Museum of Los Angeles County in Los Angeles, California, and co-author of the study, discovered that O. wendtii is sensitive to light and can change color.

"They are dark reddish in color during the daytime and go through a striking change in color at night, turning a blackish brown and gray," he said.

After several years of studying the species, Hendler realized that the change in color is controlled by chromatophores, or cells that contain pigment. The chromatophores are clustered around clear "windows" in the bones on a brittle star's arms.

"I started thinking then that those windows might be involved in the reception of light by brittle stars," he said. "The chromatophores could control the amount of light let in."

Website: http://news.nationalgeographic.com/news/2001/08/0822_starfisheyes.html

Peacock - Colour Without Pigments

A peacock creates colour with shape. Light comes through, it bounces off the layers, its called thin film interference.

The male (peacock) Indian Peafowl has iridescent blue-green or green coloured plumage. The so-called "tail" of the peacock, also termed the "train," is not the tail quill feathers but highly elongated upper tail coverts. The train feathers have a series of eyes that are best seen when the tail is fanned. Both species have a crest atop the head.

The female (peahen) Indian Peafowl has a mixture of dull green, brown, and grey in her plumage. She lacks the long upper tail coverts of the male but has a crest. The female can also display her plumage to ward off female competition or danger to her young.

The Green Peafowl is different in appearance from the Indian Peafowl. The male has green and gold plumage and has an erect crest. The wings are black with a sheen of blue.

Unlike the Indian Peafowl, the Green Peahen is very similar to the male, only having shorter upper tail coverts and less iridescence. It is very hard to tell a juvenile male from an adult female.

Many of the brilliant colours of the peacock plumage are due to an optical interference phenomenon, Bragg reflection, based on (nearly) periodic nanostructures found in the barbules (fiber-like components) of the feathers.

Different colours correspond to different length scales of the periodic structures. For brown feathers, a mixture of red and blue is required: one colour is created by the periodic structure, and the other is a created by a Fabry-Perot interference peak from reflections off the outermost and innermost boundaries of the periodic structure.

Such interference-based structural colour is especially important in producing the peacock's iridescent hues (which shimmer and change with viewing angle), since interference effects depend upon the angle of light, unlike chemical pigments.

Website: http://en.wikipedia.org/wiki/Peafowl