Light Colour Shade

Catching the fleeting scenes of many splendored life with a camera.
'Look closely. The beautiful may be small' — Kant

24 June 2015

The Common Starling (Sturnus vulgaris) and Wood Pigeon (Columba palumbus).

The common starling (Sturnus vulgaris), also known as the European starling, is a passerine bird in the starling family, Sturnidae. It is about 20 cm (8 in) long and has glossy black plumage, which is speckled with white at some times of year. The legs are pink and the bill is black in winter and yellow in summer. It is a noisy bird, especially in communal roosts and other gregarious situations, with a varied song that sometimes sounds like a wolf-whistle. Its gift for mimicry has been noted in literature including the Mabinogion and the works of Pliny the Elder and William Shakespeare (hmm, that would explain the wolf-whistling). Large flocks of this species can be beneficial to agriculture by controlling invertebrate pests; however, starlings can also be pests themselves when they feed on fruit and sprouting crops.

Common starling (Sturnus vulgaris) on a twig.  (by-nc-nd)

19 June 2015

Yellowhammer (Emberiza citrinella) Female

Yellowhammer (Emberiza citronella) female in a puddle. (by-nc-nd)

18 June 2015

Iris Pseudacorus (Yellow Flag, Yellow Iris, Water Flag) Flowers

Iris pseudacorus (yellow flag, yellow iris, water flag) is a species in the genus Iris, of the family Iridaceae. It is native to Europe, western Asia and northwest Africa. The rhizome has historically been used as an herbal remedy, but when applied to the skin or inhaled, the tannin-rich juices can be acrid and irritating. Not only is yellow iris a beautiful ornamental plant, but also a form of water treatment since it has the ability to take up heavy metals through its roots.

Iris pseudacorus (yellow flag, yellow iris, water flag) flower close-up. (© LightColourShade. All rights reserved)

25 May 2015

Rabbit suite. European rabbit or common rabbit (Oryctolagus cuniculus)

The European rabbit or common rabbit (Oryctolagus cuniculus) is native to south-western Europe (Spain and Portugal) and northwest Africa (Morocco and Algeria). The animal’s decline in its native range (caused by the diseases myxomatosis and rabbit calicivirus, as well as overhunting and habitat loss), has, in turn, caused the decline of its highly dependent predators, the Iberian lynx and the Spanish imperial eagle.”

European rabbit or common rabbit (Oryctolagus cuniculus) close-up. (© LightColourShade. All rights reserved)

4 March 2015

Schlumbergera Russeliana

Schlumbergera is a small genus of cacti (although they don’t really look like common cacti) with six species found in the coastal mountains of south-eastern Brazil. Plants grow on trees or rocks in habitats which are generally relatively cool, shady and of high humidity.

Schlumbergera russeliana flower. (© LightColourShade. All rights reserved) 

9 February 2015

Homing pigeon (Columba livia domestica), Common Blackbird (Turdus merula), Eurasian Common Moorhen (Gallinula chloropus), Common Wood Pigeon (Columba palumbus), Common Pochard (Aythya ferina), and Great Cormorant (Phalacrocorax carbo)

Homing pigeon is a variety of domestic pigeon (Columba livia domestica) derived from the rock pigeon, selectively bred to find its way home over extremely long distances (up to 1,800 km). The wild rock pigeon has an innate homing ability, meaning that it will generally return to its nest and mate. Their average flying speed over moderate distances is around 80 km/h (50 miles per hour) but speeds of up to 140 km/h (90 miles per hour) have been observed in top racers for short distances. Homing pigeons are called messenger or carrier pigeons when they are used to carry messages. Pigeons can find their way back from distant places they have never visited before. Most researchers believe that homing ability is based on a "map and compass" model, with the compass feature allowing birds to orient and the map feature allowing birds to determine their location relative to a goal site (home loft). While the compass mechanism appears to rely on the sun, some researchers believe that the map mechanism relies on the ability of birds to detect the Earth's magnetic field. Scientists discovered on top of pigeon's beak large number of particles of iron which remain aligned to north like manmade compass, thus it acts as compass which helps pigeon in determining its home, and it looks like the trigeminal nerve plays a role in magnetoception, too. Some studies showed that pigeons also orient themselves using the spatial distribution of atmospheric odours, known as olfactory navigation, as well as low frequency infrasound. In areas they have previously visited, pigeons are probably guided by visual landmarks, such as roads and other man-made features, just like humans. However, various experiments suggest that different breeds of homing pigeons rely on different cues to different extents.

Homing pigeon (Columba livia domestica) portrait. (© LightColourShade. All rights reserved)

21 December 2014

European Robin (Erithacus rubecula)

European robin (Erithacus rubecula), is a small insectivorous passerine bird -- a chat that is now considered to be an Old World flycatcher. It is found across Europe, east to Western Siberia and south to North Africa. British robins are usually resident but a few, usually females, migrate to southern Europe during winter as far as Spain, while Scandinavian and Russian robins migrate to Britain and western Europe. These migrants can be recognised by the greyer tone of the upper parts of their bodies and duller orange breast. In autumn and winter, robins add to their usual diet of terrestrial invertebrates, such as spiders, worms and insects, berries, fruits or seeds. Despite their cute look, male robins show highly aggressive territorial behaviour not only attacking other males that stray into their territories, but also other small birds without apparent provocation.

While humanity is generally bedazzled by space exploration perceived as pushing new boundaries, I believe this planet contains the most inextricable mysteries of the Universe (unless there are more planets like earth), the great bulk of which is still beyond our ken -- after all Universe is a dark cold and deadly empty place. This tiny bird is one of such marvels -- like many other birds robins have the ability to sense the magnetic field of the earth for navigation which is affected by the light entering the bird's eye.
The physical mechanism of the robin's magnetic sense is not fully understood, some scientists even throw in theories like quantum entanglement of electron spins. There exist two main hypotheses to explain the phenomenon of magnetoreception in animals. One hypotheses holds that, cryptochrome, when exposed to blue light, becomes activated to form a pair of two radicals (molecules with a single unpaired electron) where the spins of the two unpaired electrons are correlated. The surrounding magnetic field affects the kind of this correlation (parallel or anti-parallel), and this in turn affects the length of time cryptochrome stays in its activated state. Activation of cryptochrome (a class of blue light-sensitive flavoproteins found in plants and animals. Cryptochromes are involved in the circadian rhythms of plants and animals, and in the sensing of magnetic fields in a number of species) may affect the light-sensitivity of retinal neurons, with the overall result that the bird can "see" the magnetic field. The Earth's magnetic field is only 0.5 Gauss and so it is difficult to conceive of a mechanism by which such a field could lead to any chemical changes other than those affecting the weak magnetic fields between radical pairs. (Cryptochromes are thought to be essential for the light-dependent ability of the fruit fly Drosophila melanogaster to sense magnetic fields.) According to another model, Fe3O4, also referred to as iron (II, III) oxide or magnetite, a natural oxide with strong magnetism remains permanently magnetized when its length is larger than 50 nm and becomes magnetized when exposed to a magnetic field if its length is less than 50 nm. In both cases the Earth's magnetic field produces a transducible signal via a physical effect on this magnetically sensitive oxide.

European robin (Erithacus rubecula). (by-nc-nd)
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