Native to Australia, White's Tree Frog grows up to 10 centimetres in length and is a popular household pet. In captivity, they have an average lifespan of 16 years. Its skin secretions contain caerins, a group of peptides with antibacterial and antiviral properties. Other peptides have been found to destroy HIV without harming healthy T-cells.
Coloured smoke reveals a vortex of air created by the wing of an airplane, also known as wake turbulence or jetwash. This turbulence can be especially hazardous during the landing and take off phases of flight, where an aircraft's proximity to the ground makes a timely recovery from turbulence-induced problems unlikely.
A wickiup is a domed hut-like dwelling used by the semi-nomadic Native American tribes of southwestern North America. A wigwam is a similar structure but the term is used for those found in the northeastern part of America. Shown here is an Apache wickiup from 1903.
The Nez Perce tribe lived in the northwestern United States, although they were known to head as far east as the Great Plains. They fought the last great battle between the U.S. government and an Indian nation as Chief Joseph and his warriors battled U.S. Cavalry troops over 1,600 miles (2,560 km) towards Canada before surrendering on October 5, 1877. This photograph was taken in 1910.
In botany, a leaf is an above-ground plantorgan specialized for photosynthesis. For this purpose, a leaf is typically flat (laminar) and thin, to expose the chloroplast containing cells (chlorenchyma tissue) to light over a broad area, and to allow light to penetrate fully into the tissues. This chart shows three aspects of leaf morphology: shape, margin (edge), and venation (arrangement of the veins).
A rooster or cock is a male chicken. The term "rooster" is reputedly so used because the cock is said to roost over clutches of eggs to guard them. In fact, "roosting" is the action of perching aloft to sleep at night, and is done by both sexes. Roosters often are pictured in art as crowing at the break of dawn, and this is accurate. However, they will also crow during the rest of the day, and even sometimes on a bright moonlit night.
The White-breasted Nuthatch (Sitta carolinensis) is a small songbird found in North America. The adult birds are about 155 mm (6 in.) long. They forage on the trunk and large branches of trees, often descending head first. Their principal diet consists of insects and a few varieties of seeds. They often travel with small mixed flocks in winter.
Schloss Neuschwanstein ("new swan stone castle") in southwest Bavaria is one of Germany's most popular tourist destinations. Construction was started by King Ludwig II and took 17 years. After his death in 1886, the castle was opened to the public. During World War II, many valuable items (all stolen) were stored at the castle, destined for Adolf Hitler's personal collection.
San Francisco International Airport (IATA: SFO) opened on May 7, 1927 on 150 acres (607,000 m²) of cow pasture leased from prominent local landowner Ogden L. Mills, and was named Mills Field Municipal Airport. During the economic boom of the 1990s and the dot com boom, SFO became the 6th busiest international airport in the world. However, since the boom times ended, it has fallen back out of the top twenty.
Vaduz/vaˈduːts/ is the capital of the principality of Liechtenstein. It is the seat of the national parliament. The town has about 5,000 inhabitants, most of whom are Roman Catholic, and is located along the Rhine. It is thought to have been founded in the 13th century by the Counts of Werdenberg. In 1322 there is mention of the castle which was sacked by the Swiss in 1499.
The International Space Station is located in a low Earth orbit, approximately 360 km (220 miles) high. The station has a capacity for a crew of three and there have always been at least two people on board. It has been visited by astronauts from a large number of countries and was also the destination of the first three space tourists.
Vatnajökull (IPA: [ˈvahtnajœːkʏtl ̥]), the largest glacier in Iceland, is located in the southeast and covers more than 8% of the country. The lakes on the glacier known as Grímsvötn, pictured here, are caused by volcanic eruptions which melt enough ice to fill the Grímsvötn caldera with water.
The Queen Elizabeth II Great Court of the British Museum is a covered square designed by the architects Foster and Partners. It opened in December 2000 and is the largest covered square in Europe. The roof is a glass and steel construction with 1,656 pairs of uniquely shaped glass panes. At the centre of the Great Court is the Reading Room, which is open to any member of the public who wishes to read there.
Cumulus clouds are characterized by dense individual elements in the form of puffs, mounds or towers, with flat bases and tops that often resemble cauliflower. They are formed due to convection. Buoyant, upward air currents, known as thermals rise to a height at which the moisture in the air can condense. Because of this, they "grow" vertically instead of horizontally. Though most common in warm, summer weather, cumulus clouds can be formed at any time of year.
On January 28, 1986, a ruptured O-ring in the right solid rocket booster caused the Space Shuttle Challenger to explode soon after launch. This photograph shows the main engines and solid rocket booster exhaust plumes entwined around a ball of gas from the external tank. Because shuttle launches had become almost routine after fifty successful missions, those watching the shuttle launch in person and on television found the sight of the break up especially shocking and difficult to believe until NASA confirmed the accident.
Lava tubes are natural conduits through which lava travels beneath the surface of a lava flow. They can be actively draining lava from a source, or can be extinct, meaning the lava flow has ceased and the rock has cooled and left a long, cave-like channel. Tubes form in one of two ways: by the crusting over of lava channels and from Pahoehoe flows where the lava is moving under the surface.
Cuttlefish are small relatives of squids and nautilus, sometimes called the chameleon of the sea because of their remarkable ability to rapidly alter their skin color at will. They have an internal shell, large eyes, and eight arms and two tentacles furnished with denticulated suckers, by means of which they secure their prey. There are 119 species of cuttlefish.
The bush is a term used for rural, undeveloped land or country areas in many places, such as Australia, New Zealand, Canada, South Africa, and Alaska. Because the geography varies greatly between these different places, what constitutes bush also widely differs. In Australia (as seen here), the term is quite specific: It can include agricultural areas and regional settlements, and does not include the even more remote areas that constitute the outback.
Sea anemones are water-dwelling, filter feeding animals, closely related to coral and jellyfish. They are composed of a small sac, attached to the bottom by an adhesive foot, with a column shaped body ending in an oral disc which contains the mouth, surrounded by the tentacles with stinging cells. The tentacles contain neurotoxins, which serve to paralyze and capture the prey, which is then moved by the tentacles to the mouth for digestion inside a central cavity. Anemones tend to stay in the same spot unless they are unhappy with that location, or a predator is attacking them. In the case of an attack, anemones can uproot themselves and swim away to a new location.
A rainbow is an optical and meteorological phenomenon that causes a nearly continuous spectrum of light to appear in the sky when the Sun shines onto droplets of moisture in the Earth's atmosphere. A rainbow does not actually exist at a location in the sky, but rather is an optical illusion whose apparent position depends on the observer's location. Even though a rainbow spans a continuous spectrum of colours, traditionally the full sequence of colours is most commonly cited as red, orange, yellow, green, blue, indigo, and violet. Indigo is usually included despite the poor ability of humans to distinguish colours in the blue portion of the visual spectrum.
Carbon nanotubes are cylindrical carbonmolecules with novel properties that make them potentially useful in a wide variety of applications. They exhibit extraordinary strength and unique electrical properties, and are efficient conductors of heat. Their name is derived from their size, since the diameter of a nanotube is on the order of a few nanometers (approximately 50,000 times smaller than the width of a human hair), while they can be up to several micrometers in length.