''Glaucous'' (, ) is used to describe the pale grey or bluish-green appearance of the surfaces of some plants, as well as in the names of birds, such as the

glaucous gull The glaucous gull (''Larus hyperboreus'') is a large gull, the second-largest gull in the world. It breeds in Arctic regions of the Northern Hemisphere and winters south to shores of the Holarctic. The genus name is from Latin ''larus'', which a ...

(''Larus hyperboreus''),

glaucous-winged gull The glaucous-winged gull (''Larus glaucescens'') is a large, white-headed gull. The genus name is from Latin ''Larus'' which appears to have referred to a gull or other large seabird. The specific ''glaucescens'' is New Latin for " glaucous" fro ...

(''Larus glaucescens''), glaucous macaw (''Anodorhynchus glaucus''), and

glaucous tanager The glaucous tanager (''Thraupis glaucocolpa'') is a species of bird in the family Thraupidae. The term ''glaucous'' describes its colouration. It is found in Colombia and Venezuela. Its natural habitats are subtropical or tropical moist ...

(''Thraupis glaucocolpa''). The term ''glaucous'' is also used

botanical Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek wo ...

ly as an

adjective In linguistics, an adjective (list of glossing abbreviations, abbreviated ) is a word that generally grammatical modifier, modifies a noun or noun phrase or describes its referent. Its semantic role is to change information given by the noun. Tra ...

to mean "covered with a greyish, bluish, or whitish waxy coating or bloom that is easily rubbed off" (e.g. glaucous leaves). The first recorded use of ''glaucous'' as a color name in English was in the year 1671.

Examples

The

epicuticular wax Epicuticular wax is a coating of wax covering the outer surface of the plant cuticle in land plants. It may form a whitish film or bloom on leaves, fruits and other plant organs. Chemically, it consists of hydrophobic organic compounds, mainly str ...

coating on mature

plum A plum is a fruit of some species in ''Prunus'' subg. ''Prunus'.'' Dried plums are called prunes. History Plums may have been one of the first fruits domesticated by humans. Three of the most abundantly cultivated species are not found i ...

fruit gives them a glaucous appearance. Another familiar example is found in the common grape genus (''

Vitis vinifera ''Vitis vinifera'', the common grape vine, is a species of flowering plant, native to the Mediterranean region, Central Europe, and southwestern Asia, from Morocco and Portugal north to southern Germany and east to northern Iran. There are curre ...

''). Some

cacti A cactus (, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word ''cactus'' derives, through Latin, from the Ancient Greek ...

have a glaucous coating on their stem(s). Glaucous coatings are

hydrophobic In chemistry, hydrophobicity is the physical property of a molecule that is seemingly repelled from a mass of water (known as a hydrophobe). In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to be nonpolar and, th ...

so as to prevent

wetting Wetting is the ability of a liquid to maintain contact with a solid surface, resulting from intermolecular interactions when the two are brought together. This happens in presence of a gaseous phase or another liquid phase not miscible with th ...

by rain. Their waxy character serves to hinder climbing of leaves, stem or fruit by insects. On fruits, glaucous coatings may function as a deterrent to climbing and feeding by small insects in favor of increased seed dispersal offered by larger animals such as

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

s and birds. The blue-grey camouflage coloring of some species of birds and sea and land animals causes their appearance to blend with their surroundings, making their detection by predators or prey difficult. File:Close up grapes.jpg, Wine grapes with glaucous coating File:Plums.jpg, Plums with some glaucous coating visible File:Sedum_spathulifolium_4916.JPG, ''

Sedum spathulifolium ''Sedum spathulifolium'' is a species of flowering plant in the family Crassulaceae known by the common names broadleaf stonecrop, yellow stonecrop, and spoon-leaved stonecrop. An evergreen perennial, it is native to western North America from B ...

'' is a glaucous perennial

herbaceous plant Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of t ...

. File:Glaucous Gull (Larus hyperboreus) (13667579863).jpg, ''

Larus hyperboreus The glaucous gull (''Larus hyperboreus'') is a large gull, the second-largest gull in the world. It breeds in Arctic regions of the Northern Hemisphere and winters south to shores of the Holarctic. The genus name is from Latin ''larus'', which a ...

'' (glaucous gull) File:Blueshark 300.jpg,

Blue shark The blue shark (''Prionace glauca''), also known as the great blue shark, is a species of requiem shark, in the family Carcharhinidae, which inhabits deep waters in the world's temperate and tropical oceans. Averaging around and preferring co ...

(''Prionace glauca'')

References

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* Plant morphology Shades of gray Shades of blue Bird colours {{Shades of grey, US=yes, state=autocollapse

Examples

See also

References

External links