''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. The genus name is from Latin , which appears to have referred to a gull or other large seabird. The specific name is Latin for "northern" from the A ...

(''Larus hyperboreus''), glaucous-winged gull (''Larus glaucescens''),

glaucous macaw The glaucous macaw (''Anodorhynchus glaucus'') is a critically endangered or possibly extinct species of large, blue and grey South American parrot, a member of a large group of neotropical parrots known as macaws. This macaw is closely related ...

(''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 lowla ...

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

botanical Botany, also called plant science, is the branch of natural science and biology studying plants, especially Plant anatomy, their anatomy, Plant taxonomy, taxonomy, and Plant ecology, ecology. A botanist or plant scientist is a scientist who s ...

ly as an

adjective An adjective (abbreviations, abbreviated ) is a word that describes or defines a noun or noun phrase. Its semantic role is to change information given by the noun. Traditionally, adjectives are considered one of the main part of speech, parts of ...

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 waxy coating which covers 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 ...

coating on mature

plum A plum is a fruit of some species in Prunus subg. Prunus, ''Prunus'' subg. ''Prunus'.'' Dried plums are often called prunes, though in the United States they may be labeled as 'dried plums', especially during the 21st century. Plums are ...

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 Basin, Mediterranean region, Central Europe, and southwestern Asia, from Morocco and Portugal north to southern Germany and east to northern ...

''). Some

cacti A cactus (: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (), a family of the order Caryophyllales comprising about 127 genera with some 1,750 known species. The word ''cactus'' derives, through Latin, ...

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

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

so as to prevent

wetting Wetting is the ability of a liquid to displace gas to maintain contact with a solid surface, resulting from intermolecular interactions when the two are brought together. These interactions occur in the presence of either a gaseous phase or ...

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 A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

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,

Plum A plum is a fruit of some species in Prunus subg. Prunus, ''Prunus'' subg. ''Prunus'.'' Dried plums are often called prunes, though in the United States they may be labeled as 'dried plums', especially during the 21st century. Plums are ...

s 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 Br ...

'' 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 o ...

. File:Coquelicots - Parc floral 6.JPG, The glaucous leaves and seed pods of

Papaver somniferum ''Papaver somniferum'', commonly known as the opium poppy or breadseed poppy, is a species of flowering plant in the family Papaveraceae. It is the species of plant from which both opium and poppy seeds are derived and is also a valuable orname ...

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

Glaucous gull The glaucous gull (''Larus hyperboreus'') is a large gull, the second-largest gull in the world. The genus name is from Latin , which appears to have referred to a gull or other large seabird. The specific name is Latin for "northern" from the A ...

(''Larus hyperboreus'') 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 and the only member of its genus which inhabits deep waters in the world's temperate and tropical oceans. Ave ...

(''Prionace glauca'')

References

External links

* Plant morphology Shades of gray Shades of blue Bird colours {{Color-stub

Examples

See also

References

External links